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Laborists, Defined
Last month (see “Hospital-Focused Practice,” Septem-ber 2011, p. 61), I discussed the adoption of the hospitalist model of practice by many specialties, some of the common issues they face, and highlighted a national meeting to examine this phenomenon (for more information on the meeting, visit www.hospitalmedicine/hfpm). This month, relying mostly on my own experience with this practice model, I’ll drill deeper into OB hospitalists (also known as laborists). While there are a lot of ways in which hospitalist practice in many specialties are the same, laborists differ from those in other fields in important and interesting ways.
Prevalence
One of the most informative sources about the “laborist movement” is ObGynHospitalist.com, a website started and managed by Dr. Rob Olson, an enterprising laborist in Bellingham, Wash. As of July, the site listed 132 laborist programs nationwide (and that figure likely underestimates the actual number in operation). A survey of registered users of the website in April yielded 106 responses, representing a 24% response rate. Seventy-five of the respondents indicated they were full-time laborists.
Unique Drivers
Because obstetric malpractice costs are so high, and many lawsuits are related to delayed response to obstetric emergencies, there is hope (not much hard proof yet) that outcomes will be better, and lawsuits less common or less costly.1 So the hope of reduced malpractice costs figures more prominently into the cost-benefit analysis of the OB hospitalist model than most other types of HM practice.
Financial Model
It appears that all hospitalist models require financial support over and above professional fee revenue. Hospitals usually are willing (happy?) to provide this money because they can make back even more as a result of increased patient volume/market share or lower costs. And, as is the case for hospitalists in other specialties, laborist presence can be an asset in recruitment and retention of other OBGYNs.
I think the most interesting feature of laborist practice is that in many settings, it has the potential to open new sources of revenue—both hospital “facility fee” and professional fee revenue. A common practice in many hospitals is for obstetricians to send patients, or for them to self-present, to labor and delivery to be checked for a cold, vomiting, or whether labor has started. Many times, a nurse performs these checks, communicates with a doctor, then discharges the patient—and no bill is generated. An on-site laborist can see the same patients (presumably making for a higher-quality visit for the patient) and, assuming the visit is medically necessary, both a facility and professional charge can be submitted. Revenue from such visits can go a long way toward making up the difference between the total cost of the laborist program and fee collections. This adds to patient safety, as each patient is evaluated in person by a physician rather than only a nurse.
In most settings, the laborist submits a charge for delivery only for unassigned patients. For those patients who “belong to” another OB who provided prenatal care, it is often most practical for that doctor to submit the global fee for prenatal care and delivery, and to pay the laborist program an agreed-upon rate for each service provided.
Compensation
Laborists often are paid an hourly rate, and they typically don’t have a salary component tied to work relative-value unit (wRVU) production or other productivity metrics. Total annual compensation is typically lower than private-practice OBGYN physicians. It also varies widely, depending on local market forces, job description, and workload. Most programs are trying to implement meaningful quality bonuses for laborists.
Scope of Practice
Laborists typically provide care to all unassigned patients who present to labor and delivery, and perform deliveries, C-sections, and other services on patients when requested by OBs in traditional practice. Requests arise when an OB simply needs to be relieved of being on call for their private patients, or when an emergency arises. (These “as-needed” referrals are different from the most common arrangement for “medical hospitalist” practices that ask other doctors to refer all or none of their patients, not just when they are otherwise occupied.)
Lastly, the laborist might serve as surgical assistant to other OBGYNs. In nearly all settings, there is no need to require that any physicians refer to the laborist, and the other OBs are free to decide when to refer.
A reasonably common scenario is that, to avoid disruption of scheduled office hours, an OB in traditional practice might ask that the laborist manage a patient who presents in labor. But if still undelivered at the close of office hours, the traditional OB might assume care from that point on or have the laborist remain responsible through delivery. The traditional OB usually will make post-partum “rounding” visits on all of their patients but could rely on the laborist for these visits.
In most cases, the laborist does not have any scheduled gynecologic procedures, though he or she may see GYN consults throughout the hospital as time permits. Laborists typically have no outpatient responsibilities, but some OBGYN hospitalists cover GYN in the ED.
Operational Structure
Although models vary significantly, the single most common arrangement is for laborists to work 24-hour, in-house shifts. Rarely is there a need or justification to have more than one laborist on at a time. For a single physician, seven or eight 24-hour shifts per month is considered full-time. My experience is that most laborists are employed by the hospital in which they work.
As is the case in every specialty, some large OBGYN groups adopt a rotating laborist model, in which one member of their group becomes the laborist for 24 hours at a time, during which they are relieved of all other responsibilities.
Recruitment
ObGynHospitalist.com shows that, as of July, 40 of the 132 laborist programs that had identified themselves on the site were recruiting. My experience is that unlike “medical hospitalist” practices, which tend to successfully recruit those very early in their career, or “surgical hospitalist” programs, which target mid- to late-career general surgeons, laborist candidates come from any point in their careers. Most programs prefer that a laborist has several years of post-residency experience, but they generally have no other preference.
Dr. Nelson has been a practicing hospitalist since 1988 and is cofounder and past president of SHM. He is a principal in Nelson Flores Hospital Medicine Consultants, a national hospitalist practice management consulting firm (www.nelsonflores.com). He is course codirector and faculty for SHM’s “Best Practices in Managing a Hospital Medicine Program” course. This column represents his views and is not intended to reflect an official position of SHM.
Reference
Last month (see “Hospital-Focused Practice,” Septem-ber 2011, p. 61), I discussed the adoption of the hospitalist model of practice by many specialties, some of the common issues they face, and highlighted a national meeting to examine this phenomenon (for more information on the meeting, visit www.hospitalmedicine/hfpm). This month, relying mostly on my own experience with this practice model, I’ll drill deeper into OB hospitalists (also known as laborists). While there are a lot of ways in which hospitalist practice in many specialties are the same, laborists differ from those in other fields in important and interesting ways.
Prevalence
One of the most informative sources about the “laborist movement” is ObGynHospitalist.com, a website started and managed by Dr. Rob Olson, an enterprising laborist in Bellingham, Wash. As of July, the site listed 132 laborist programs nationwide (and that figure likely underestimates the actual number in operation). A survey of registered users of the website in April yielded 106 responses, representing a 24% response rate. Seventy-five of the respondents indicated they were full-time laborists.
Unique Drivers
Because obstetric malpractice costs are so high, and many lawsuits are related to delayed response to obstetric emergencies, there is hope (not much hard proof yet) that outcomes will be better, and lawsuits less common or less costly.1 So the hope of reduced malpractice costs figures more prominently into the cost-benefit analysis of the OB hospitalist model than most other types of HM practice.
Financial Model
It appears that all hospitalist models require financial support over and above professional fee revenue. Hospitals usually are willing (happy?) to provide this money because they can make back even more as a result of increased patient volume/market share or lower costs. And, as is the case for hospitalists in other specialties, laborist presence can be an asset in recruitment and retention of other OBGYNs.
I think the most interesting feature of laborist practice is that in many settings, it has the potential to open new sources of revenue—both hospital “facility fee” and professional fee revenue. A common practice in many hospitals is for obstetricians to send patients, or for them to self-present, to labor and delivery to be checked for a cold, vomiting, or whether labor has started. Many times, a nurse performs these checks, communicates with a doctor, then discharges the patient—and no bill is generated. An on-site laborist can see the same patients (presumably making for a higher-quality visit for the patient) and, assuming the visit is medically necessary, both a facility and professional charge can be submitted. Revenue from such visits can go a long way toward making up the difference between the total cost of the laborist program and fee collections. This adds to patient safety, as each patient is evaluated in person by a physician rather than only a nurse.
In most settings, the laborist submits a charge for delivery only for unassigned patients. For those patients who “belong to” another OB who provided prenatal care, it is often most practical for that doctor to submit the global fee for prenatal care and delivery, and to pay the laborist program an agreed-upon rate for each service provided.
Compensation
Laborists often are paid an hourly rate, and they typically don’t have a salary component tied to work relative-value unit (wRVU) production or other productivity metrics. Total annual compensation is typically lower than private-practice OBGYN physicians. It also varies widely, depending on local market forces, job description, and workload. Most programs are trying to implement meaningful quality bonuses for laborists.
Scope of Practice
Laborists typically provide care to all unassigned patients who present to labor and delivery, and perform deliveries, C-sections, and other services on patients when requested by OBs in traditional practice. Requests arise when an OB simply needs to be relieved of being on call for their private patients, or when an emergency arises. (These “as-needed” referrals are different from the most common arrangement for “medical hospitalist” practices that ask other doctors to refer all or none of their patients, not just when they are otherwise occupied.)
Lastly, the laborist might serve as surgical assistant to other OBGYNs. In nearly all settings, there is no need to require that any physicians refer to the laborist, and the other OBs are free to decide when to refer.
A reasonably common scenario is that, to avoid disruption of scheduled office hours, an OB in traditional practice might ask that the laborist manage a patient who presents in labor. But if still undelivered at the close of office hours, the traditional OB might assume care from that point on or have the laborist remain responsible through delivery. The traditional OB usually will make post-partum “rounding” visits on all of their patients but could rely on the laborist for these visits.
In most cases, the laborist does not have any scheduled gynecologic procedures, though he or she may see GYN consults throughout the hospital as time permits. Laborists typically have no outpatient responsibilities, but some OBGYN hospitalists cover GYN in the ED.
Operational Structure
Although models vary significantly, the single most common arrangement is for laborists to work 24-hour, in-house shifts. Rarely is there a need or justification to have more than one laborist on at a time. For a single physician, seven or eight 24-hour shifts per month is considered full-time. My experience is that most laborists are employed by the hospital in which they work.
As is the case in every specialty, some large OBGYN groups adopt a rotating laborist model, in which one member of their group becomes the laborist for 24 hours at a time, during which they are relieved of all other responsibilities.
Recruitment
ObGynHospitalist.com shows that, as of July, 40 of the 132 laborist programs that had identified themselves on the site were recruiting. My experience is that unlike “medical hospitalist” practices, which tend to successfully recruit those very early in their career, or “surgical hospitalist” programs, which target mid- to late-career general surgeons, laborist candidates come from any point in their careers. Most programs prefer that a laborist has several years of post-residency experience, but they generally have no other preference.
Dr. Nelson has been a practicing hospitalist since 1988 and is cofounder and past president of SHM. He is a principal in Nelson Flores Hospital Medicine Consultants, a national hospitalist practice management consulting firm (www.nelsonflores.com). He is course codirector and faculty for SHM’s “Best Practices in Managing a Hospital Medicine Program” course. This column represents his views and is not intended to reflect an official position of SHM.
Reference
Last month (see “Hospital-Focused Practice,” Septem-ber 2011, p. 61), I discussed the adoption of the hospitalist model of practice by many specialties, some of the common issues they face, and highlighted a national meeting to examine this phenomenon (for more information on the meeting, visit www.hospitalmedicine/hfpm). This month, relying mostly on my own experience with this practice model, I’ll drill deeper into OB hospitalists (also known as laborists). While there are a lot of ways in which hospitalist practice in many specialties are the same, laborists differ from those in other fields in important and interesting ways.
Prevalence
One of the most informative sources about the “laborist movement” is ObGynHospitalist.com, a website started and managed by Dr. Rob Olson, an enterprising laborist in Bellingham, Wash. As of July, the site listed 132 laborist programs nationwide (and that figure likely underestimates the actual number in operation). A survey of registered users of the website in April yielded 106 responses, representing a 24% response rate. Seventy-five of the respondents indicated they were full-time laborists.
Unique Drivers
Because obstetric malpractice costs are so high, and many lawsuits are related to delayed response to obstetric emergencies, there is hope (not much hard proof yet) that outcomes will be better, and lawsuits less common or less costly.1 So the hope of reduced malpractice costs figures more prominently into the cost-benefit analysis of the OB hospitalist model than most other types of HM practice.
Financial Model
It appears that all hospitalist models require financial support over and above professional fee revenue. Hospitals usually are willing (happy?) to provide this money because they can make back even more as a result of increased patient volume/market share or lower costs. And, as is the case for hospitalists in other specialties, laborist presence can be an asset in recruitment and retention of other OBGYNs.
I think the most interesting feature of laborist practice is that in many settings, it has the potential to open new sources of revenue—both hospital “facility fee” and professional fee revenue. A common practice in many hospitals is for obstetricians to send patients, or for them to self-present, to labor and delivery to be checked for a cold, vomiting, or whether labor has started. Many times, a nurse performs these checks, communicates with a doctor, then discharges the patient—and no bill is generated. An on-site laborist can see the same patients (presumably making for a higher-quality visit for the patient) and, assuming the visit is medically necessary, both a facility and professional charge can be submitted. Revenue from such visits can go a long way toward making up the difference between the total cost of the laborist program and fee collections. This adds to patient safety, as each patient is evaluated in person by a physician rather than only a nurse.
In most settings, the laborist submits a charge for delivery only for unassigned patients. For those patients who “belong to” another OB who provided prenatal care, it is often most practical for that doctor to submit the global fee for prenatal care and delivery, and to pay the laborist program an agreed-upon rate for each service provided.
Compensation
Laborists often are paid an hourly rate, and they typically don’t have a salary component tied to work relative-value unit (wRVU) production or other productivity metrics. Total annual compensation is typically lower than private-practice OBGYN physicians. It also varies widely, depending on local market forces, job description, and workload. Most programs are trying to implement meaningful quality bonuses for laborists.
Scope of Practice
Laborists typically provide care to all unassigned patients who present to labor and delivery, and perform deliveries, C-sections, and other services on patients when requested by OBs in traditional practice. Requests arise when an OB simply needs to be relieved of being on call for their private patients, or when an emergency arises. (These “as-needed” referrals are different from the most common arrangement for “medical hospitalist” practices that ask other doctors to refer all or none of their patients, not just when they are otherwise occupied.)
Lastly, the laborist might serve as surgical assistant to other OBGYNs. In nearly all settings, there is no need to require that any physicians refer to the laborist, and the other OBs are free to decide when to refer.
A reasonably common scenario is that, to avoid disruption of scheduled office hours, an OB in traditional practice might ask that the laborist manage a patient who presents in labor. But if still undelivered at the close of office hours, the traditional OB might assume care from that point on or have the laborist remain responsible through delivery. The traditional OB usually will make post-partum “rounding” visits on all of their patients but could rely on the laborist for these visits.
In most cases, the laborist does not have any scheduled gynecologic procedures, though he or she may see GYN consults throughout the hospital as time permits. Laborists typically have no outpatient responsibilities, but some OBGYN hospitalists cover GYN in the ED.
Operational Structure
Although models vary significantly, the single most common arrangement is for laborists to work 24-hour, in-house shifts. Rarely is there a need or justification to have more than one laborist on at a time. For a single physician, seven or eight 24-hour shifts per month is considered full-time. My experience is that most laborists are employed by the hospital in which they work.
As is the case in every specialty, some large OBGYN groups adopt a rotating laborist model, in which one member of their group becomes the laborist for 24 hours at a time, during which they are relieved of all other responsibilities.
Recruitment
ObGynHospitalist.com shows that, as of July, 40 of the 132 laborist programs that had identified themselves on the site were recruiting. My experience is that unlike “medical hospitalist” practices, which tend to successfully recruit those very early in their career, or “surgical hospitalist” programs, which target mid- to late-career general surgeons, laborist candidates come from any point in their careers. Most programs prefer that a laborist has several years of post-residency experience, but they generally have no other preference.
Dr. Nelson has been a practicing hospitalist since 1988 and is cofounder and past president of SHM. He is a principal in Nelson Flores Hospital Medicine Consultants, a national hospitalist practice management consulting firm (www.nelsonflores.com). He is course codirector and faculty for SHM’s “Best Practices in Managing a Hospital Medicine Program” course. This column represents his views and is not intended to reflect an official position of SHM.
Reference
Dr. Hospitalist
I was hoping someone would address Interqual criteria for admission. I have a pretty good knowledge about this and apply it to justify “intensity of service.” It seems that most ED docs don’t understand these criteria and, as a result, we end up having “too many obs,” per our CEO. What do I do? How do I get everyone on board the “hospitalist agenda wagon”?
I.U., Texas
Dr. Hospitalist responds: Many hospitals now use either Interqual or Milliman to help them make determinations as to whether a patient should be inpatient or observation. Regardless of the resource used, there should be some basic understanding as to what determines the admission status—namely, the “intensity of service,” as you describe.
First things first: I would not let the ED doc determine the admission status. The ED physician should continue to occupy their binary decision algorithm of 1) home and 2) admission. Once they decide on admission, they should make no further decisions regarding the care of the patient. Why? Well, they don’t work upstairs (or down the hall), and they generally have a poorer understanding than you do about admission status and the most appropriate unit for your patient.
Nationally, ED physicians (through American College of Emergency Physicians policy statements) have adopted the approach of no longer writing “admission” orders, instead calling them “transition” orders. I would do nothing to discourage this approach, even though it does make more work for us as hospitalists. So, as a starting point, you and your team should determine the admission location and the status. It might require a change in workflow, but it will save you headaches in the long run. When it comes to admission status, things get a little trickier. Evaluation of the admission status includes “severity of illness” and “intensity of service.” Clearly, you have more to do with the determination of the latter than the former (at least we hope so), and that is where you will interact with the hospital’s utilization review service. Let’s focus on that for the time being.
Roughly, observation should be used for patients for whom stabilization and discharge are expected within 24 hours, the patient is hemodynamically stable, and the clinical diagnosis is unclear. It used to be that “obs”—or observation—was only used for 23 hours, but Medicare now allows up to 48 hours of observation. CMS has a list of initial diagnoses that they view as appropriate for obs, such as chest pain, CHF, and syncope.
On the inpatient side, here it is straight from CMS: “Inpatient care, rather than outpatient care, is required only if the beneficiary’s medical condition, safety, or health would be significantly and directly threatened if care was provided in a less intensive setting. Without accompanying medical conditions, factors that would only cause the beneficiary inconvenience in terms of time and money needed to care for the beneficiary at home or for travel to a physician’s office, or that may cause the beneficiary to worry, do not justify a continued hospital stay.” (You can read more by downloading this PDF: www.cms.gov/MLNMatters Articles/Downloads/SE1037.pdf.)
Beware, though: This is a bit like going down the rabbit hole—you can get lost in all the regulations and amendments. Which, to no one’s great surprise, explains why Milliman and Interqual operate such big businesses interpreting and applying these guidelines. We all know that you can’t control the phone calls coming from the ED. However, it is paramount that when you accept a patient, you document clearly and appropriately the admission status and the clinical criteria used to make your determination. Will everyone get it right every time? Probably not. Remember, though, that documentation will not only support the admission status, but also your professional fee billing.
Now what? Educate, educate, educate.
Ideally, you should meet with your case management/UR team and decide how to deliver the message to your group. Honestly, I think that a group responds better to explanations coming from one of their own rather than inviting the head of case management to come and speak for an hour. Rather than risk setting up an adversarial relationship with case management, consider filtering the message through your leadership. As a group leader, you need to be able to interpret hospital-driven directives and deliver the information to your group in a constructive manner. As working hospitalists, we need to understand the nonclinical factors that affect us—and our hospitals. It’s part of the job.
I was hoping someone would address Interqual criteria for admission. I have a pretty good knowledge about this and apply it to justify “intensity of service.” It seems that most ED docs don’t understand these criteria and, as a result, we end up having “too many obs,” per our CEO. What do I do? How do I get everyone on board the “hospitalist agenda wagon”?
I.U., Texas
Dr. Hospitalist responds: Many hospitals now use either Interqual or Milliman to help them make determinations as to whether a patient should be inpatient or observation. Regardless of the resource used, there should be some basic understanding as to what determines the admission status—namely, the “intensity of service,” as you describe.
First things first: I would not let the ED doc determine the admission status. The ED physician should continue to occupy their binary decision algorithm of 1) home and 2) admission. Once they decide on admission, they should make no further decisions regarding the care of the patient. Why? Well, they don’t work upstairs (or down the hall), and they generally have a poorer understanding than you do about admission status and the most appropriate unit for your patient.
Nationally, ED physicians (through American College of Emergency Physicians policy statements) have adopted the approach of no longer writing “admission” orders, instead calling them “transition” orders. I would do nothing to discourage this approach, even though it does make more work for us as hospitalists. So, as a starting point, you and your team should determine the admission location and the status. It might require a change in workflow, but it will save you headaches in the long run. When it comes to admission status, things get a little trickier. Evaluation of the admission status includes “severity of illness” and “intensity of service.” Clearly, you have more to do with the determination of the latter than the former (at least we hope so), and that is where you will interact with the hospital’s utilization review service. Let’s focus on that for the time being.
Roughly, observation should be used for patients for whom stabilization and discharge are expected within 24 hours, the patient is hemodynamically stable, and the clinical diagnosis is unclear. It used to be that “obs”—or observation—was only used for 23 hours, but Medicare now allows up to 48 hours of observation. CMS has a list of initial diagnoses that they view as appropriate for obs, such as chest pain, CHF, and syncope.
On the inpatient side, here it is straight from CMS: “Inpatient care, rather than outpatient care, is required only if the beneficiary’s medical condition, safety, or health would be significantly and directly threatened if care was provided in a less intensive setting. Without accompanying medical conditions, factors that would only cause the beneficiary inconvenience in terms of time and money needed to care for the beneficiary at home or for travel to a physician’s office, or that may cause the beneficiary to worry, do not justify a continued hospital stay.” (You can read more by downloading this PDF: www.cms.gov/MLNMatters Articles/Downloads/SE1037.pdf.)
Beware, though: This is a bit like going down the rabbit hole—you can get lost in all the regulations and amendments. Which, to no one’s great surprise, explains why Milliman and Interqual operate such big businesses interpreting and applying these guidelines. We all know that you can’t control the phone calls coming from the ED. However, it is paramount that when you accept a patient, you document clearly and appropriately the admission status and the clinical criteria used to make your determination. Will everyone get it right every time? Probably not. Remember, though, that documentation will not only support the admission status, but also your professional fee billing.
Now what? Educate, educate, educate.
Ideally, you should meet with your case management/UR team and decide how to deliver the message to your group. Honestly, I think that a group responds better to explanations coming from one of their own rather than inviting the head of case management to come and speak for an hour. Rather than risk setting up an adversarial relationship with case management, consider filtering the message through your leadership. As a group leader, you need to be able to interpret hospital-driven directives and deliver the information to your group in a constructive manner. As working hospitalists, we need to understand the nonclinical factors that affect us—and our hospitals. It’s part of the job.
I was hoping someone would address Interqual criteria for admission. I have a pretty good knowledge about this and apply it to justify “intensity of service.” It seems that most ED docs don’t understand these criteria and, as a result, we end up having “too many obs,” per our CEO. What do I do? How do I get everyone on board the “hospitalist agenda wagon”?
I.U., Texas
Dr. Hospitalist responds: Many hospitals now use either Interqual or Milliman to help them make determinations as to whether a patient should be inpatient or observation. Regardless of the resource used, there should be some basic understanding as to what determines the admission status—namely, the “intensity of service,” as you describe.
First things first: I would not let the ED doc determine the admission status. The ED physician should continue to occupy their binary decision algorithm of 1) home and 2) admission. Once they decide on admission, they should make no further decisions regarding the care of the patient. Why? Well, they don’t work upstairs (or down the hall), and they generally have a poorer understanding than you do about admission status and the most appropriate unit for your patient.
Nationally, ED physicians (through American College of Emergency Physicians policy statements) have adopted the approach of no longer writing “admission” orders, instead calling them “transition” orders. I would do nothing to discourage this approach, even though it does make more work for us as hospitalists. So, as a starting point, you and your team should determine the admission location and the status. It might require a change in workflow, but it will save you headaches in the long run. When it comes to admission status, things get a little trickier. Evaluation of the admission status includes “severity of illness” and “intensity of service.” Clearly, you have more to do with the determination of the latter than the former (at least we hope so), and that is where you will interact with the hospital’s utilization review service. Let’s focus on that for the time being.
Roughly, observation should be used for patients for whom stabilization and discharge are expected within 24 hours, the patient is hemodynamically stable, and the clinical diagnosis is unclear. It used to be that “obs”—or observation—was only used for 23 hours, but Medicare now allows up to 48 hours of observation. CMS has a list of initial diagnoses that they view as appropriate for obs, such as chest pain, CHF, and syncope.
On the inpatient side, here it is straight from CMS: “Inpatient care, rather than outpatient care, is required only if the beneficiary’s medical condition, safety, or health would be significantly and directly threatened if care was provided in a less intensive setting. Without accompanying medical conditions, factors that would only cause the beneficiary inconvenience in terms of time and money needed to care for the beneficiary at home or for travel to a physician’s office, or that may cause the beneficiary to worry, do not justify a continued hospital stay.” (You can read more by downloading this PDF: www.cms.gov/MLNMatters Articles/Downloads/SE1037.pdf.)
Beware, though: This is a bit like going down the rabbit hole—you can get lost in all the regulations and amendments. Which, to no one’s great surprise, explains why Milliman and Interqual operate such big businesses interpreting and applying these guidelines. We all know that you can’t control the phone calls coming from the ED. However, it is paramount that when you accept a patient, you document clearly and appropriately the admission status and the clinical criteria used to make your determination. Will everyone get it right every time? Probably not. Remember, though, that documentation will not only support the admission status, but also your professional fee billing.
Now what? Educate, educate, educate.
Ideally, you should meet with your case management/UR team and decide how to deliver the message to your group. Honestly, I think that a group responds better to explanations coming from one of their own rather than inviting the head of case management to come and speak for an hour. Rather than risk setting up an adversarial relationship with case management, consider filtering the message through your leadership. As a group leader, you need to be able to interpret hospital-driven directives and deliver the information to your group in a constructive manner. As working hospitalists, we need to understand the nonclinical factors that affect us—and our hospitals. It’s part of the job.
ONLINE EXCLUSIVE: Hospitalists discuss how HM can improve patient satisfaction
ONLINE EXCLUSIVE: The Pros and Cons of a Super-Commuter Lifestyle
ONLINE EXCLUSIVE: A Discharge Solution—or Problem?
In a bit of counterintuition, an empty discharge lounge might be the most successful kind.
Christine Collins, executive director of patient access services at Brigham and Women’s Hospital in Boston, says that the lounge should be a service for discharged patients who have completed medical treatment, but who for some reason remain unable to leave the institution. Such cases can include waiting on a prescription from the pharmacy, or simply waiting on a relative or friend to arrive with transportation.
—Christine Collins, executive director, patient access services, Brigham and Women’s Hospital, Boston
She does not view Brigham’s discharge lounge, a room with lounge chairs and light meals that is staffed by a registered nurse, as the answer to the throughput conundrum hospitals across the country face each and every day. So when the lounge is empty, it means patients have been discharged without any hang-ups.
“It’s not a patient-care area,” Collins says. “They’re people that should be home.”
Some view discharge lounges as a potential aid in smoothing out the discharge process. In theory, patients ready to be medically discharged but unable to leave the hospital have a place to go. But keeping the patients in the building, and under the eye of a nurse, could create liability issues, says Ken Simone, DO, SFHM, president of Hospitalist and Practice Solutions in Veazie, Maine, and a member of Team Hospitalist. Dr. Simone also wonders how the lounge concept impacts patient satisfaction, as some could view it negatively if they’re told they have to sit in what could be construed as a back-end waiting room.
“People need to assess what they’re doing it for and is it really accomplishing what they want it to accomplish,” Collins says.
Discharge lounges “can’t be another nursing unit because a patient is supposed to be discharged. ... Whether you have a discharge lounge or not, you need to improve your systems so that the patients leave when they leave.”
Richard Quinn is a freelance writer based in New Jersey.
In a bit of counterintuition, an empty discharge lounge might be the most successful kind.
Christine Collins, executive director of patient access services at Brigham and Women’s Hospital in Boston, says that the lounge should be a service for discharged patients who have completed medical treatment, but who for some reason remain unable to leave the institution. Such cases can include waiting on a prescription from the pharmacy, or simply waiting on a relative or friend to arrive with transportation.
—Christine Collins, executive director, patient access services, Brigham and Women’s Hospital, Boston
She does not view Brigham’s discharge lounge, a room with lounge chairs and light meals that is staffed by a registered nurse, as the answer to the throughput conundrum hospitals across the country face each and every day. So when the lounge is empty, it means patients have been discharged without any hang-ups.
“It’s not a patient-care area,” Collins says. “They’re people that should be home.”
Some view discharge lounges as a potential aid in smoothing out the discharge process. In theory, patients ready to be medically discharged but unable to leave the hospital have a place to go. But keeping the patients in the building, and under the eye of a nurse, could create liability issues, says Ken Simone, DO, SFHM, president of Hospitalist and Practice Solutions in Veazie, Maine, and a member of Team Hospitalist. Dr. Simone also wonders how the lounge concept impacts patient satisfaction, as some could view it negatively if they’re told they have to sit in what could be construed as a back-end waiting room.
“People need to assess what they’re doing it for and is it really accomplishing what they want it to accomplish,” Collins says.
Discharge lounges “can’t be another nursing unit because a patient is supposed to be discharged. ... Whether you have a discharge lounge or not, you need to improve your systems so that the patients leave when they leave.”
Richard Quinn is a freelance writer based in New Jersey.
In a bit of counterintuition, an empty discharge lounge might be the most successful kind.
Christine Collins, executive director of patient access services at Brigham and Women’s Hospital in Boston, says that the lounge should be a service for discharged patients who have completed medical treatment, but who for some reason remain unable to leave the institution. Such cases can include waiting on a prescription from the pharmacy, or simply waiting on a relative or friend to arrive with transportation.
—Christine Collins, executive director, patient access services, Brigham and Women’s Hospital, Boston
She does not view Brigham’s discharge lounge, a room with lounge chairs and light meals that is staffed by a registered nurse, as the answer to the throughput conundrum hospitals across the country face each and every day. So when the lounge is empty, it means patients have been discharged without any hang-ups.
“It’s not a patient-care area,” Collins says. “They’re people that should be home.”
Some view discharge lounges as a potential aid in smoothing out the discharge process. In theory, patients ready to be medically discharged but unable to leave the hospital have a place to go. But keeping the patients in the building, and under the eye of a nurse, could create liability issues, says Ken Simone, DO, SFHM, president of Hospitalist and Practice Solutions in Veazie, Maine, and a member of Team Hospitalist. Dr. Simone also wonders how the lounge concept impacts patient satisfaction, as some could view it negatively if they’re told they have to sit in what could be construed as a back-end waiting room.
“People need to assess what they’re doing it for and is it really accomplishing what they want it to accomplish,” Collins says.
Discharge lounges “can’t be another nursing unit because a patient is supposed to be discharged. ... Whether you have a discharge lounge or not, you need to improve your systems so that the patients leave when they leave.”
Richard Quinn is a freelance writer based in New Jersey.
ONLINE EXCLUSIVE: Experts discuss strategies to improve early discharges
ONLINE EXCLUSIVE TK
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A new ICU paradigm: Intensivists as primary critical care physicians
After nearly a half-century, the subspecialty of critical care medicine—uniquely trained physicians caring for critically ill or injured patients in specialized, discrete nursing units—continues to suffer from an identity crisis.
Too often, the role of the intensivist in caring for the patient is unclear, to the patient, to the family, and to other physicians. Is the intensivist merely a consultant, or does he or she have a larger role?
The time has come to end the identity crisis with a fundamental paradigm shift, to identify intensivists as the principal caregivers of critically ill patients, ie, the “primary critical care physicians,” or PCCPs. We think this is necessary based not only on evidence from clinical studies, but also on our decades of experience as intensivist caregivers in a high-intensity, closed-staffing model.
REASONS FOR THE IDENTITY CRISIS
The reasons for the continued identity crisis of intensivists are many and complex.
To begin with, other physicians tend to be ambiguous about the duties of intensivists, and the general population is mostly unaware of the subspecialty. In contrast to mature subspecialties such as cardiology or gastroenterology, where responsibilities are generally known to physicians and the lay public alike, or in contrast even to recently evolved specialties such as emergency medicine, the enigmatic roles of an intensivist may differ depending on primary specialty (anesthesiology, internal medicine, surgery) and the patient population, or even among intensive care units (ICUs) within the same hospital.
Moreover, that an identity crisis exists is even more surprising given the disproportionately large consumption by critical care medicine of finite economic resources. One would expect that a sector of health care that expends 1% of the GNP1 would have clearly explicit roles and responsibilities for its physicians.
Nearly three-quarters of the care by intensivists in the United States is delivered in what is considered an “open” or “low-intensity” ICU staffing model2: an intensivist makes treatment recommendations but otherwise has no overarching authority over patient care. In this model, the admitting physician is not trained in critical care and is not available throughout the day to make decisions concerning the management of the patient. In addition, various consulting physicians and single-organ specialists may not be aware of the overall management plan, resulting in potentially unnecessary or conflicting orders and increased expense.2 What is more, in an open ICU model, critical care nurses are often left to detect and correct a significant change in a patient’s status without the necessary immediate physician availability, resulting not only in a stressful working environment for nursing staff, but also in potential harm associated with individuals providing care outside their scope of practice.3
In only a small percentage of ICUs—mostly medical ICUs and ICUs in teaching hospitals—is critical care provided in a “high-intensity” or “closed” staffing pattern, in which treatment decisions are cohesively managed under the guidance of an intensivist.2
EVIDENCE IN THE MEDICAL LITERATURE
Staffing patterns in the ICU
Several studies have attempted to identify the consequences of these different ICU staffing patterns on patient care.
Hanson et al4 examined two concurrent patient cohorts admitted to a surgical ICU. The study cohort was cared for by an on-site critical care team supervised by an intensivist, while the control cohort received care from a team with patient care responsibilities in multiple sites, supervised by a general surgeon. The results showed that patients cared for by the critical care team spent less time in the ICU, used fewer resources, had fewer complications, and had lower total hospital charges. The difference between the two cohorts was most evident in patients with the worst Acute Physiology and Chronic Health Evaluation (APACHE) II scores.
According to Hanson et al, the lack of an accepted prototype for the delivery of critical care is due to factors such as the relative youth of the discipline, contention over control of individual patient management, and the absence of a single academic advocate.4
Moreover, Pronovost et al5 concluded that high-intensity staffing (mandatory intensivist consultation or closed ICU) was associated with lower ICU mortality rates in 93% of studies and with a reduced ICU length of stay in the high-intensity staffing units when compared with ICUs with low-intensity staffing (no intensivist or elective intensivist consultation).
Critics of our PCCP paradigm may point to a study by Levy et al6 that, using a database of more than 100,000 patients, could not demonstrate any survival benefit with management by critical care physicians. Indeed the study found that patients managed by intensivists had a higher mortality rate than patients managed by physicians not trained in critical care. However, they also showed that more patients managed for the entire stay by intensivists received interventions such as intravenous drugs, mechanical ventilation, and continuous sedation and that they had a higher mean severity of illness as measured by the expanded Simplified Acute Physiology Score (SAPS II) and higher hospital mortality rates than patients who were not managed by a critical care team.
According to Levy et al, most ICUs in the United States are structured as completely open units in which the admitting physicians retain full clinical and decisional responsibility and thus have the option to care for their patients with or without input from intensivists.6
However, a recent study by Kim et al7 likely rebuts the findings of Levy et al. Kim et al analyzed more than 100,000 ICU admissions and found that the lowest odds of death within 30 days were in ICUs that had high-intensity physician staffing and multidisciplinary care teams, suggesting that the presence of an intensivist confers a survival benefit.
Other studies have also shown that high-intensity staffing improves patient outcomes in the ICU.5,8,9
Issues of cost and use of resources
Issues concerning cost and human resources for staffing ICUs have acquired increasing importance. According to Angus et al,10 intensivists provided care to only 36.8% of all ICU patients. The demand for critical care services will continue to grow rapidly as the population ages. It is this shift in the care of the critically ill that requires intensivists to take on the role of the PCCP, so as to provide high-quality, evidence-based critical care and to promote a long-term sustainable model of physician and nursing care.
OUR EXPERIENCE
Our intensivist group has been providing a near-primary-care style of critical care practice for almost 40 years, from its inception in 1977 by one of the authors (A.B.), to our current group of 15 board-certified intensivists. We can easily cite the clinical value of our practice approach, with outcome data showing consistent and better-than-expected Standardized Mortality Ratio accounts from our APACHE IV data (personal communication, Cleveland Clinic Cerner/APACHE IV report), or with reports showing that the presence of a full-time, attending-level, in-house staff physician ensures that patients, surgeons, and consultants have confidence and respect for the care provided. However, we feel that the intangible components are what make our practice a prototype for the PCCP model.
A dedicated team with a low turnover rate
First, we have a team of anesthesiology- and surgery-based intensivists dedicated to ICU practice, with a very low turnover or burnout rate, in contrast to most ICUs in the United States, where intensivists tend to practice part-time (at other times either providing operating-room-based anesthesia or surgical care or working in a pulmonary- or sleep-lab-based practice). We believe this point should not go unstressed: we have a team of physicians who have dedicated their career to working in the ICU full-time, and some have done so in excess of 20 years, even as long as 30 years! It is our opinion that we are able to provide such a highly desirable working environment by a unique daily staffing model that does not utilize the conventional practice style of one intensivist on-call per week.
We also feel that our model dramatically reduces the risk of burnout by permitting our attending intensivists to break up on-call sequences so that there are days on which work in the ICU is not also associated with on-call responsibilities.
A successful fellowship program
Second, we have an extremely successful fellowship program, which began in 1974 when one of the authors (A.B.) advocated the training of anesthesiology residents as intensivists.11 The American Board of Anesthesiology certifies on average 55 candidates per year in critical care medicine, and our program trains about 10% of the physicians applying for certification. In most years, there are actually more candidates for our program than there are available positions, which is atypical for anesthesiology-based critical care training programs. This wealth of young, talented candidates interested in critical care as a career is, again, in contrast to most anesthesiology-based programs, which find it difficult to enroll even one fellow per year.
Critical care programs grounded in anesthesiology typically struggle because of the realities of economics.12 The payoff of operating-room-based anesthesiology practices generally outshines those in critical care, yet we already have three times as many candidates as there are positions to start our training program in the next 2 years. We feel that candidates are attracted to our program simply because our environment (dedicated staffing, equal clinical footing with surgeons, low burnout rates) is seen as an exciting, positively charged role-modeling atmosphere for young physicians who may have a career interest that involves more than just their original base specialty.
A collegial working relationship
Third, we have a thriving, collegial working relationship—including daily bedside and weekly bioethics rounds with our nursing staff—which has fueled a high degree of professional satisfaction among nurses. This is evidenced by the extremely low turnover rate of nurses (less than 5% per year in the last 5 years) and by national recognition for nursing excellence (Beacon Award for Critical Care Excellence, American Association of Critical Care Nurses) (personal communication, S. Wilson, Nurse Manager). In 2009, the four nurses out of 174 who left did so to further their careers.
While low turnover rates among nurses and award-winning practices are surely a testament to a highly motivated and skilled nursing team, there is no question that a constructive collegiality among the physicians and nurses has provided an environment to allow these positive aspects to flourish.
OVERCOMING ROADBLOCKS
Obviously, although in theory it is easy to proclaim a PCCP paradigm, in reality the roadblocks are many.
For example, standardization of education and credentialing would be an essential hurdle to overcome. The current educational arrangement of the various adult specialties (anesthesiology, internal medicine, surgery), each offering disparate subspecialty critical care training and certification, is deeply rooted in interdisciplinary politics, but without any demonstration of improved patient care.13 As described recently by Kaplan and Shaw,14 an all-encompassing training and credentialing standard for critical care is essential for 21st century medicine and would go a long way toward development of the PCCP paradigm.
Another major roadblock is the shortage of intensivists in the United States.13 There are many reasons why physicians opt not to select critical care as a career, such as a non-straight-forward training pathway (as described above), recognition that the 24-hours per day, 7-days-per-week nature of critical care affects lifestyle issues, and inconsistent physician compensation.13
However, technological and personnel advances, including the use of electronic (e-ICU)15 and mid-level practitioner models, have led to creative approaches to extend critical care coverage.13
Additionally, the multitude of physician specialty stakeholders and the overall flux of the future of medical care in the United States all would contribute to the difficulties of prioritizing the implementation of the PCCP concept. Also, our practice style—a large intensivist group working in an ostensibly closed surgical ICU in a tertiary-care hospital—is one possible model, as is the even more highly evolved Cleveland Clinic medical ICU, where medical intensivists are already essentially PCCPs. But these models of care may not be generalizable among the local care patterns and medical politics across hospitals or ICUs.
Based on the described successes of our practice model, coupled with evidence in the literature, we have proposed a paradigm shift toward the concept of a PCCP. To be sure, paradigm shifts nearly always require time, effort, and wherewithal. In the end, however, we feel that embracement of the PCCP paradigm would result in a concise, discrete understanding of the role of intensivist, eliminate the specialty’s identity crisis, and ultimately improve patient care.
- Bloomfield EL. The impact of economics on changing medical technology with reference to critical care medicine in the United States. Anesth Analg 2003; 96:418–425.
- Gajic O, Afessa B. Physician staffing models and patient safety in the ICU. Chest 2009; 135:1038–1044.
- Baggs JG, Schmitt MH, Mushlin AI, et al. Association between nurse-physician collaboration and patient outcomes in three intensive care units. Crit Care Med 1999; 27:1991–1998.
- Hanson CW, Deutschman CS, Anderson HL, et al. Effects of an organized critical care service on outcomes and resource utilization: a cohort study. Crit Care Med 1999; 27:270–274.
- Pronovost PJ, Angus DC, Dorman T, Robinson KA, Dremsizov TT, Young TL. Physician staffing patterns and clinical outcomes in critically ill patients: a systematic review. JAMA 2002; 288:2151–2162.
- Levy MM, Rapoport J, Lemeshow S, Chalfin DB, Phillips G, Danis M. Association between critical care physician management and patient mortality in the intensive care unit. Ann Intern Med 2008; 148:801–809.
- Kim MM, Barnato AE, Angus DC, Fleisher LA, Kahn JM. The effect of multidisciplinary care teams on intensive care unit mortality. Arch Intern Med 2010; 170:369–376.
- Carson SS, Stocking C, Podsadecki T, et al. Effects of organizational change in the medical intensive care unit of a teaching hospital: a comparison of ‘open’ and ‘closed’ formats. JAMA 1996; 276:322–328.
- Treggiari MM, Martin DP, Yanez ND, Caldwell E, Hudson LD, Rubenfeld GD. Effect of intensive care unit organizational model and structure on outcomes in patients with acute lung injury. Am J Respir Crit Care Med 2007; 176:685–690.
- Angus DC, Kelley MA, Schmitz RJ, White A, Popovich J; Committee on Manpower for Pulmonary and Critical Care Societies (COMPACCS). Caring for the critically ill patient. Current and projected workforce requirements for care of the critically ill and patients with pulmonary disease: can we meet the requirements of an aging population? JAMA 2000; 284:2762–2770.
- Boutros AR. Anesthesiology and intensive care (editorial). Anesthesiology 1974; 41:319–320.
- Boyle WA. A critical time for anesthesiology? American Society of Anesthesiologists (ASA) Newsletter, September 2009;10–11. http://viewer.zmags.com/publication/9960917c#/9960917c/12. Accessed July 13, 2011.
- Ewart GW, Marcus L, Gaba MM, Bradner RH, Medina JL, Chandler EB. The critical care medicine crisis: a call for federal action: a white paper from the critical care professional societies. Chest 2004; 125:1518–1521.
- Kaplan LJ, Shaw AD. Standards for education and credentialing in critical care medicine. JAMA 2011; 305:296–297.
- Leong JR, Sirio CA, Rotondi AJ. eICU program favorably affects clinical and economic outcomes. Crit Care 2005, http://ccforum.com/content/9/5/E22. Accessed July 13, 2011.
After nearly a half-century, the subspecialty of critical care medicine—uniquely trained physicians caring for critically ill or injured patients in specialized, discrete nursing units—continues to suffer from an identity crisis.
Too often, the role of the intensivist in caring for the patient is unclear, to the patient, to the family, and to other physicians. Is the intensivist merely a consultant, or does he or she have a larger role?
The time has come to end the identity crisis with a fundamental paradigm shift, to identify intensivists as the principal caregivers of critically ill patients, ie, the “primary critical care physicians,” or PCCPs. We think this is necessary based not only on evidence from clinical studies, but also on our decades of experience as intensivist caregivers in a high-intensity, closed-staffing model.
REASONS FOR THE IDENTITY CRISIS
The reasons for the continued identity crisis of intensivists are many and complex.
To begin with, other physicians tend to be ambiguous about the duties of intensivists, and the general population is mostly unaware of the subspecialty. In contrast to mature subspecialties such as cardiology or gastroenterology, where responsibilities are generally known to physicians and the lay public alike, or in contrast even to recently evolved specialties such as emergency medicine, the enigmatic roles of an intensivist may differ depending on primary specialty (anesthesiology, internal medicine, surgery) and the patient population, or even among intensive care units (ICUs) within the same hospital.
Moreover, that an identity crisis exists is even more surprising given the disproportionately large consumption by critical care medicine of finite economic resources. One would expect that a sector of health care that expends 1% of the GNP1 would have clearly explicit roles and responsibilities for its physicians.
Nearly three-quarters of the care by intensivists in the United States is delivered in what is considered an “open” or “low-intensity” ICU staffing model2: an intensivist makes treatment recommendations but otherwise has no overarching authority over patient care. In this model, the admitting physician is not trained in critical care and is not available throughout the day to make decisions concerning the management of the patient. In addition, various consulting physicians and single-organ specialists may not be aware of the overall management plan, resulting in potentially unnecessary or conflicting orders and increased expense.2 What is more, in an open ICU model, critical care nurses are often left to detect and correct a significant change in a patient’s status without the necessary immediate physician availability, resulting not only in a stressful working environment for nursing staff, but also in potential harm associated with individuals providing care outside their scope of practice.3
In only a small percentage of ICUs—mostly medical ICUs and ICUs in teaching hospitals—is critical care provided in a “high-intensity” or “closed” staffing pattern, in which treatment decisions are cohesively managed under the guidance of an intensivist.2
EVIDENCE IN THE MEDICAL LITERATURE
Staffing patterns in the ICU
Several studies have attempted to identify the consequences of these different ICU staffing patterns on patient care.
Hanson et al4 examined two concurrent patient cohorts admitted to a surgical ICU. The study cohort was cared for by an on-site critical care team supervised by an intensivist, while the control cohort received care from a team with patient care responsibilities in multiple sites, supervised by a general surgeon. The results showed that patients cared for by the critical care team spent less time in the ICU, used fewer resources, had fewer complications, and had lower total hospital charges. The difference between the two cohorts was most evident in patients with the worst Acute Physiology and Chronic Health Evaluation (APACHE) II scores.
According to Hanson et al, the lack of an accepted prototype for the delivery of critical care is due to factors such as the relative youth of the discipline, contention over control of individual patient management, and the absence of a single academic advocate.4
Moreover, Pronovost et al5 concluded that high-intensity staffing (mandatory intensivist consultation or closed ICU) was associated with lower ICU mortality rates in 93% of studies and with a reduced ICU length of stay in the high-intensity staffing units when compared with ICUs with low-intensity staffing (no intensivist or elective intensivist consultation).
Critics of our PCCP paradigm may point to a study by Levy et al6 that, using a database of more than 100,000 patients, could not demonstrate any survival benefit with management by critical care physicians. Indeed the study found that patients managed by intensivists had a higher mortality rate than patients managed by physicians not trained in critical care. However, they also showed that more patients managed for the entire stay by intensivists received interventions such as intravenous drugs, mechanical ventilation, and continuous sedation and that they had a higher mean severity of illness as measured by the expanded Simplified Acute Physiology Score (SAPS II) and higher hospital mortality rates than patients who were not managed by a critical care team.
According to Levy et al, most ICUs in the United States are structured as completely open units in which the admitting physicians retain full clinical and decisional responsibility and thus have the option to care for their patients with or without input from intensivists.6
However, a recent study by Kim et al7 likely rebuts the findings of Levy et al. Kim et al analyzed more than 100,000 ICU admissions and found that the lowest odds of death within 30 days were in ICUs that had high-intensity physician staffing and multidisciplinary care teams, suggesting that the presence of an intensivist confers a survival benefit.
Other studies have also shown that high-intensity staffing improves patient outcomes in the ICU.5,8,9
Issues of cost and use of resources
Issues concerning cost and human resources for staffing ICUs have acquired increasing importance. According to Angus et al,10 intensivists provided care to only 36.8% of all ICU patients. The demand for critical care services will continue to grow rapidly as the population ages. It is this shift in the care of the critically ill that requires intensivists to take on the role of the PCCP, so as to provide high-quality, evidence-based critical care and to promote a long-term sustainable model of physician and nursing care.
OUR EXPERIENCE
Our intensivist group has been providing a near-primary-care style of critical care practice for almost 40 years, from its inception in 1977 by one of the authors (A.B.), to our current group of 15 board-certified intensivists. We can easily cite the clinical value of our practice approach, with outcome data showing consistent and better-than-expected Standardized Mortality Ratio accounts from our APACHE IV data (personal communication, Cleveland Clinic Cerner/APACHE IV report), or with reports showing that the presence of a full-time, attending-level, in-house staff physician ensures that patients, surgeons, and consultants have confidence and respect for the care provided. However, we feel that the intangible components are what make our practice a prototype for the PCCP model.
A dedicated team with a low turnover rate
First, we have a team of anesthesiology- and surgery-based intensivists dedicated to ICU practice, with a very low turnover or burnout rate, in contrast to most ICUs in the United States, where intensivists tend to practice part-time (at other times either providing operating-room-based anesthesia or surgical care or working in a pulmonary- or sleep-lab-based practice). We believe this point should not go unstressed: we have a team of physicians who have dedicated their career to working in the ICU full-time, and some have done so in excess of 20 years, even as long as 30 years! It is our opinion that we are able to provide such a highly desirable working environment by a unique daily staffing model that does not utilize the conventional practice style of one intensivist on-call per week.
We also feel that our model dramatically reduces the risk of burnout by permitting our attending intensivists to break up on-call sequences so that there are days on which work in the ICU is not also associated with on-call responsibilities.
A successful fellowship program
Second, we have an extremely successful fellowship program, which began in 1974 when one of the authors (A.B.) advocated the training of anesthesiology residents as intensivists.11 The American Board of Anesthesiology certifies on average 55 candidates per year in critical care medicine, and our program trains about 10% of the physicians applying for certification. In most years, there are actually more candidates for our program than there are available positions, which is atypical for anesthesiology-based critical care training programs. This wealth of young, talented candidates interested in critical care as a career is, again, in contrast to most anesthesiology-based programs, which find it difficult to enroll even one fellow per year.
Critical care programs grounded in anesthesiology typically struggle because of the realities of economics.12 The payoff of operating-room-based anesthesiology practices generally outshines those in critical care, yet we already have three times as many candidates as there are positions to start our training program in the next 2 years. We feel that candidates are attracted to our program simply because our environment (dedicated staffing, equal clinical footing with surgeons, low burnout rates) is seen as an exciting, positively charged role-modeling atmosphere for young physicians who may have a career interest that involves more than just their original base specialty.
A collegial working relationship
Third, we have a thriving, collegial working relationship—including daily bedside and weekly bioethics rounds with our nursing staff—which has fueled a high degree of professional satisfaction among nurses. This is evidenced by the extremely low turnover rate of nurses (less than 5% per year in the last 5 years) and by national recognition for nursing excellence (Beacon Award for Critical Care Excellence, American Association of Critical Care Nurses) (personal communication, S. Wilson, Nurse Manager). In 2009, the four nurses out of 174 who left did so to further their careers.
While low turnover rates among nurses and award-winning practices are surely a testament to a highly motivated and skilled nursing team, there is no question that a constructive collegiality among the physicians and nurses has provided an environment to allow these positive aspects to flourish.
OVERCOMING ROADBLOCKS
Obviously, although in theory it is easy to proclaim a PCCP paradigm, in reality the roadblocks are many.
For example, standardization of education and credentialing would be an essential hurdle to overcome. The current educational arrangement of the various adult specialties (anesthesiology, internal medicine, surgery), each offering disparate subspecialty critical care training and certification, is deeply rooted in interdisciplinary politics, but without any demonstration of improved patient care.13 As described recently by Kaplan and Shaw,14 an all-encompassing training and credentialing standard for critical care is essential for 21st century medicine and would go a long way toward development of the PCCP paradigm.
Another major roadblock is the shortage of intensivists in the United States.13 There are many reasons why physicians opt not to select critical care as a career, such as a non-straight-forward training pathway (as described above), recognition that the 24-hours per day, 7-days-per-week nature of critical care affects lifestyle issues, and inconsistent physician compensation.13
However, technological and personnel advances, including the use of electronic (e-ICU)15 and mid-level practitioner models, have led to creative approaches to extend critical care coverage.13
Additionally, the multitude of physician specialty stakeholders and the overall flux of the future of medical care in the United States all would contribute to the difficulties of prioritizing the implementation of the PCCP concept. Also, our practice style—a large intensivist group working in an ostensibly closed surgical ICU in a tertiary-care hospital—is one possible model, as is the even more highly evolved Cleveland Clinic medical ICU, where medical intensivists are already essentially PCCPs. But these models of care may not be generalizable among the local care patterns and medical politics across hospitals or ICUs.
Based on the described successes of our practice model, coupled with evidence in the literature, we have proposed a paradigm shift toward the concept of a PCCP. To be sure, paradigm shifts nearly always require time, effort, and wherewithal. In the end, however, we feel that embracement of the PCCP paradigm would result in a concise, discrete understanding of the role of intensivist, eliminate the specialty’s identity crisis, and ultimately improve patient care.
After nearly a half-century, the subspecialty of critical care medicine—uniquely trained physicians caring for critically ill or injured patients in specialized, discrete nursing units—continues to suffer from an identity crisis.
Too often, the role of the intensivist in caring for the patient is unclear, to the patient, to the family, and to other physicians. Is the intensivist merely a consultant, or does he or she have a larger role?
The time has come to end the identity crisis with a fundamental paradigm shift, to identify intensivists as the principal caregivers of critically ill patients, ie, the “primary critical care physicians,” or PCCPs. We think this is necessary based not only on evidence from clinical studies, but also on our decades of experience as intensivist caregivers in a high-intensity, closed-staffing model.
REASONS FOR THE IDENTITY CRISIS
The reasons for the continued identity crisis of intensivists are many and complex.
To begin with, other physicians tend to be ambiguous about the duties of intensivists, and the general population is mostly unaware of the subspecialty. In contrast to mature subspecialties such as cardiology or gastroenterology, where responsibilities are generally known to physicians and the lay public alike, or in contrast even to recently evolved specialties such as emergency medicine, the enigmatic roles of an intensivist may differ depending on primary specialty (anesthesiology, internal medicine, surgery) and the patient population, or even among intensive care units (ICUs) within the same hospital.
Moreover, that an identity crisis exists is even more surprising given the disproportionately large consumption by critical care medicine of finite economic resources. One would expect that a sector of health care that expends 1% of the GNP1 would have clearly explicit roles and responsibilities for its physicians.
Nearly three-quarters of the care by intensivists in the United States is delivered in what is considered an “open” or “low-intensity” ICU staffing model2: an intensivist makes treatment recommendations but otherwise has no overarching authority over patient care. In this model, the admitting physician is not trained in critical care and is not available throughout the day to make decisions concerning the management of the patient. In addition, various consulting physicians and single-organ specialists may not be aware of the overall management plan, resulting in potentially unnecessary or conflicting orders and increased expense.2 What is more, in an open ICU model, critical care nurses are often left to detect and correct a significant change in a patient’s status without the necessary immediate physician availability, resulting not only in a stressful working environment for nursing staff, but also in potential harm associated with individuals providing care outside their scope of practice.3
In only a small percentage of ICUs—mostly medical ICUs and ICUs in teaching hospitals—is critical care provided in a “high-intensity” or “closed” staffing pattern, in which treatment decisions are cohesively managed under the guidance of an intensivist.2
EVIDENCE IN THE MEDICAL LITERATURE
Staffing patterns in the ICU
Several studies have attempted to identify the consequences of these different ICU staffing patterns on patient care.
Hanson et al4 examined two concurrent patient cohorts admitted to a surgical ICU. The study cohort was cared for by an on-site critical care team supervised by an intensivist, while the control cohort received care from a team with patient care responsibilities in multiple sites, supervised by a general surgeon. The results showed that patients cared for by the critical care team spent less time in the ICU, used fewer resources, had fewer complications, and had lower total hospital charges. The difference between the two cohorts was most evident in patients with the worst Acute Physiology and Chronic Health Evaluation (APACHE) II scores.
According to Hanson et al, the lack of an accepted prototype for the delivery of critical care is due to factors such as the relative youth of the discipline, contention over control of individual patient management, and the absence of a single academic advocate.4
Moreover, Pronovost et al5 concluded that high-intensity staffing (mandatory intensivist consultation or closed ICU) was associated with lower ICU mortality rates in 93% of studies and with a reduced ICU length of stay in the high-intensity staffing units when compared with ICUs with low-intensity staffing (no intensivist or elective intensivist consultation).
Critics of our PCCP paradigm may point to a study by Levy et al6 that, using a database of more than 100,000 patients, could not demonstrate any survival benefit with management by critical care physicians. Indeed the study found that patients managed by intensivists had a higher mortality rate than patients managed by physicians not trained in critical care. However, they also showed that more patients managed for the entire stay by intensivists received interventions such as intravenous drugs, mechanical ventilation, and continuous sedation and that they had a higher mean severity of illness as measured by the expanded Simplified Acute Physiology Score (SAPS II) and higher hospital mortality rates than patients who were not managed by a critical care team.
According to Levy et al, most ICUs in the United States are structured as completely open units in which the admitting physicians retain full clinical and decisional responsibility and thus have the option to care for their patients with or without input from intensivists.6
However, a recent study by Kim et al7 likely rebuts the findings of Levy et al. Kim et al analyzed more than 100,000 ICU admissions and found that the lowest odds of death within 30 days were in ICUs that had high-intensity physician staffing and multidisciplinary care teams, suggesting that the presence of an intensivist confers a survival benefit.
Other studies have also shown that high-intensity staffing improves patient outcomes in the ICU.5,8,9
Issues of cost and use of resources
Issues concerning cost and human resources for staffing ICUs have acquired increasing importance. According to Angus et al,10 intensivists provided care to only 36.8% of all ICU patients. The demand for critical care services will continue to grow rapidly as the population ages. It is this shift in the care of the critically ill that requires intensivists to take on the role of the PCCP, so as to provide high-quality, evidence-based critical care and to promote a long-term sustainable model of physician and nursing care.
OUR EXPERIENCE
Our intensivist group has been providing a near-primary-care style of critical care practice for almost 40 years, from its inception in 1977 by one of the authors (A.B.), to our current group of 15 board-certified intensivists. We can easily cite the clinical value of our practice approach, with outcome data showing consistent and better-than-expected Standardized Mortality Ratio accounts from our APACHE IV data (personal communication, Cleveland Clinic Cerner/APACHE IV report), or with reports showing that the presence of a full-time, attending-level, in-house staff physician ensures that patients, surgeons, and consultants have confidence and respect for the care provided. However, we feel that the intangible components are what make our practice a prototype for the PCCP model.
A dedicated team with a low turnover rate
First, we have a team of anesthesiology- and surgery-based intensivists dedicated to ICU practice, with a very low turnover or burnout rate, in contrast to most ICUs in the United States, where intensivists tend to practice part-time (at other times either providing operating-room-based anesthesia or surgical care or working in a pulmonary- or sleep-lab-based practice). We believe this point should not go unstressed: we have a team of physicians who have dedicated their career to working in the ICU full-time, and some have done so in excess of 20 years, even as long as 30 years! It is our opinion that we are able to provide such a highly desirable working environment by a unique daily staffing model that does not utilize the conventional practice style of one intensivist on-call per week.
We also feel that our model dramatically reduces the risk of burnout by permitting our attending intensivists to break up on-call sequences so that there are days on which work in the ICU is not also associated with on-call responsibilities.
A successful fellowship program
Second, we have an extremely successful fellowship program, which began in 1974 when one of the authors (A.B.) advocated the training of anesthesiology residents as intensivists.11 The American Board of Anesthesiology certifies on average 55 candidates per year in critical care medicine, and our program trains about 10% of the physicians applying for certification. In most years, there are actually more candidates for our program than there are available positions, which is atypical for anesthesiology-based critical care training programs. This wealth of young, talented candidates interested in critical care as a career is, again, in contrast to most anesthesiology-based programs, which find it difficult to enroll even one fellow per year.
Critical care programs grounded in anesthesiology typically struggle because of the realities of economics.12 The payoff of operating-room-based anesthesiology practices generally outshines those in critical care, yet we already have three times as many candidates as there are positions to start our training program in the next 2 years. We feel that candidates are attracted to our program simply because our environment (dedicated staffing, equal clinical footing with surgeons, low burnout rates) is seen as an exciting, positively charged role-modeling atmosphere for young physicians who may have a career interest that involves more than just their original base specialty.
A collegial working relationship
Third, we have a thriving, collegial working relationship—including daily bedside and weekly bioethics rounds with our nursing staff—which has fueled a high degree of professional satisfaction among nurses. This is evidenced by the extremely low turnover rate of nurses (less than 5% per year in the last 5 years) and by national recognition for nursing excellence (Beacon Award for Critical Care Excellence, American Association of Critical Care Nurses) (personal communication, S. Wilson, Nurse Manager). In 2009, the four nurses out of 174 who left did so to further their careers.
While low turnover rates among nurses and award-winning practices are surely a testament to a highly motivated and skilled nursing team, there is no question that a constructive collegiality among the physicians and nurses has provided an environment to allow these positive aspects to flourish.
OVERCOMING ROADBLOCKS
Obviously, although in theory it is easy to proclaim a PCCP paradigm, in reality the roadblocks are many.
For example, standardization of education and credentialing would be an essential hurdle to overcome. The current educational arrangement of the various adult specialties (anesthesiology, internal medicine, surgery), each offering disparate subspecialty critical care training and certification, is deeply rooted in interdisciplinary politics, but without any demonstration of improved patient care.13 As described recently by Kaplan and Shaw,14 an all-encompassing training and credentialing standard for critical care is essential for 21st century medicine and would go a long way toward development of the PCCP paradigm.
Another major roadblock is the shortage of intensivists in the United States.13 There are many reasons why physicians opt not to select critical care as a career, such as a non-straight-forward training pathway (as described above), recognition that the 24-hours per day, 7-days-per-week nature of critical care affects lifestyle issues, and inconsistent physician compensation.13
However, technological and personnel advances, including the use of electronic (e-ICU)15 and mid-level practitioner models, have led to creative approaches to extend critical care coverage.13
Additionally, the multitude of physician specialty stakeholders and the overall flux of the future of medical care in the United States all would contribute to the difficulties of prioritizing the implementation of the PCCP concept. Also, our practice style—a large intensivist group working in an ostensibly closed surgical ICU in a tertiary-care hospital—is one possible model, as is the even more highly evolved Cleveland Clinic medical ICU, where medical intensivists are already essentially PCCPs. But these models of care may not be generalizable among the local care patterns and medical politics across hospitals or ICUs.
Based on the described successes of our practice model, coupled with evidence in the literature, we have proposed a paradigm shift toward the concept of a PCCP. To be sure, paradigm shifts nearly always require time, effort, and wherewithal. In the end, however, we feel that embracement of the PCCP paradigm would result in a concise, discrete understanding of the role of intensivist, eliminate the specialty’s identity crisis, and ultimately improve patient care.
- Bloomfield EL. The impact of economics on changing medical technology with reference to critical care medicine in the United States. Anesth Analg 2003; 96:418–425.
- Gajic O, Afessa B. Physician staffing models and patient safety in the ICU. Chest 2009; 135:1038–1044.
- Baggs JG, Schmitt MH, Mushlin AI, et al. Association between nurse-physician collaboration and patient outcomes in three intensive care units. Crit Care Med 1999; 27:1991–1998.
- Hanson CW, Deutschman CS, Anderson HL, et al. Effects of an organized critical care service on outcomes and resource utilization: a cohort study. Crit Care Med 1999; 27:270–274.
- Pronovost PJ, Angus DC, Dorman T, Robinson KA, Dremsizov TT, Young TL. Physician staffing patterns and clinical outcomes in critically ill patients: a systematic review. JAMA 2002; 288:2151–2162.
- Levy MM, Rapoport J, Lemeshow S, Chalfin DB, Phillips G, Danis M. Association between critical care physician management and patient mortality in the intensive care unit. Ann Intern Med 2008; 148:801–809.
- Kim MM, Barnato AE, Angus DC, Fleisher LA, Kahn JM. The effect of multidisciplinary care teams on intensive care unit mortality. Arch Intern Med 2010; 170:369–376.
- Carson SS, Stocking C, Podsadecki T, et al. Effects of organizational change in the medical intensive care unit of a teaching hospital: a comparison of ‘open’ and ‘closed’ formats. JAMA 1996; 276:322–328.
- Treggiari MM, Martin DP, Yanez ND, Caldwell E, Hudson LD, Rubenfeld GD. Effect of intensive care unit organizational model and structure on outcomes in patients with acute lung injury. Am J Respir Crit Care Med 2007; 176:685–690.
- Angus DC, Kelley MA, Schmitz RJ, White A, Popovich J; Committee on Manpower for Pulmonary and Critical Care Societies (COMPACCS). Caring for the critically ill patient. Current and projected workforce requirements for care of the critically ill and patients with pulmonary disease: can we meet the requirements of an aging population? JAMA 2000; 284:2762–2770.
- Boutros AR. Anesthesiology and intensive care (editorial). Anesthesiology 1974; 41:319–320.
- Boyle WA. A critical time for anesthesiology? American Society of Anesthesiologists (ASA) Newsletter, September 2009;10–11. http://viewer.zmags.com/publication/9960917c#/9960917c/12. Accessed July 13, 2011.
- Ewart GW, Marcus L, Gaba MM, Bradner RH, Medina JL, Chandler EB. The critical care medicine crisis: a call for federal action: a white paper from the critical care professional societies. Chest 2004; 125:1518–1521.
- Kaplan LJ, Shaw AD. Standards for education and credentialing in critical care medicine. JAMA 2011; 305:296–297.
- Leong JR, Sirio CA, Rotondi AJ. eICU program favorably affects clinical and economic outcomes. Crit Care 2005, http://ccforum.com/content/9/5/E22. Accessed July 13, 2011.
- Bloomfield EL. The impact of economics on changing medical technology with reference to critical care medicine in the United States. Anesth Analg 2003; 96:418–425.
- Gajic O, Afessa B. Physician staffing models and patient safety in the ICU. Chest 2009; 135:1038–1044.
- Baggs JG, Schmitt MH, Mushlin AI, et al. Association between nurse-physician collaboration and patient outcomes in three intensive care units. Crit Care Med 1999; 27:1991–1998.
- Hanson CW, Deutschman CS, Anderson HL, et al. Effects of an organized critical care service on outcomes and resource utilization: a cohort study. Crit Care Med 1999; 27:270–274.
- Pronovost PJ, Angus DC, Dorman T, Robinson KA, Dremsizov TT, Young TL. Physician staffing patterns and clinical outcomes in critically ill patients: a systematic review. JAMA 2002; 288:2151–2162.
- Levy MM, Rapoport J, Lemeshow S, Chalfin DB, Phillips G, Danis M. Association between critical care physician management and patient mortality in the intensive care unit. Ann Intern Med 2008; 148:801–809.
- Kim MM, Barnato AE, Angus DC, Fleisher LA, Kahn JM. The effect of multidisciplinary care teams on intensive care unit mortality. Arch Intern Med 2010; 170:369–376.
- Carson SS, Stocking C, Podsadecki T, et al. Effects of organizational change in the medical intensive care unit of a teaching hospital: a comparison of ‘open’ and ‘closed’ formats. JAMA 1996; 276:322–328.
- Treggiari MM, Martin DP, Yanez ND, Caldwell E, Hudson LD, Rubenfeld GD. Effect of intensive care unit organizational model and structure on outcomes in patients with acute lung injury. Am J Respir Crit Care Med 2007; 176:685–690.
- Angus DC, Kelley MA, Schmitz RJ, White A, Popovich J; Committee on Manpower for Pulmonary and Critical Care Societies (COMPACCS). Caring for the critically ill patient. Current and projected workforce requirements for care of the critically ill and patients with pulmonary disease: can we meet the requirements of an aging population? JAMA 2000; 284:2762–2770.
- Boutros AR. Anesthesiology and intensive care (editorial). Anesthesiology 1974; 41:319–320.
- Boyle WA. A critical time for anesthesiology? American Society of Anesthesiologists (ASA) Newsletter, September 2009;10–11. http://viewer.zmags.com/publication/9960917c#/9960917c/12. Accessed July 13, 2011.
- Ewart GW, Marcus L, Gaba MM, Bradner RH, Medina JL, Chandler EB. The critical care medicine crisis: a call for federal action: a white paper from the critical care professional societies. Chest 2004; 125:1518–1521.
- Kaplan LJ, Shaw AD. Standards for education and credentialing in critical care medicine. JAMA 2011; 305:296–297.
- Leong JR, Sirio CA, Rotondi AJ. eICU program favorably affects clinical and economic outcomes. Crit Care 2005, http://ccforum.com/content/9/5/E22. Accessed July 13, 2011.
Jet lag and shift work sleep disorders: How to help reset the internal clock
For people who must travel long distances east or west by air or who must work the night shift, some relief is possible for the grogginess and disorientation that often ensue. The problems arise from the body’s internal clock being out of sync with the sun. Part of the solution involves helping reset the internal clock, or sometimes, preventing it from resetting itself.
This review will focus on jet lag sleep disorder and shift work sleep disorder, with an emphasis on the causes, the clinical assessment, and evidence-based treatment options.
WHEN THE INTERNAL CLOCK IS OUT OF SYNC WITH THE SUN
Circadian rhythm sleep disorders are the result of dyssynchrony between the body’s internal clock and the external 24-hour light-dark cycle. Patients typically present with insomnia or excessive somnolence. These disorders may represent an intrinsic disorder, such as delayed or advanced sleep-phase disorder, or may be the result of transmeridian air travel or working nonstandard shifts.1
The intrinsic human circadian period is typically slightly longer than 24 hours,9 but it is synchronized (“entrained”) to the 24-hour day by various environmental inputs, or zeitgebers (German for “time-givers”), the most important of which is light exposure.10
When the internal clock is out of sync with the sun, the misalignment can result in daytime anergia, alternating complaints of insomnia and hypersomnia, and various other symptoms, including emotional disturbances and gastrointestinal distress. In particular, long-distance air travel or a nocturnal work schedule overwhelms the ability of the intrinsic clock to adjust rapidly enough, and the result is jet lag sleep disorder or shift work sleep disorder.1
TOOLS TO EVALUATE CIRCADIAN RHYTHM DISTURBANCES
A thorough history is the cornerstone of the evaluation for all sleep disorders, and if a circadian rhythm disturbance is suspected, the sleep history is supplemented with specific questions to establish a clear diagnosis.
When assessing for jet lag disorder, ask about:
- The patient’s degree of sleep deprivation before and during travel
- His or her innate circadian preference (ie, whether he or she is a “night owl” or “early bird”)
- Patterns of alcohol and caffeine consumption.
When assessing for shift work disorder, include the above questions and also look for differences in the sleep-wake schedule on working days vs nonworking days, as well as external contributors to poor sleep quality (eg, the degree to which daytime sleep is not “protected”).
The following tools help in acquiring this information.
Sleep diary
In a sleep diary or log, patients record the times that they take naps, maintain consolidated sleep, and subsequently arise. The diary also prompts the patient for information about sleep latency, wakefulness after sleep onset, time in bed, medication and caffeine intake, and the restorative quality of sleep.
While the sleep diary by itself may provide insight into counteractive sleep-related behaviors and misperceptions the patient may have, compliance is often limited. Therefore, the sleep diary is best used in conjunction with actigraphy.
Actigraphy
An actigraph is a wristwatch-size motion detector, typically worn continuously for 7 days or longer. The data it gathers and stores serve as a surrogate measure of various sleep-wake variables.11
Either a sleep diary or actigraphy is required to demonstrate the stability of sleep patterns and circadian preference, but the actigraph typically generates more reliable data.11,12 It is also valuable in assessing the response to treatment of circadian rhythm sleep disorders.13
Are you an early bird or a night owl?
The Morningness-Eveningness questionnaire contains 19 items. Night owls tend to score lower on it than early birds do.14 This information may help some people avoid situations in which they may not do well, such as an early bird going on a permanent night-shift schedule.
Other assessment tools
Polysomnography is used primarily to rule out sleep-disordered breathing; it is not indicated for routine evaluation of circadian rhythm sleep disorders.
The minimum core body temperature and the peak melatonin secretion follow a 24-hour cycle. Although these measures are often used in research, they are not routinely used in clinical practice. (The minimum core body temperature is discussed further below.)
JET LAG SLEEP DISORDER
Jet lag results from air travel across multiple time zones, with a resultant discordance between the internal circadian clock and the destination’s light-dark cycle. Most sufferers report sleeping poorly at night and feeling groggy during the day, and some also experience general malaise and gastrointestinal distress.1
The severity depends on a number of variables.
Going west is easier than going east
Westward travel is normally less taxing than eastward travel, as it requires setting one’s internal clock later rather than earlier. Presumably, because the circadian period tends to exceed 24 hours, we can move our internal clock later by about 2 hours per day, but we can move it earlier by only 1 to 1.5 hours.15,16
The more time zones crossed, the longer it takes the circadian pacemaker to re-entrain and the longer-lasting and more severe are the symptoms of jet lag. Travel across one or two time zones is only transiently troublesome.
Does age affect jet lag?
Whether age affects the severity of jet lag is not yet known.
In a study of simulated jet lag (requiring a 6-hour advance), middle-aged people (ages 37 to 52) experienced a greater degree of fragmented sleep on polysomnography than younger ones (ages 18 to 25). The older group also had greater impairment in daytime alertness, suggesting that phase tolerance—ie, the ability to sleep at an abnormal time in the circadian cycle17—decreases with age. However, two field studies involving both eastward and westward travel yielded the opposite results, suggesting that older age may actually protect against jet lag.18–20
Methodologic differences preclude direct comparisons of the studies, as do differences in the age groups studied.
Light exposure can help or hurt, depending on the timing
Our core body temperature dips to its lowest point about 2 to 3 hours before we habitually awake. Exposure to bright light in the hours leading up to this minimum (the inverted triangle in Figure 2) sets our internal clock later (a phase delay)—desirable, say, for someone travelling from New York City to Los Angeles. Conversely, exposure to bright light after this temperature minimum sets the clock earlier.
Inadvertent shifting of circadian phase in the wrong direction (“antidromic re-entrainment”) is common and delays circadian reacclimation and the dissipation of jet lag symptoms.
We discuss ways to reduce antidromic reentrainment in more detail further below.
Other factors
Other factors that contribute to travel fatigue include sleep deprivation (before the flight or en route), acute discomfort as the plane ascends to its cruising altitude,25 and excessive alcohol or caffeine intake during the flight. Although the effects of these factors rapidly diminish once one reaches the travel destination, jet lag will persist until circadian re-entrainment occurs.15
NONDRUG THERAPIES FOR JET LAG SLEEP DISORDER
The goal of treatment is to realign the circadian rhythm in the most rapid and efficient way and to minimize symptoms in the meantime. Frequent shifts to different time zones, often required in business travel, are very difficult to accommodate, and business travelers actually may do better if they remain on their home-based schedule.
One study compared keeping home-based sleep hours as opposed to adopting local sleep hours during a 2-day stay after a 9-hour westward flight.26 Travelers who remained on home-based hours were less sleepy and had lower (ie, better) global jet lag ratings than those who adopted local sleep hours, in part because of better sleep quality and duration. Nevertheless, about one-third of the participants said they preferred to adhere to the local schedule.
Strategic avoidance of, and exposure to, light
If the traveler intends to remain at the destination long enough, he or she can adjust better (and avoid an antidromic process) via strategic avoidance of and exposure to light.24
People travelling east, who want to set their clocks ahead (a phase advance), need to keep to the dark in the 3 hours leading up to the time they reach their minimum core body temperature (depicted as “D” in Figure 3), and then expose themselves to light in the 3 hours immediately after (“L” in Figure 3). Thus, the traveler from Chicago to Paris would do better by avoiding light exposure on arrival, either by remaining in darkness in his or her hotel room, or by wearing dark sunglasses when outdoors. Wearing sunglasses during transit to the hotel would also help avoid light exposure.
When attempting to delay circadian rhythms, the opposite light-dark patterns are sought, as depicted in Figure 4. As flight and layover patterns often do not permit strict adherence to these measures, they represent idealized scenarios.
The first step is to make a grid with a concurrent listing of home and destination times. In the example in Figure 3, the person is traveling seven time zones east. On day 0, a rectangle is drawn around the times representing home-based sleep hours.
Next, we mark the time at which we expect the traveler’s core body temperature to reach its minimum (inverted triangle). If the person habitually sleeps no more than 7 hours per night, then we mark this point as 2 hours before his or her habitual wake-up time; if the person sleeps more than 7 hours, then we place it 3 hours before wake-up time.23,29 This process is repeated at the bottom of the grid to represent the desired sleep schedule at the traveler’s destination. The distance between the home and the destination-based minimum core body temperature symbols represents the required degree of circadian realignment.
If a phase advance is required (eg, if travelling from Chicago to Paris), the core body temperature symbol is drawn on day 1 in the same location as day 0. For each subsequent day, the symbol is moved 1 hour earlier (which is about how fast the internal clock can advance),15,27 until a clock time within 1 hour of the desired destination core body temperature time is reached or satisfactory sleep and daytime functioning are achieved (Figure 3). If a phase delay is required (eg, if travelling from New York City to Los Angeles), the symbol is drawn 2 hours later on day 1 than on day 0 (reflecting the greater ease at which delays are achieved),15,27 with subsequent daily shifts in 2-hour increments, again until a clock time within 1 hour of the desired destination minimum core body temperature time is reached or satisfactory sleep and daytime functioning are achieved.
Requirements for darkness can be met with protective eyewear (ie, dark sunglasses), or by remaining in a dark room. Light requirements can be met with outdoor exposure, with a commercial light box, or with a separate apparatus (eg, goggles, visors) portable enough for travel.
DRUGS TO TREAT JET LAG SLEEP DISORDER
Melatonin appears safe
Most field studies have found that nightly doses of melatonin (2–8 mg) improve the quality of sleep30–32 or alleviate daytime symptoms of jet lag, or both.20,30,31,33–36 Immediate-release preparations appear to be more effective than slow-release ones.31 Although most studies looked exclusively at adaptation to eastward travel,30–32,35,36 one studied westward travel,33 and another assessed melatonin’s effects during both departure and return trips that traversed 11 time zones.34
In studies of preflight dosing, melatonin was scheduled for up to 3 days before departure (and en route in two instances),30,34 at clock hours corresponding to the nocturnal sleep period at the travel destination (consistent times daily), and then for a subsequent 3 to 4 days between a destination time of 22:00 and 00:00 hours (ie, at bedtime).30,31,34–36 Several other studies further simplified this regimen, with participants taking nocturnal melatonin only on arrival at the destination, either for eastward31,32 or for westward travel.33
The study involving solely westward travel (Los Angeles to New Zealand) was the only one of the studies with positive findings that allowed for comparisons between participants who received melatonin before departure (3 days at 5-mg doses, taken between 07:00 and 08:00 Los Angeles time) and continuing for 5 days after arrival at 22:00 to 00:00 New Zealand time, and those who received melatonin beginning only on arrival.33 Significantly better jet lag outcomes were found in the latter group.
An important caveat is that melatonin is sold over the counter as a nutritional supplement and is not regulated by the United States Food and Drug Administration (FDA), so verification of purity of the product is difficult.
A comprehensive review by the National Academy of Sciences stated that, given the available data, short-term use of melatonin in total daily doses of 10 mg or less in healthy adults appears to be safe.37
Benzodiazepine receptor agonists improve sleep, but maybe not sleepiness
The use of standard hypnotics during periods of circadian realignment appears to be commonplace but has not been well studied.20 Trials of the newer benzodiazepine receptor agonists—three studies of zolpidem (Ambien) 10 mg30,38,39 and two of zopiclone 5 to 7.5 mg32,40—found consistently favorable subjective30,38 and objective32,39,40 outcomes in counteracting jet-lag-induced insomnia (for both eastward and westward travel). (Note: Zopiclone is not available in the United States, but its enantiomer eszopiclone [Lunesta] is.) However, the evidence is less clear for daytime symptoms of jet lag, with outcomes reported as favorable,30 equivocal,40 or inaccessible.32,38,39
The discrepancy between studies incorporating systematic daytime assessments may be due to differential medication effects (zolpidem vs zopiclone).
In two studies that compared these standard hypnotics to oral melatonin, one found that zopiclone 5 mg and melatonin 2 mg were equally beneficial with respect to sleep variables (other jet lag symptoms were not assessed).32 In another study, zolpidem 10 mg was superior to melatonin 5 mg for sleep and other jet lag symptoms, and the combination of zolpidem and melatonin was no better than zolpidem alone.30
Importantly, however, adverse effects were more frequent in those taking zolpidem and included nausea, vomiting, and confusion.30 Although these effects were not deemed serious, 14 participants (10%) withdrew from the study.
Stimulants
Caffeine is commonly used to combat the sleepiness of jet lag, but only two controlled field studies have assessed its efficacy.41,42 Both used slow-release preparations at a daily dosage of 300 mg.
In one study, after an eastward flight traversing seven time zones, participants took the pill at 08:00 destination time every day for 5 days.41 Curiously, alertness and other jet lag symptoms were not assessed, but circadian rhythms (determined by levels of cortisol in saliva) were re-entrained at a more rapid rate with caffeine than with placebo, and to a degree comparable with that achieved by exogenous melatonin.
In a follow-up study by the same group, those receiving caffeine were objectively less sleepy (as assessed by multiple sleep latency tests) than those taking melatonin or placebo, but subjective differences between groups were not identified.42 Furthermore, those taking caffeine had significantly more nocturnal sleep complaints, as assessed both objectively and subjectively.
A recent randomized, double-blind, placebo-controlled trial of the stimulant armodafinil (Nuvigil) found less sleepiness on multiple sleep latency testing and a decrease in jet leg symptoms with a dosage of 150 mg than with placebo.43
SHIFT WORK SLEEP DISORDER: DEFINITION, PREDISPOSING FACTORS
Shift work refers to nonstandard work schedules, including on-call duty, rotating shifts, and permanent night work. In the United States, one in five workers works a nonstandard shift.20
While shift work presents obvious difficulties, the diagnosis of shift work sleep disorder is reserved for those who have chronic insomnia or sleepiness at times that are not conducive to the externally demanded sleep-wake schedule, despite having the opportunity for sufficient daytime sleep.1 When defined in such a fashion, this disorder may afflict nearly a third of workers,44 with potential adverse effects on safety, health, and quality of life.
Older age is considered a risk factor for intolerance to shift work.20 In a study of physiologic phase shifts in response to night work, older workers were less able to recover after several night shifts.45 A large survey of police officers working the night shift supported the finding of more sleep disruption and on-duty sleepiness in older people.46
TREATMENT OF SHIFT WORK SLEEP DISORDER
Bright light at work, sunglasses on the way home
Various field studies have described hastening of circadian adaptation (and immediate alerting effects) during night shifts with the use of bright light.20
Boivin and James47 found that workers who received 6 hours of intermittent bright light during their shifts experienced significantly greater phase delays than those who received no such intervention. Those receiving bright light also wore sunglasses during the commute home (to protect from an undesired phase advance), and this has demonstrated favorable effects as an independent intervention.48
Drug treatment of shift work sleep disorder
Melatonin: Mixed results. Two field studies found that taking melatonin (5–6 mg) before the daytime sleep period had a favorable impact on subjective sleep quality.49,50 However, two other studies found no such benefit with doses ranging from 6 to 10 mg.51,52 Differences between these studies—eg, shift schedules, dosages, and the time the melatonin was taken—preclude definitive comparisons.
Effects of melatonin on workplace alertness are indeterminate because of inconsistent measurements of this variable. Importantly, a simulated shift work study found no phase-shifting advantages of melatonin in those who concomitantly used bright light during their work shift with or without morning protective eyewear.48
Hypnotic drugs. In simulation studies and field studies, people taking benzodiazepine receptor agonists have consistently said they sleep better.53–58 A simulation study noted additional benefit in the ability to stay alert during the night shift (assessed by maintenance of wakefulness testing),55 but two other studies saw no changes in manifest sleepiness (assessed with multiple sleep latency tests).53,54 These divergent findings may represent different effects on these two dimensions of sleepiness.
The only field study to assess post-sleep psychomotor performance found no impairments after taking 7.5 mg of zopiclone, a relatively long-acting nonbenzodiazepine hypnotic.57
Stimulants. In the largest trial to date of shift work sleep disorder, modafinil 200 mg (the only drug currently FDA-approved for shift work sleep disorder) had significant benefits compared with placebo with respect to objective measurements of workplace sleepiness, reaction time performance testing, and self-rated improvement of symptoms.59 Perhaps because of the low dose studied, both treated and untreated patients continued to manifest sleepiness within the pathologic range on objective testing.
Although the efficacy of caffeine is well documented as a countermeasure for sleepiness during experimentally induced sleep deprivation,20 very few field trials have specifically addressed impairments associated with shift work sleep disorder. In one study, caffeine at a dose of 4 mg/kg taken 30 minutes before starting a night shift provided objective improvement in both performance and alertness.60
Strategic napping is an additional practical intervention to promote alertness during night shifts, and cumulative data indicate that it provides objective and subjective improvements in alertness and performance.61,62 Earlier timed naps (ie, before or during the early portion of a shift) of short duration (ie, 20 minutes or less) are likely to produce maximal benefit, because they avoid sleep inertia (the grogginess or sleepiness that may follow a long nap), and also because they have no effect on the subsequent daytime sleep bout.61,63
Interventions may also be used in combination. For example, napping in conjunction with caffeine results in a greater degree of increased objective alertness than either intervention alone.60
How about days off?
The recommendations described here presume that shift workers maintain the workday sleep-wake schedule continuously, including when they are not at work. This is likely not a real-world scenario.
Smith et al64 developed a “compromise” phase position, whereby internal rhythms are optimized to facilitate alertness during work and sleepiness during the day, while allowing one to adopt a non-workday sleep schedule that maintains accessibility to family and social activities. In brief, non-workday sleep starts about 5.5 hours earlier than workday sleep; all sleep bouts are followed by brief exposure to bright light (to avoid excessive phase delay); and, as described previously, both workplace bright light and protection from morning light are implemented.
Although further studies are needed to determine whether this regimen is practical in real life, study participants who achieved desired partial phase shifts had performance ratings on a par with baseline levels, and comparable to those in a group that achieved complete re-entrainment.64
Finally, all shift workers need to be encouraged to protect the daytime bedroom environment just as daytime workers protect their nighttime environment. Sleep should be sought in an appropriately darkened and quiet environment, phones and doorbells silenced, and appointments scheduled accordingly.
- International Classification of Sleep Disorders: Diagnostic and Coding Manual/American Academy of Sleep Medicine. 2nd ed. Westchester, IL: American Academy of Sleep Medicine; 2005.
- Borbély AA, Achermann P. Concepts and models of sleep regulation: an overview. J Sleep Res 1992; 1:63–79.
- Carskadon MA, Dement WC. Effects of total sleep loss on sleep tendency. Percept Mot Skills 1979; 48:495–506.
- Beersma DG, Gordijn MC. Circadian control of the sleep-wake cycle. Physiol Behav 2007; 90:190–195.
- Moore RY, Eichler VB. Loss of a circadian adrenal corticosterone rhythm following suprachiasmatic lesions in the rat. Brain Res 1972; 42:201–206.
- Stephan FK, Zucker I. Circadian rhythms in drinking behavior and locomotor activity of rats are eliminated by hypothalamic lesions. Proc Natl Acad Sci U S A 1972; 69:1583–1586.
- Welsh DK, Logothetis DE, Meister M, Reppert SM. Individual neurons dissociated from rat suprachiasmatic nucleus express independently phased circadian firing rhythms. Neuron 1995; 14:697–706.
- Ralph MR, Foster RG, Davis FC, Menaker M. Transplanted suprachiasmatic nucleus determines circadian period. Science 1990; 247:975–978.
- Czeisler CA, Duffy JF, Shanahan TL, et al. Stability, precision, and near-24-hour period of the human circadian pacemaker. Science 1999; 284:2177–2181.
- Waterhouse JM, DeCoursey PJ. Human circadian organization. In:Dunlap JC, Loros JJ, DeCoursey PJ, editors. Chronobiology: Biological Timekeeping. Sunderland, MA: Sinauer Associates; 2004:291–324.
- Morgenthaler T, Alessi C, Friedman L, et al; Standards of Practice Committee; American Academy of Sleep Medicine. Practice parameters for the use of actigraphy in the assessment of sleep and sleep disorders: an update for 2007. Sleep 2007; 30:519–529.
- Bradshaw DA, Yanagi MA, Pak ES, Peery TS, Ruff GA. Nightly sleep duration in the 2-week period preceding multiple sleep latency testing. J Clin Sleep Med 2007; 3:613–619.
- Morgenthaler TI, Lee-Chiong T, Alessi C, et al; Standards of Practice Committee of the American Academy of Sleep Medicine. Practice parameters for the clinical evaluation and treatment of circadian rhythm sleep disorders. An American Academy of Sleep Medicine report. Sleep 2007; 30:1445–1459.
- Horne JA, Ostberg O. A self-assessment questionnaire to determine morningness-eveningness in human circadian rhythms. Int J Chronobiol 1976; 4:97–110.
- Waterhouse J, Reilly T, Atkinson G, Edwards B. Jet lag: trends and coping strategies. Lancet 2007; 369:1117–1129.
- Eastman CI, Gazda CJ, Burgess HJ, Crowley SJ, Fogg LF. Advancing circadian rhythms before eastward flight: a strategy to prevent or reduce jet lag. Sleep 2005; 28:33–44.
- Moline ML, Pollak CP, Monk TH, et al. Age-related differences in recovery from simulated jet lag. Sleep 1992; 15:28–40.
- Waterhouse J, Edwards B, Nevill A, et al. Identifying some determinants of “jet lag” and its symptoms: a study of athletes and other travellers. Br J Sports Med 2002; 36:54–60.
- Tresguerres JA, Ariznavarreta C, Granados B, et al. Circadian urinary 6-sulphatoxymelatonin, cortisol excretion and locomotor activity in airline pilots during transmeridian flights. J Pineal Res 2001; 31:16–22.
- Sack RL, Auckley D, Auger RR, et al; American Academy of Sleep Medicine. Circadian rhythm sleep disorders: part I, basic principles, shift work and jet lag disorders. An American Academy of Sleep Medicine review. Sleep 2007; 30:1460–1483.
- Burgess HJ, Sharkey KM, Eastman CI. Bright light, dark and melatonin can promote circadian adaptation in night shift workers. Sleep Med Rev 2002; 6:407–420.
- Lewy AJ, Bauer VK, Saeeduddin A, et al. The human phase response curve (PRC) to melatonin is about 12 hours out of phase with the PRC to light. Chronobiol Int 1998; 15:71–83.
- Burgess HJ, Eastman CT. Prevention of Jet Lag. 2010. http://pier.acponline.org/physicians/screening/prev1015/prev1015.html. Accessed June 25, 2010.
- Daan S, Lewy AJ. Scheduled exposure to daylight: a potential strategy to reduce “jet lag” following transmeridian flight. Psychopharmacol Bull 1984; 20:566–568.
- Muhm JM, Rock PB, McMullin DL, et al. Effect of aircraft-cabin altitude on passenger discomfort. N Engl J Med 2007; 357:18–27.
- Lowden A, Akerstedt T. Retaining home-base sleep hours to prevent jet lag in connection with a westward flight across nine time zones. Chronobiol Int 1998; 15:365–376.
- Eastman CI, Burgess HJ. How to travel the world without jet lag. Sleep Med Clin 2009; 4:241–255.
- Revell VL, Eastman CI. How to trick mother nature into letting you fly around or stay up all night. J Biol Rhythms 2005; 20:353–365.
- Cagnacci A, Elliott JA, Yen SS. Melatonin: a major regulator of the circadian rhythm of core temperature in humans. J Clin Endocrinol Metab 1992; 75:447–452.
- Suhner A, Schlagenhauf P, Höfer I, Johnson R, Tschopp A, Steffen R. Effectiveness and tolerability of melatonin and zolpidem for the alleviation of jet lag. Aviat Space Environ Med 2001; 72:638–646.
- Suhner A, Schlagenhauf P, Johnson R, Tschopp A, Steffen R. Comparative study to determine the optimal melatonin dosage form for the alleviation of jet lag. Chronobiol Int 1998; 15:655–666.
- Paul MA, Gray G, Sardana TM, Pigeau RA. Melatonin and zopiclone as facilitators of early circadian sleep in operational air transport crews. Aviat Space Environ Med 2004; 75:439–443.
- Petrie K, Dawson AG, Thompson L, Brook R. A double-blind trial of melatonin as a treatment for jet lag in international cabin crew. Biol Psychiatry 1993; 33:526–530.
- Petrie K, Conaglen JV, Thompson L, Chamberlain K. Effect of melatonin on jet lag after long haul flights. BMJ 1989; 298:705–707.
- Arendt J, Aldhous M, Marks V. Alleviation of jet lag by melatonin: preliminary results of controlled double blind trial. Br Med J (Clin Res Ed) 1986; 292:1170.
- Claustrat B, Brun J, David M, Sassolas G, Chazot G. Melatonin and jet lag: confirmatory result using a simplified protocol. Biol Psychiatry 1992; 32:705–711.
- Committee on the Framework for Evaluating the Safety of Dietary Supplements, Food and Nutrition Board, Board on Life Sciences, Institute of Medicine and National Research Council of the National Academies. Dietary supplements: a framework for evaluating safety. Washington, DC: The National Academies Press; 2005.
- Jamieson AO, Zammit GK, Rosenberg RS, Davis JR, Walsh JK. Zolpidem reduces the sleep disturbance of jet lag. Sleep Med 2001; 2:423–430.
- Hirschfeld U, Moreno-Reyes R, Akseki E, et al. Progressive elevation of plasma thyrotropin during adaptation to simulated jet lag: effects of treatment with bright light or zolpidem. J Clin Endocrinol Metab 1996; 81:3270–3277.
- Daurat A, Benoit O, Buguet A. Effects of zopiclone on the rest/activity rhythm after a westward flight across five time zones. Psychopharmacology (Berl) 2000; 149:241–245.
- Piérard C, Beaumont M, Enslen M, et al. Resynchronization of hormonal rhythms after an eastbound flight in humans: effects of slow-release caffeine and melatonin. Eur J Appl Physiol 2001; 85:144–150.
- Beaumont M, Batéjat D, Piérard C, et al. Caffeine or melatonin effects on sleep and sleepiness after rapid eastward transmeridian travel. J Appl Physiol 2004; 96:50–58.
- Rosenberg RP, Bogan RK, Tiller JM, et al. A phase 3, double-blind, randomized, placebo-controlled study of armodafinil for excessive sleepiness associated with jet lag disorder. Mayo Clin Proc 2010; 85:630–638.
- Drake CL, Roehrs T, Richardson G, Walsh JK, Roth T. Shift work sleep disorder: prevalence and consequences beyond that of symptomatic day workers. Sleep 2004; 27:1453–1462.
- Härmä MI, Hakola T, Akerstedt T, Laitinen JT. Age and adjustment to night work. Occup Environ Med 1994; 51:568–573.
- Smith L, Mason C. Reducing night shift exposure: a pilot study of rota, night shift and age effects on sleepiness and fatigue. J Hum Ergol (Tokyo) 2001; 30:83–87.
- Boivin DB, James FO. Circadian adaptation to night-shift work by judicious light and darkness exposure. J Biol Rhythms 2002; 17:556–567.
- Crowley SJ, Lee C, Tseng CY, Fogg LF, Eastman CI. Combinations of bright light, scheduled dark, sunglasses, and melatonin to facilitate circadian entrainment to night shift work. J Biol Rhythms 2003; 18:513–523.
- Folkard S, Arendt J, Clark M. Can melatonin improve shift workers’ tolerance of the night shift? Some preliminary findings. Chronobiol Int 1993; 10:315–320.
- Yoon IY, Song BG. Role of morning melatonin administration and attenuation of sunlight exposure in improving adaptation of nightshift workers. Chronobiol Int 2002; 19:903–913.
- James M, Tremea MO, Jones JS, Krohmer JR. Can melatonin improve adaptation to night shift? Am J Emerg Med 1998; 16:367–370.
- Jorgensen KM, Witting MD. Does exogenous melatonin improve day sleep or night alertness in emergency physicians working night shifts? Ann Emerg Med 1998; 31:699–704.
- Walsh JK, Schweitzer PK, Anch AM, Muehlbach MJ, Jenkins NA, Dickins QS. Sleepiness/alertness on a simulated night shift following sleep at home with triazolam. Sleep 1991; 14:140–146.
- Walsh JK, Sugerman JL, Muehlbach MJ, Schweitzer PK. Physiological sleep tendency on a simulated night shift: adaptation and effects of triazolam. Sleep 1988; 11:251–264.
- Porcù S, Bellatreccia A, Ferrara M, Casagrande M. Performance, ability to stay awake, and tendency to fall asleep during the night after a diurnal sleep with temazepam or placebo. Sleep 1997; 20:535–541.
- Monchesky TC, Billings BJ, Phillips R, Bourgouin J. Zopiclone in insomniac shiftworkers. Evaluation of its hypnotic properties and its effects on mood and work performance. Int Arch Occup Environ Health 1989; 61:255–259.
- Moon CA, Hindmarch I, Holland RL. The effect of zopiclone 7.5 mg on the sleep, mood and performance of shift workers. Int Clin Psychopharmacol 1990; 5(suppl 2):79–83.
- Puca FM, Perrucci S, Prudenzano MP, et al. Quality of life in shift work syndrome. Funct Neurol 1996; 11:261–268.
- Czeisler CA, Walsh JK, Roth T, et al; US Modafinil in Shift Work Sleep Disorder Study Group. Modafinil for excessive sleepiness associated with shift-work sleep disorder. N Engl J Med 2005; 353:476–486.
- Schweitzer PK, Randazzo AC, Stone K, Erman M, Walsh JK. Laboratory and field studies of naps and caffeine as practical countermeasures for sleep-wake problems associated with night work. Sleep 2006; 29:39–50.
- Sallinen M, Härmä M, Akerstedt T, Rosa R, Lillqvist O. Promoting alertness with a short nap during a night shift. J Sleep Res 1998; 7:240–247.
- Garbarino S, Mascialino B, Penco MA, et al. Professional shift-work drivers who adopt prophylactic naps can reduce the risk of car accidents during night work. Sleep 2004; 27:1295–1302.
- Purnell MT, Feyer AM, Herbison GP. The impact of a nap opportunity during the night shift on the performance and alertness of 12-h shift workers. J Sleep Res 2002; 11:219–227.
- Smith MR, Fogg LF, Eastman CI. A compromise circadian phase position for permanent night work improves mood, fatigue, and performance. Sleep 2009; 32:1481–1489.
For people who must travel long distances east or west by air or who must work the night shift, some relief is possible for the grogginess and disorientation that often ensue. The problems arise from the body’s internal clock being out of sync with the sun. Part of the solution involves helping reset the internal clock, or sometimes, preventing it from resetting itself.
This review will focus on jet lag sleep disorder and shift work sleep disorder, with an emphasis on the causes, the clinical assessment, and evidence-based treatment options.
WHEN THE INTERNAL CLOCK IS OUT OF SYNC WITH THE SUN
Circadian rhythm sleep disorders are the result of dyssynchrony between the body’s internal clock and the external 24-hour light-dark cycle. Patients typically present with insomnia or excessive somnolence. These disorders may represent an intrinsic disorder, such as delayed or advanced sleep-phase disorder, or may be the result of transmeridian air travel or working nonstandard shifts.1
The intrinsic human circadian period is typically slightly longer than 24 hours,9 but it is synchronized (“entrained”) to the 24-hour day by various environmental inputs, or zeitgebers (German for “time-givers”), the most important of which is light exposure.10
When the internal clock is out of sync with the sun, the misalignment can result in daytime anergia, alternating complaints of insomnia and hypersomnia, and various other symptoms, including emotional disturbances and gastrointestinal distress. In particular, long-distance air travel or a nocturnal work schedule overwhelms the ability of the intrinsic clock to adjust rapidly enough, and the result is jet lag sleep disorder or shift work sleep disorder.1
TOOLS TO EVALUATE CIRCADIAN RHYTHM DISTURBANCES
A thorough history is the cornerstone of the evaluation for all sleep disorders, and if a circadian rhythm disturbance is suspected, the sleep history is supplemented with specific questions to establish a clear diagnosis.
When assessing for jet lag disorder, ask about:
- The patient’s degree of sleep deprivation before and during travel
- His or her innate circadian preference (ie, whether he or she is a “night owl” or “early bird”)
- Patterns of alcohol and caffeine consumption.
When assessing for shift work disorder, include the above questions and also look for differences in the sleep-wake schedule on working days vs nonworking days, as well as external contributors to poor sleep quality (eg, the degree to which daytime sleep is not “protected”).
The following tools help in acquiring this information.
Sleep diary
In a sleep diary or log, patients record the times that they take naps, maintain consolidated sleep, and subsequently arise. The diary also prompts the patient for information about sleep latency, wakefulness after sleep onset, time in bed, medication and caffeine intake, and the restorative quality of sleep.
While the sleep diary by itself may provide insight into counteractive sleep-related behaviors and misperceptions the patient may have, compliance is often limited. Therefore, the sleep diary is best used in conjunction with actigraphy.
Actigraphy
An actigraph is a wristwatch-size motion detector, typically worn continuously for 7 days or longer. The data it gathers and stores serve as a surrogate measure of various sleep-wake variables.11
Either a sleep diary or actigraphy is required to demonstrate the stability of sleep patterns and circadian preference, but the actigraph typically generates more reliable data.11,12 It is also valuable in assessing the response to treatment of circadian rhythm sleep disorders.13
Are you an early bird or a night owl?
The Morningness-Eveningness questionnaire contains 19 items. Night owls tend to score lower on it than early birds do.14 This information may help some people avoid situations in which they may not do well, such as an early bird going on a permanent night-shift schedule.
Other assessment tools
Polysomnography is used primarily to rule out sleep-disordered breathing; it is not indicated for routine evaluation of circadian rhythm sleep disorders.
The minimum core body temperature and the peak melatonin secretion follow a 24-hour cycle. Although these measures are often used in research, they are not routinely used in clinical practice. (The minimum core body temperature is discussed further below.)
JET LAG SLEEP DISORDER
Jet lag results from air travel across multiple time zones, with a resultant discordance between the internal circadian clock and the destination’s light-dark cycle. Most sufferers report sleeping poorly at night and feeling groggy during the day, and some also experience general malaise and gastrointestinal distress.1
The severity depends on a number of variables.
Going west is easier than going east
Westward travel is normally less taxing than eastward travel, as it requires setting one’s internal clock later rather than earlier. Presumably, because the circadian period tends to exceed 24 hours, we can move our internal clock later by about 2 hours per day, but we can move it earlier by only 1 to 1.5 hours.15,16
The more time zones crossed, the longer it takes the circadian pacemaker to re-entrain and the longer-lasting and more severe are the symptoms of jet lag. Travel across one or two time zones is only transiently troublesome.
Does age affect jet lag?
Whether age affects the severity of jet lag is not yet known.
In a study of simulated jet lag (requiring a 6-hour advance), middle-aged people (ages 37 to 52) experienced a greater degree of fragmented sleep on polysomnography than younger ones (ages 18 to 25). The older group also had greater impairment in daytime alertness, suggesting that phase tolerance—ie, the ability to sleep at an abnormal time in the circadian cycle17—decreases with age. However, two field studies involving both eastward and westward travel yielded the opposite results, suggesting that older age may actually protect against jet lag.18–20
Methodologic differences preclude direct comparisons of the studies, as do differences in the age groups studied.
Light exposure can help or hurt, depending on the timing
Our core body temperature dips to its lowest point about 2 to 3 hours before we habitually awake. Exposure to bright light in the hours leading up to this minimum (the inverted triangle in Figure 2) sets our internal clock later (a phase delay)—desirable, say, for someone travelling from New York City to Los Angeles. Conversely, exposure to bright light after this temperature minimum sets the clock earlier.
Inadvertent shifting of circadian phase in the wrong direction (“antidromic re-entrainment”) is common and delays circadian reacclimation and the dissipation of jet lag symptoms.
We discuss ways to reduce antidromic reentrainment in more detail further below.
Other factors
Other factors that contribute to travel fatigue include sleep deprivation (before the flight or en route), acute discomfort as the plane ascends to its cruising altitude,25 and excessive alcohol or caffeine intake during the flight. Although the effects of these factors rapidly diminish once one reaches the travel destination, jet lag will persist until circadian re-entrainment occurs.15
NONDRUG THERAPIES FOR JET LAG SLEEP DISORDER
The goal of treatment is to realign the circadian rhythm in the most rapid and efficient way and to minimize symptoms in the meantime. Frequent shifts to different time zones, often required in business travel, are very difficult to accommodate, and business travelers actually may do better if they remain on their home-based schedule.
One study compared keeping home-based sleep hours as opposed to adopting local sleep hours during a 2-day stay after a 9-hour westward flight.26 Travelers who remained on home-based hours were less sleepy and had lower (ie, better) global jet lag ratings than those who adopted local sleep hours, in part because of better sleep quality and duration. Nevertheless, about one-third of the participants said they preferred to adhere to the local schedule.
Strategic avoidance of, and exposure to, light
If the traveler intends to remain at the destination long enough, he or she can adjust better (and avoid an antidromic process) via strategic avoidance of and exposure to light.24
People travelling east, who want to set their clocks ahead (a phase advance), need to keep to the dark in the 3 hours leading up to the time they reach their minimum core body temperature (depicted as “D” in Figure 3), and then expose themselves to light in the 3 hours immediately after (“L” in Figure 3). Thus, the traveler from Chicago to Paris would do better by avoiding light exposure on arrival, either by remaining in darkness in his or her hotel room, or by wearing dark sunglasses when outdoors. Wearing sunglasses during transit to the hotel would also help avoid light exposure.
When attempting to delay circadian rhythms, the opposite light-dark patterns are sought, as depicted in Figure 4. As flight and layover patterns often do not permit strict adherence to these measures, they represent idealized scenarios.
The first step is to make a grid with a concurrent listing of home and destination times. In the example in Figure 3, the person is traveling seven time zones east. On day 0, a rectangle is drawn around the times representing home-based sleep hours.
Next, we mark the time at which we expect the traveler’s core body temperature to reach its minimum (inverted triangle). If the person habitually sleeps no more than 7 hours per night, then we mark this point as 2 hours before his or her habitual wake-up time; if the person sleeps more than 7 hours, then we place it 3 hours before wake-up time.23,29 This process is repeated at the bottom of the grid to represent the desired sleep schedule at the traveler’s destination. The distance between the home and the destination-based minimum core body temperature symbols represents the required degree of circadian realignment.
If a phase advance is required (eg, if travelling from Chicago to Paris), the core body temperature symbol is drawn on day 1 in the same location as day 0. For each subsequent day, the symbol is moved 1 hour earlier (which is about how fast the internal clock can advance),15,27 until a clock time within 1 hour of the desired destination core body temperature time is reached or satisfactory sleep and daytime functioning are achieved (Figure 3). If a phase delay is required (eg, if travelling from New York City to Los Angeles), the symbol is drawn 2 hours later on day 1 than on day 0 (reflecting the greater ease at which delays are achieved),15,27 with subsequent daily shifts in 2-hour increments, again until a clock time within 1 hour of the desired destination minimum core body temperature time is reached or satisfactory sleep and daytime functioning are achieved.
Requirements for darkness can be met with protective eyewear (ie, dark sunglasses), or by remaining in a dark room. Light requirements can be met with outdoor exposure, with a commercial light box, or with a separate apparatus (eg, goggles, visors) portable enough for travel.
DRUGS TO TREAT JET LAG SLEEP DISORDER
Melatonin appears safe
Most field studies have found that nightly doses of melatonin (2–8 mg) improve the quality of sleep30–32 or alleviate daytime symptoms of jet lag, or both.20,30,31,33–36 Immediate-release preparations appear to be more effective than slow-release ones.31 Although most studies looked exclusively at adaptation to eastward travel,30–32,35,36 one studied westward travel,33 and another assessed melatonin’s effects during both departure and return trips that traversed 11 time zones.34
In studies of preflight dosing, melatonin was scheduled for up to 3 days before departure (and en route in two instances),30,34 at clock hours corresponding to the nocturnal sleep period at the travel destination (consistent times daily), and then for a subsequent 3 to 4 days between a destination time of 22:00 and 00:00 hours (ie, at bedtime).30,31,34–36 Several other studies further simplified this regimen, with participants taking nocturnal melatonin only on arrival at the destination, either for eastward31,32 or for westward travel.33
The study involving solely westward travel (Los Angeles to New Zealand) was the only one of the studies with positive findings that allowed for comparisons between participants who received melatonin before departure (3 days at 5-mg doses, taken between 07:00 and 08:00 Los Angeles time) and continuing for 5 days after arrival at 22:00 to 00:00 New Zealand time, and those who received melatonin beginning only on arrival.33 Significantly better jet lag outcomes were found in the latter group.
An important caveat is that melatonin is sold over the counter as a nutritional supplement and is not regulated by the United States Food and Drug Administration (FDA), so verification of purity of the product is difficult.
A comprehensive review by the National Academy of Sciences stated that, given the available data, short-term use of melatonin in total daily doses of 10 mg or less in healthy adults appears to be safe.37
Benzodiazepine receptor agonists improve sleep, but maybe not sleepiness
The use of standard hypnotics during periods of circadian realignment appears to be commonplace but has not been well studied.20 Trials of the newer benzodiazepine receptor agonists—three studies of zolpidem (Ambien) 10 mg30,38,39 and two of zopiclone 5 to 7.5 mg32,40—found consistently favorable subjective30,38 and objective32,39,40 outcomes in counteracting jet-lag-induced insomnia (for both eastward and westward travel). (Note: Zopiclone is not available in the United States, but its enantiomer eszopiclone [Lunesta] is.) However, the evidence is less clear for daytime symptoms of jet lag, with outcomes reported as favorable,30 equivocal,40 or inaccessible.32,38,39
The discrepancy between studies incorporating systematic daytime assessments may be due to differential medication effects (zolpidem vs zopiclone).
In two studies that compared these standard hypnotics to oral melatonin, one found that zopiclone 5 mg and melatonin 2 mg were equally beneficial with respect to sleep variables (other jet lag symptoms were not assessed).32 In another study, zolpidem 10 mg was superior to melatonin 5 mg for sleep and other jet lag symptoms, and the combination of zolpidem and melatonin was no better than zolpidem alone.30
Importantly, however, adverse effects were more frequent in those taking zolpidem and included nausea, vomiting, and confusion.30 Although these effects were not deemed serious, 14 participants (10%) withdrew from the study.
Stimulants
Caffeine is commonly used to combat the sleepiness of jet lag, but only two controlled field studies have assessed its efficacy.41,42 Both used slow-release preparations at a daily dosage of 300 mg.
In one study, after an eastward flight traversing seven time zones, participants took the pill at 08:00 destination time every day for 5 days.41 Curiously, alertness and other jet lag symptoms were not assessed, but circadian rhythms (determined by levels of cortisol in saliva) were re-entrained at a more rapid rate with caffeine than with placebo, and to a degree comparable with that achieved by exogenous melatonin.
In a follow-up study by the same group, those receiving caffeine were objectively less sleepy (as assessed by multiple sleep latency tests) than those taking melatonin or placebo, but subjective differences between groups were not identified.42 Furthermore, those taking caffeine had significantly more nocturnal sleep complaints, as assessed both objectively and subjectively.
A recent randomized, double-blind, placebo-controlled trial of the stimulant armodafinil (Nuvigil) found less sleepiness on multiple sleep latency testing and a decrease in jet leg symptoms with a dosage of 150 mg than with placebo.43
SHIFT WORK SLEEP DISORDER: DEFINITION, PREDISPOSING FACTORS
Shift work refers to nonstandard work schedules, including on-call duty, rotating shifts, and permanent night work. In the United States, one in five workers works a nonstandard shift.20
While shift work presents obvious difficulties, the diagnosis of shift work sleep disorder is reserved for those who have chronic insomnia or sleepiness at times that are not conducive to the externally demanded sleep-wake schedule, despite having the opportunity for sufficient daytime sleep.1 When defined in such a fashion, this disorder may afflict nearly a third of workers,44 with potential adverse effects on safety, health, and quality of life.
Older age is considered a risk factor for intolerance to shift work.20 In a study of physiologic phase shifts in response to night work, older workers were less able to recover after several night shifts.45 A large survey of police officers working the night shift supported the finding of more sleep disruption and on-duty sleepiness in older people.46
TREATMENT OF SHIFT WORK SLEEP DISORDER
Bright light at work, sunglasses on the way home
Various field studies have described hastening of circadian adaptation (and immediate alerting effects) during night shifts with the use of bright light.20
Boivin and James47 found that workers who received 6 hours of intermittent bright light during their shifts experienced significantly greater phase delays than those who received no such intervention. Those receiving bright light also wore sunglasses during the commute home (to protect from an undesired phase advance), and this has demonstrated favorable effects as an independent intervention.48
Drug treatment of shift work sleep disorder
Melatonin: Mixed results. Two field studies found that taking melatonin (5–6 mg) before the daytime sleep period had a favorable impact on subjective sleep quality.49,50 However, two other studies found no such benefit with doses ranging from 6 to 10 mg.51,52 Differences between these studies—eg, shift schedules, dosages, and the time the melatonin was taken—preclude definitive comparisons.
Effects of melatonin on workplace alertness are indeterminate because of inconsistent measurements of this variable. Importantly, a simulated shift work study found no phase-shifting advantages of melatonin in those who concomitantly used bright light during their work shift with or without morning protective eyewear.48
Hypnotic drugs. In simulation studies and field studies, people taking benzodiazepine receptor agonists have consistently said they sleep better.53–58 A simulation study noted additional benefit in the ability to stay alert during the night shift (assessed by maintenance of wakefulness testing),55 but two other studies saw no changes in manifest sleepiness (assessed with multiple sleep latency tests).53,54 These divergent findings may represent different effects on these two dimensions of sleepiness.
The only field study to assess post-sleep psychomotor performance found no impairments after taking 7.5 mg of zopiclone, a relatively long-acting nonbenzodiazepine hypnotic.57
Stimulants. In the largest trial to date of shift work sleep disorder, modafinil 200 mg (the only drug currently FDA-approved for shift work sleep disorder) had significant benefits compared with placebo with respect to objective measurements of workplace sleepiness, reaction time performance testing, and self-rated improvement of symptoms.59 Perhaps because of the low dose studied, both treated and untreated patients continued to manifest sleepiness within the pathologic range on objective testing.
Although the efficacy of caffeine is well documented as a countermeasure for sleepiness during experimentally induced sleep deprivation,20 very few field trials have specifically addressed impairments associated with shift work sleep disorder. In one study, caffeine at a dose of 4 mg/kg taken 30 minutes before starting a night shift provided objective improvement in both performance and alertness.60
Strategic napping is an additional practical intervention to promote alertness during night shifts, and cumulative data indicate that it provides objective and subjective improvements in alertness and performance.61,62 Earlier timed naps (ie, before or during the early portion of a shift) of short duration (ie, 20 minutes or less) are likely to produce maximal benefit, because they avoid sleep inertia (the grogginess or sleepiness that may follow a long nap), and also because they have no effect on the subsequent daytime sleep bout.61,63
Interventions may also be used in combination. For example, napping in conjunction with caffeine results in a greater degree of increased objective alertness than either intervention alone.60
How about days off?
The recommendations described here presume that shift workers maintain the workday sleep-wake schedule continuously, including when they are not at work. This is likely not a real-world scenario.
Smith et al64 developed a “compromise” phase position, whereby internal rhythms are optimized to facilitate alertness during work and sleepiness during the day, while allowing one to adopt a non-workday sleep schedule that maintains accessibility to family and social activities. In brief, non-workday sleep starts about 5.5 hours earlier than workday sleep; all sleep bouts are followed by brief exposure to bright light (to avoid excessive phase delay); and, as described previously, both workplace bright light and protection from morning light are implemented.
Although further studies are needed to determine whether this regimen is practical in real life, study participants who achieved desired partial phase shifts had performance ratings on a par with baseline levels, and comparable to those in a group that achieved complete re-entrainment.64
Finally, all shift workers need to be encouraged to protect the daytime bedroom environment just as daytime workers protect their nighttime environment. Sleep should be sought in an appropriately darkened and quiet environment, phones and doorbells silenced, and appointments scheduled accordingly.
For people who must travel long distances east or west by air or who must work the night shift, some relief is possible for the grogginess and disorientation that often ensue. The problems arise from the body’s internal clock being out of sync with the sun. Part of the solution involves helping reset the internal clock, or sometimes, preventing it from resetting itself.
This review will focus on jet lag sleep disorder and shift work sleep disorder, with an emphasis on the causes, the clinical assessment, and evidence-based treatment options.
WHEN THE INTERNAL CLOCK IS OUT OF SYNC WITH THE SUN
Circadian rhythm sleep disorders are the result of dyssynchrony between the body’s internal clock and the external 24-hour light-dark cycle. Patients typically present with insomnia or excessive somnolence. These disorders may represent an intrinsic disorder, such as delayed or advanced sleep-phase disorder, or may be the result of transmeridian air travel or working nonstandard shifts.1
The intrinsic human circadian period is typically slightly longer than 24 hours,9 but it is synchronized (“entrained”) to the 24-hour day by various environmental inputs, or zeitgebers (German for “time-givers”), the most important of which is light exposure.10
When the internal clock is out of sync with the sun, the misalignment can result in daytime anergia, alternating complaints of insomnia and hypersomnia, and various other symptoms, including emotional disturbances and gastrointestinal distress. In particular, long-distance air travel or a nocturnal work schedule overwhelms the ability of the intrinsic clock to adjust rapidly enough, and the result is jet lag sleep disorder or shift work sleep disorder.1
TOOLS TO EVALUATE CIRCADIAN RHYTHM DISTURBANCES
A thorough history is the cornerstone of the evaluation for all sleep disorders, and if a circadian rhythm disturbance is suspected, the sleep history is supplemented with specific questions to establish a clear diagnosis.
When assessing for jet lag disorder, ask about:
- The patient’s degree of sleep deprivation before and during travel
- His or her innate circadian preference (ie, whether he or she is a “night owl” or “early bird”)
- Patterns of alcohol and caffeine consumption.
When assessing for shift work disorder, include the above questions and also look for differences in the sleep-wake schedule on working days vs nonworking days, as well as external contributors to poor sleep quality (eg, the degree to which daytime sleep is not “protected”).
The following tools help in acquiring this information.
Sleep diary
In a sleep diary or log, patients record the times that they take naps, maintain consolidated sleep, and subsequently arise. The diary also prompts the patient for information about sleep latency, wakefulness after sleep onset, time in bed, medication and caffeine intake, and the restorative quality of sleep.
While the sleep diary by itself may provide insight into counteractive sleep-related behaviors and misperceptions the patient may have, compliance is often limited. Therefore, the sleep diary is best used in conjunction with actigraphy.
Actigraphy
An actigraph is a wristwatch-size motion detector, typically worn continuously for 7 days or longer. The data it gathers and stores serve as a surrogate measure of various sleep-wake variables.11
Either a sleep diary or actigraphy is required to demonstrate the stability of sleep patterns and circadian preference, but the actigraph typically generates more reliable data.11,12 It is also valuable in assessing the response to treatment of circadian rhythm sleep disorders.13
Are you an early bird or a night owl?
The Morningness-Eveningness questionnaire contains 19 items. Night owls tend to score lower on it than early birds do.14 This information may help some people avoid situations in which they may not do well, such as an early bird going on a permanent night-shift schedule.
Other assessment tools
Polysomnography is used primarily to rule out sleep-disordered breathing; it is not indicated for routine evaluation of circadian rhythm sleep disorders.
The minimum core body temperature and the peak melatonin secretion follow a 24-hour cycle. Although these measures are often used in research, they are not routinely used in clinical practice. (The minimum core body temperature is discussed further below.)
JET LAG SLEEP DISORDER
Jet lag results from air travel across multiple time zones, with a resultant discordance between the internal circadian clock and the destination’s light-dark cycle. Most sufferers report sleeping poorly at night and feeling groggy during the day, and some also experience general malaise and gastrointestinal distress.1
The severity depends on a number of variables.
Going west is easier than going east
Westward travel is normally less taxing than eastward travel, as it requires setting one’s internal clock later rather than earlier. Presumably, because the circadian period tends to exceed 24 hours, we can move our internal clock later by about 2 hours per day, but we can move it earlier by only 1 to 1.5 hours.15,16
The more time zones crossed, the longer it takes the circadian pacemaker to re-entrain and the longer-lasting and more severe are the symptoms of jet lag. Travel across one or two time zones is only transiently troublesome.
Does age affect jet lag?
Whether age affects the severity of jet lag is not yet known.
In a study of simulated jet lag (requiring a 6-hour advance), middle-aged people (ages 37 to 52) experienced a greater degree of fragmented sleep on polysomnography than younger ones (ages 18 to 25). The older group also had greater impairment in daytime alertness, suggesting that phase tolerance—ie, the ability to sleep at an abnormal time in the circadian cycle17—decreases with age. However, two field studies involving both eastward and westward travel yielded the opposite results, suggesting that older age may actually protect against jet lag.18–20
Methodologic differences preclude direct comparisons of the studies, as do differences in the age groups studied.
Light exposure can help or hurt, depending on the timing
Our core body temperature dips to its lowest point about 2 to 3 hours before we habitually awake. Exposure to bright light in the hours leading up to this minimum (the inverted triangle in Figure 2) sets our internal clock later (a phase delay)—desirable, say, for someone travelling from New York City to Los Angeles. Conversely, exposure to bright light after this temperature minimum sets the clock earlier.
Inadvertent shifting of circadian phase in the wrong direction (“antidromic re-entrainment”) is common and delays circadian reacclimation and the dissipation of jet lag symptoms.
We discuss ways to reduce antidromic reentrainment in more detail further below.
Other factors
Other factors that contribute to travel fatigue include sleep deprivation (before the flight or en route), acute discomfort as the plane ascends to its cruising altitude,25 and excessive alcohol or caffeine intake during the flight. Although the effects of these factors rapidly diminish once one reaches the travel destination, jet lag will persist until circadian re-entrainment occurs.15
NONDRUG THERAPIES FOR JET LAG SLEEP DISORDER
The goal of treatment is to realign the circadian rhythm in the most rapid and efficient way and to minimize symptoms in the meantime. Frequent shifts to different time zones, often required in business travel, are very difficult to accommodate, and business travelers actually may do better if they remain on their home-based schedule.
One study compared keeping home-based sleep hours as opposed to adopting local sleep hours during a 2-day stay after a 9-hour westward flight.26 Travelers who remained on home-based hours were less sleepy and had lower (ie, better) global jet lag ratings than those who adopted local sleep hours, in part because of better sleep quality and duration. Nevertheless, about one-third of the participants said they preferred to adhere to the local schedule.
Strategic avoidance of, and exposure to, light
If the traveler intends to remain at the destination long enough, he or she can adjust better (and avoid an antidromic process) via strategic avoidance of and exposure to light.24
People travelling east, who want to set their clocks ahead (a phase advance), need to keep to the dark in the 3 hours leading up to the time they reach their minimum core body temperature (depicted as “D” in Figure 3), and then expose themselves to light in the 3 hours immediately after (“L” in Figure 3). Thus, the traveler from Chicago to Paris would do better by avoiding light exposure on arrival, either by remaining in darkness in his or her hotel room, or by wearing dark sunglasses when outdoors. Wearing sunglasses during transit to the hotel would also help avoid light exposure.
When attempting to delay circadian rhythms, the opposite light-dark patterns are sought, as depicted in Figure 4. As flight and layover patterns often do not permit strict adherence to these measures, they represent idealized scenarios.
The first step is to make a grid with a concurrent listing of home and destination times. In the example in Figure 3, the person is traveling seven time zones east. On day 0, a rectangle is drawn around the times representing home-based sleep hours.
Next, we mark the time at which we expect the traveler’s core body temperature to reach its minimum (inverted triangle). If the person habitually sleeps no more than 7 hours per night, then we mark this point as 2 hours before his or her habitual wake-up time; if the person sleeps more than 7 hours, then we place it 3 hours before wake-up time.23,29 This process is repeated at the bottom of the grid to represent the desired sleep schedule at the traveler’s destination. The distance between the home and the destination-based minimum core body temperature symbols represents the required degree of circadian realignment.
If a phase advance is required (eg, if travelling from Chicago to Paris), the core body temperature symbol is drawn on day 1 in the same location as day 0. For each subsequent day, the symbol is moved 1 hour earlier (which is about how fast the internal clock can advance),15,27 until a clock time within 1 hour of the desired destination core body temperature time is reached or satisfactory sleep and daytime functioning are achieved (Figure 3). If a phase delay is required (eg, if travelling from New York City to Los Angeles), the symbol is drawn 2 hours later on day 1 than on day 0 (reflecting the greater ease at which delays are achieved),15,27 with subsequent daily shifts in 2-hour increments, again until a clock time within 1 hour of the desired destination minimum core body temperature time is reached or satisfactory sleep and daytime functioning are achieved.
Requirements for darkness can be met with protective eyewear (ie, dark sunglasses), or by remaining in a dark room. Light requirements can be met with outdoor exposure, with a commercial light box, or with a separate apparatus (eg, goggles, visors) portable enough for travel.
DRUGS TO TREAT JET LAG SLEEP DISORDER
Melatonin appears safe
Most field studies have found that nightly doses of melatonin (2–8 mg) improve the quality of sleep30–32 or alleviate daytime symptoms of jet lag, or both.20,30,31,33–36 Immediate-release preparations appear to be more effective than slow-release ones.31 Although most studies looked exclusively at adaptation to eastward travel,30–32,35,36 one studied westward travel,33 and another assessed melatonin’s effects during both departure and return trips that traversed 11 time zones.34
In studies of preflight dosing, melatonin was scheduled for up to 3 days before departure (and en route in two instances),30,34 at clock hours corresponding to the nocturnal sleep period at the travel destination (consistent times daily), and then for a subsequent 3 to 4 days between a destination time of 22:00 and 00:00 hours (ie, at bedtime).30,31,34–36 Several other studies further simplified this regimen, with participants taking nocturnal melatonin only on arrival at the destination, either for eastward31,32 or for westward travel.33
The study involving solely westward travel (Los Angeles to New Zealand) was the only one of the studies with positive findings that allowed for comparisons between participants who received melatonin before departure (3 days at 5-mg doses, taken between 07:00 and 08:00 Los Angeles time) and continuing for 5 days after arrival at 22:00 to 00:00 New Zealand time, and those who received melatonin beginning only on arrival.33 Significantly better jet lag outcomes were found in the latter group.
An important caveat is that melatonin is sold over the counter as a nutritional supplement and is not regulated by the United States Food and Drug Administration (FDA), so verification of purity of the product is difficult.
A comprehensive review by the National Academy of Sciences stated that, given the available data, short-term use of melatonin in total daily doses of 10 mg or less in healthy adults appears to be safe.37
Benzodiazepine receptor agonists improve sleep, but maybe not sleepiness
The use of standard hypnotics during periods of circadian realignment appears to be commonplace but has not been well studied.20 Trials of the newer benzodiazepine receptor agonists—three studies of zolpidem (Ambien) 10 mg30,38,39 and two of zopiclone 5 to 7.5 mg32,40—found consistently favorable subjective30,38 and objective32,39,40 outcomes in counteracting jet-lag-induced insomnia (for both eastward and westward travel). (Note: Zopiclone is not available in the United States, but its enantiomer eszopiclone [Lunesta] is.) However, the evidence is less clear for daytime symptoms of jet lag, with outcomes reported as favorable,30 equivocal,40 or inaccessible.32,38,39
The discrepancy between studies incorporating systematic daytime assessments may be due to differential medication effects (zolpidem vs zopiclone).
In two studies that compared these standard hypnotics to oral melatonin, one found that zopiclone 5 mg and melatonin 2 mg were equally beneficial with respect to sleep variables (other jet lag symptoms were not assessed).32 In another study, zolpidem 10 mg was superior to melatonin 5 mg for sleep and other jet lag symptoms, and the combination of zolpidem and melatonin was no better than zolpidem alone.30
Importantly, however, adverse effects were more frequent in those taking zolpidem and included nausea, vomiting, and confusion.30 Although these effects were not deemed serious, 14 participants (10%) withdrew from the study.
Stimulants
Caffeine is commonly used to combat the sleepiness of jet lag, but only two controlled field studies have assessed its efficacy.41,42 Both used slow-release preparations at a daily dosage of 300 mg.
In one study, after an eastward flight traversing seven time zones, participants took the pill at 08:00 destination time every day for 5 days.41 Curiously, alertness and other jet lag symptoms were not assessed, but circadian rhythms (determined by levels of cortisol in saliva) were re-entrained at a more rapid rate with caffeine than with placebo, and to a degree comparable with that achieved by exogenous melatonin.
In a follow-up study by the same group, those receiving caffeine were objectively less sleepy (as assessed by multiple sleep latency tests) than those taking melatonin or placebo, but subjective differences between groups were not identified.42 Furthermore, those taking caffeine had significantly more nocturnal sleep complaints, as assessed both objectively and subjectively.
A recent randomized, double-blind, placebo-controlled trial of the stimulant armodafinil (Nuvigil) found less sleepiness on multiple sleep latency testing and a decrease in jet leg symptoms with a dosage of 150 mg than with placebo.43
SHIFT WORK SLEEP DISORDER: DEFINITION, PREDISPOSING FACTORS
Shift work refers to nonstandard work schedules, including on-call duty, rotating shifts, and permanent night work. In the United States, one in five workers works a nonstandard shift.20
While shift work presents obvious difficulties, the diagnosis of shift work sleep disorder is reserved for those who have chronic insomnia or sleepiness at times that are not conducive to the externally demanded sleep-wake schedule, despite having the opportunity for sufficient daytime sleep.1 When defined in such a fashion, this disorder may afflict nearly a third of workers,44 with potential adverse effects on safety, health, and quality of life.
Older age is considered a risk factor for intolerance to shift work.20 In a study of physiologic phase shifts in response to night work, older workers were less able to recover after several night shifts.45 A large survey of police officers working the night shift supported the finding of more sleep disruption and on-duty sleepiness in older people.46
TREATMENT OF SHIFT WORK SLEEP DISORDER
Bright light at work, sunglasses on the way home
Various field studies have described hastening of circadian adaptation (and immediate alerting effects) during night shifts with the use of bright light.20
Boivin and James47 found that workers who received 6 hours of intermittent bright light during their shifts experienced significantly greater phase delays than those who received no such intervention. Those receiving bright light also wore sunglasses during the commute home (to protect from an undesired phase advance), and this has demonstrated favorable effects as an independent intervention.48
Drug treatment of shift work sleep disorder
Melatonin: Mixed results. Two field studies found that taking melatonin (5–6 mg) before the daytime sleep period had a favorable impact on subjective sleep quality.49,50 However, two other studies found no such benefit with doses ranging from 6 to 10 mg.51,52 Differences between these studies—eg, shift schedules, dosages, and the time the melatonin was taken—preclude definitive comparisons.
Effects of melatonin on workplace alertness are indeterminate because of inconsistent measurements of this variable. Importantly, a simulated shift work study found no phase-shifting advantages of melatonin in those who concomitantly used bright light during their work shift with or without morning protective eyewear.48
Hypnotic drugs. In simulation studies and field studies, people taking benzodiazepine receptor agonists have consistently said they sleep better.53–58 A simulation study noted additional benefit in the ability to stay alert during the night shift (assessed by maintenance of wakefulness testing),55 but two other studies saw no changes in manifest sleepiness (assessed with multiple sleep latency tests).53,54 These divergent findings may represent different effects on these two dimensions of sleepiness.
The only field study to assess post-sleep psychomotor performance found no impairments after taking 7.5 mg of zopiclone, a relatively long-acting nonbenzodiazepine hypnotic.57
Stimulants. In the largest trial to date of shift work sleep disorder, modafinil 200 mg (the only drug currently FDA-approved for shift work sleep disorder) had significant benefits compared with placebo with respect to objective measurements of workplace sleepiness, reaction time performance testing, and self-rated improvement of symptoms.59 Perhaps because of the low dose studied, both treated and untreated patients continued to manifest sleepiness within the pathologic range on objective testing.
Although the efficacy of caffeine is well documented as a countermeasure for sleepiness during experimentally induced sleep deprivation,20 very few field trials have specifically addressed impairments associated with shift work sleep disorder. In one study, caffeine at a dose of 4 mg/kg taken 30 minutes before starting a night shift provided objective improvement in both performance and alertness.60
Strategic napping is an additional practical intervention to promote alertness during night shifts, and cumulative data indicate that it provides objective and subjective improvements in alertness and performance.61,62 Earlier timed naps (ie, before or during the early portion of a shift) of short duration (ie, 20 minutes or less) are likely to produce maximal benefit, because they avoid sleep inertia (the grogginess or sleepiness that may follow a long nap), and also because they have no effect on the subsequent daytime sleep bout.61,63
Interventions may also be used in combination. For example, napping in conjunction with caffeine results in a greater degree of increased objective alertness than either intervention alone.60
How about days off?
The recommendations described here presume that shift workers maintain the workday sleep-wake schedule continuously, including when they are not at work. This is likely not a real-world scenario.
Smith et al64 developed a “compromise” phase position, whereby internal rhythms are optimized to facilitate alertness during work and sleepiness during the day, while allowing one to adopt a non-workday sleep schedule that maintains accessibility to family and social activities. In brief, non-workday sleep starts about 5.5 hours earlier than workday sleep; all sleep bouts are followed by brief exposure to bright light (to avoid excessive phase delay); and, as described previously, both workplace bright light and protection from morning light are implemented.
Although further studies are needed to determine whether this regimen is practical in real life, study participants who achieved desired partial phase shifts had performance ratings on a par with baseline levels, and comparable to those in a group that achieved complete re-entrainment.64
Finally, all shift workers need to be encouraged to protect the daytime bedroom environment just as daytime workers protect their nighttime environment. Sleep should be sought in an appropriately darkened and quiet environment, phones and doorbells silenced, and appointments scheduled accordingly.
- International Classification of Sleep Disorders: Diagnostic and Coding Manual/American Academy of Sleep Medicine. 2nd ed. Westchester, IL: American Academy of Sleep Medicine; 2005.
- Borbély AA, Achermann P. Concepts and models of sleep regulation: an overview. J Sleep Res 1992; 1:63–79.
- Carskadon MA, Dement WC. Effects of total sleep loss on sleep tendency. Percept Mot Skills 1979; 48:495–506.
- Beersma DG, Gordijn MC. Circadian control of the sleep-wake cycle. Physiol Behav 2007; 90:190–195.
- Moore RY, Eichler VB. Loss of a circadian adrenal corticosterone rhythm following suprachiasmatic lesions in the rat. Brain Res 1972; 42:201–206.
- Stephan FK, Zucker I. Circadian rhythms in drinking behavior and locomotor activity of rats are eliminated by hypothalamic lesions. Proc Natl Acad Sci U S A 1972; 69:1583–1586.
- Welsh DK, Logothetis DE, Meister M, Reppert SM. Individual neurons dissociated from rat suprachiasmatic nucleus express independently phased circadian firing rhythms. Neuron 1995; 14:697–706.
- Ralph MR, Foster RG, Davis FC, Menaker M. Transplanted suprachiasmatic nucleus determines circadian period. Science 1990; 247:975–978.
- Czeisler CA, Duffy JF, Shanahan TL, et al. Stability, precision, and near-24-hour period of the human circadian pacemaker. Science 1999; 284:2177–2181.
- Waterhouse JM, DeCoursey PJ. Human circadian organization. In:Dunlap JC, Loros JJ, DeCoursey PJ, editors. Chronobiology: Biological Timekeeping. Sunderland, MA: Sinauer Associates; 2004:291–324.
- Morgenthaler T, Alessi C, Friedman L, et al; Standards of Practice Committee; American Academy of Sleep Medicine. Practice parameters for the use of actigraphy in the assessment of sleep and sleep disorders: an update for 2007. Sleep 2007; 30:519–529.
- Bradshaw DA, Yanagi MA, Pak ES, Peery TS, Ruff GA. Nightly sleep duration in the 2-week period preceding multiple sleep latency testing. J Clin Sleep Med 2007; 3:613–619.
- Morgenthaler TI, Lee-Chiong T, Alessi C, et al; Standards of Practice Committee of the American Academy of Sleep Medicine. Practice parameters for the clinical evaluation and treatment of circadian rhythm sleep disorders. An American Academy of Sleep Medicine report. Sleep 2007; 30:1445–1459.
- Horne JA, Ostberg O. A self-assessment questionnaire to determine morningness-eveningness in human circadian rhythms. Int J Chronobiol 1976; 4:97–110.
- Waterhouse J, Reilly T, Atkinson G, Edwards B. Jet lag: trends and coping strategies. Lancet 2007; 369:1117–1129.
- Eastman CI, Gazda CJ, Burgess HJ, Crowley SJ, Fogg LF. Advancing circadian rhythms before eastward flight: a strategy to prevent or reduce jet lag. Sleep 2005; 28:33–44.
- Moline ML, Pollak CP, Monk TH, et al. Age-related differences in recovery from simulated jet lag. Sleep 1992; 15:28–40.
- Waterhouse J, Edwards B, Nevill A, et al. Identifying some determinants of “jet lag” and its symptoms: a study of athletes and other travellers. Br J Sports Med 2002; 36:54–60.
- Tresguerres JA, Ariznavarreta C, Granados B, et al. Circadian urinary 6-sulphatoxymelatonin, cortisol excretion and locomotor activity in airline pilots during transmeridian flights. J Pineal Res 2001; 31:16–22.
- Sack RL, Auckley D, Auger RR, et al; American Academy of Sleep Medicine. Circadian rhythm sleep disorders: part I, basic principles, shift work and jet lag disorders. An American Academy of Sleep Medicine review. Sleep 2007; 30:1460–1483.
- Burgess HJ, Sharkey KM, Eastman CI. Bright light, dark and melatonin can promote circadian adaptation in night shift workers. Sleep Med Rev 2002; 6:407–420.
- Lewy AJ, Bauer VK, Saeeduddin A, et al. The human phase response curve (PRC) to melatonin is about 12 hours out of phase with the PRC to light. Chronobiol Int 1998; 15:71–83.
- Burgess HJ, Eastman CT. Prevention of Jet Lag. 2010. http://pier.acponline.org/physicians/screening/prev1015/prev1015.html. Accessed June 25, 2010.
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- Muhm JM, Rock PB, McMullin DL, et al. Effect of aircraft-cabin altitude on passenger discomfort. N Engl J Med 2007; 357:18–27.
- Lowden A, Akerstedt T. Retaining home-base sleep hours to prevent jet lag in connection with a westward flight across nine time zones. Chronobiol Int 1998; 15:365–376.
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- Sallinen M, Härmä M, Akerstedt T, Rosa R, Lillqvist O. Promoting alertness with a short nap during a night shift. J Sleep Res 1998; 7:240–247.
- Garbarino S, Mascialino B, Penco MA, et al. Professional shift-work drivers who adopt prophylactic naps can reduce the risk of car accidents during night work. Sleep 2004; 27:1295–1302.
- Purnell MT, Feyer AM, Herbison GP. The impact of a nap opportunity during the night shift on the performance and alertness of 12-h shift workers. J Sleep Res 2002; 11:219–227.
- Smith MR, Fogg LF, Eastman CI. A compromise circadian phase position for permanent night work improves mood, fatigue, and performance. Sleep 2009; 32:1481–1489.
- International Classification of Sleep Disorders: Diagnostic and Coding Manual/American Academy of Sleep Medicine. 2nd ed. Westchester, IL: American Academy of Sleep Medicine; 2005.
- Borbély AA, Achermann P. Concepts and models of sleep regulation: an overview. J Sleep Res 1992; 1:63–79.
- Carskadon MA, Dement WC. Effects of total sleep loss on sleep tendency. Percept Mot Skills 1979; 48:495–506.
- Beersma DG, Gordijn MC. Circadian control of the sleep-wake cycle. Physiol Behav 2007; 90:190–195.
- Moore RY, Eichler VB. Loss of a circadian adrenal corticosterone rhythm following suprachiasmatic lesions in the rat. Brain Res 1972; 42:201–206.
- Stephan FK, Zucker I. Circadian rhythms in drinking behavior and locomotor activity of rats are eliminated by hypothalamic lesions. Proc Natl Acad Sci U S A 1972; 69:1583–1586.
- Welsh DK, Logothetis DE, Meister M, Reppert SM. Individual neurons dissociated from rat suprachiasmatic nucleus express independently phased circadian firing rhythms. Neuron 1995; 14:697–706.
- Ralph MR, Foster RG, Davis FC, Menaker M. Transplanted suprachiasmatic nucleus determines circadian period. Science 1990; 247:975–978.
- Czeisler CA, Duffy JF, Shanahan TL, et al. Stability, precision, and near-24-hour period of the human circadian pacemaker. Science 1999; 284:2177–2181.
- Waterhouse JM, DeCoursey PJ. Human circadian organization. In:Dunlap JC, Loros JJ, DeCoursey PJ, editors. Chronobiology: Biological Timekeeping. Sunderland, MA: Sinauer Associates; 2004:291–324.
- Morgenthaler T, Alessi C, Friedman L, et al; Standards of Practice Committee; American Academy of Sleep Medicine. Practice parameters for the use of actigraphy in the assessment of sleep and sleep disorders: an update for 2007. Sleep 2007; 30:519–529.
- Bradshaw DA, Yanagi MA, Pak ES, Peery TS, Ruff GA. Nightly sleep duration in the 2-week period preceding multiple sleep latency testing. J Clin Sleep Med 2007; 3:613–619.
- Morgenthaler TI, Lee-Chiong T, Alessi C, et al; Standards of Practice Committee of the American Academy of Sleep Medicine. Practice parameters for the clinical evaluation and treatment of circadian rhythm sleep disorders. An American Academy of Sleep Medicine report. Sleep 2007; 30:1445–1459.
- Horne JA, Ostberg O. A self-assessment questionnaire to determine morningness-eveningness in human circadian rhythms. Int J Chronobiol 1976; 4:97–110.
- Waterhouse J, Reilly T, Atkinson G, Edwards B. Jet lag: trends and coping strategies. Lancet 2007; 369:1117–1129.
- Eastman CI, Gazda CJ, Burgess HJ, Crowley SJ, Fogg LF. Advancing circadian rhythms before eastward flight: a strategy to prevent or reduce jet lag. Sleep 2005; 28:33–44.
- Moline ML, Pollak CP, Monk TH, et al. Age-related differences in recovery from simulated jet lag. Sleep 1992; 15:28–40.
- Waterhouse J, Edwards B, Nevill A, et al. Identifying some determinants of “jet lag” and its symptoms: a study of athletes and other travellers. Br J Sports Med 2002; 36:54–60.
- Tresguerres JA, Ariznavarreta C, Granados B, et al. Circadian urinary 6-sulphatoxymelatonin, cortisol excretion and locomotor activity in airline pilots during transmeridian flights. J Pineal Res 2001; 31:16–22.
- Sack RL, Auckley D, Auger RR, et al; American Academy of Sleep Medicine. Circadian rhythm sleep disorders: part I, basic principles, shift work and jet lag disorders. An American Academy of Sleep Medicine review. Sleep 2007; 30:1460–1483.
- Burgess HJ, Sharkey KM, Eastman CI. Bright light, dark and melatonin can promote circadian adaptation in night shift workers. Sleep Med Rev 2002; 6:407–420.
- Lewy AJ, Bauer VK, Saeeduddin A, et al. The human phase response curve (PRC) to melatonin is about 12 hours out of phase with the PRC to light. Chronobiol Int 1998; 15:71–83.
- Burgess HJ, Eastman CT. Prevention of Jet Lag. 2010. http://pier.acponline.org/physicians/screening/prev1015/prev1015.html. Accessed June 25, 2010.
- Daan S, Lewy AJ. Scheduled exposure to daylight: a potential strategy to reduce “jet lag” following transmeridian flight. Psychopharmacol Bull 1984; 20:566–568.
- Muhm JM, Rock PB, McMullin DL, et al. Effect of aircraft-cabin altitude on passenger discomfort. N Engl J Med 2007; 357:18–27.
- Lowden A, Akerstedt T. Retaining home-base sleep hours to prevent jet lag in connection with a westward flight across nine time zones. Chronobiol Int 1998; 15:365–376.
- Eastman CI, Burgess HJ. How to travel the world without jet lag. Sleep Med Clin 2009; 4:241–255.
- Revell VL, Eastman CI. How to trick mother nature into letting you fly around or stay up all night. J Biol Rhythms 2005; 20:353–365.
- Cagnacci A, Elliott JA, Yen SS. Melatonin: a major regulator of the circadian rhythm of core temperature in humans. J Clin Endocrinol Metab 1992; 75:447–452.
- Suhner A, Schlagenhauf P, Höfer I, Johnson R, Tschopp A, Steffen R. Effectiveness and tolerability of melatonin and zolpidem for the alleviation of jet lag. Aviat Space Environ Med 2001; 72:638–646.
- Suhner A, Schlagenhauf P, Johnson R, Tschopp A, Steffen R. Comparative study to determine the optimal melatonin dosage form for the alleviation of jet lag. Chronobiol Int 1998; 15:655–666.
- Paul MA, Gray G, Sardana TM, Pigeau RA. Melatonin and zopiclone as facilitators of early circadian sleep in operational air transport crews. Aviat Space Environ Med 2004; 75:439–443.
- Petrie K, Dawson AG, Thompson L, Brook R. A double-blind trial of melatonin as a treatment for jet lag in international cabin crew. Biol Psychiatry 1993; 33:526–530.
- Petrie K, Conaglen JV, Thompson L, Chamberlain K. Effect of melatonin on jet lag after long haul flights. BMJ 1989; 298:705–707.
- Arendt J, Aldhous M, Marks V. Alleviation of jet lag by melatonin: preliminary results of controlled double blind trial. Br Med J (Clin Res Ed) 1986; 292:1170.
- Claustrat B, Brun J, David M, Sassolas G, Chazot G. Melatonin and jet lag: confirmatory result using a simplified protocol. Biol Psychiatry 1992; 32:705–711.
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- Jamieson AO, Zammit GK, Rosenberg RS, Davis JR, Walsh JK. Zolpidem reduces the sleep disturbance of jet lag. Sleep Med 2001; 2:423–430.
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- Daurat A, Benoit O, Buguet A. Effects of zopiclone on the rest/activity rhythm after a westward flight across five time zones. Psychopharmacology (Berl) 2000; 149:241–245.
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- Beaumont M, Batéjat D, Piérard C, et al. Caffeine or melatonin effects on sleep and sleepiness after rapid eastward transmeridian travel. J Appl Physiol 2004; 96:50–58.
- Rosenberg RP, Bogan RK, Tiller JM, et al. A phase 3, double-blind, randomized, placebo-controlled study of armodafinil for excessive sleepiness associated with jet lag disorder. Mayo Clin Proc 2010; 85:630–638.
- Drake CL, Roehrs T, Richardson G, Walsh JK, Roth T. Shift work sleep disorder: prevalence and consequences beyond that of symptomatic day workers. Sleep 2004; 27:1453–1462.
- Härmä MI, Hakola T, Akerstedt T, Laitinen JT. Age and adjustment to night work. Occup Environ Med 1994; 51:568–573.
- Smith L, Mason C. Reducing night shift exposure: a pilot study of rota, night shift and age effects on sleepiness and fatigue. J Hum Ergol (Tokyo) 2001; 30:83–87.
- Boivin DB, James FO. Circadian adaptation to night-shift work by judicious light and darkness exposure. J Biol Rhythms 2002; 17:556–567.
- Crowley SJ, Lee C, Tseng CY, Fogg LF, Eastman CI. Combinations of bright light, scheduled dark, sunglasses, and melatonin to facilitate circadian entrainment to night shift work. J Biol Rhythms 2003; 18:513–523.
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- Porcù S, Bellatreccia A, Ferrara M, Casagrande M. Performance, ability to stay awake, and tendency to fall asleep during the night after a diurnal sleep with temazepam or placebo. Sleep 1997; 20:535–541.
- Monchesky TC, Billings BJ, Phillips R, Bourgouin J. Zopiclone in insomniac shiftworkers. Evaluation of its hypnotic properties and its effects on mood and work performance. Int Arch Occup Environ Health 1989; 61:255–259.
- Moon CA, Hindmarch I, Holland RL. The effect of zopiclone 7.5 mg on the sleep, mood and performance of shift workers. Int Clin Psychopharmacol 1990; 5(suppl 2):79–83.
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KEY POINTS
- Symptoms include daytime anergia, alternating complaints of insomnia and hypersomnia, emotional disturbances, and gastrointestinal distress. The severity depends on the degree and the duration of dyssynchrony, as well as on innate factors such as age and whether the patient is an “early bird” or a “night owl.”
- Drug treatment addresses sleep-related symptoms (eg, somnolence, insomnia) and attempts to hasten circadian reacclimation.
- Exposure to bright light in the hours leading up to the patient’s minimum core body temperature tends to push the internal clock later in time, whereas bright light in the hours immediately afterward pushes the clock earlier in time.
Update in intensive care medicine: Studies that challenged our practice in the last 5 years
We have seen significant growth in clinical research in critical care medicine in the last decade. Advances have been made in many important areas in this field; of these, advances in treating septic shock and acute respiratory distress syndrome (ARDS), and also in supportive therapies for critically ill patients (eg, sedatives, insulin), have perhaps received the most attention.
Of note, several once-established therapies in these areas have failed the test of time, as the result of evidence from more-recent clinical trials. For example, recent studies have shown that a pulmonary arterial catheter does not improve outcomes in patients with ARDS. Similarly, what used to be “optimal” fluid management in patients with ARDS is no longer considered appropriate.
In this review, we summarize eight major studies in critical care medicine published in the last 5 years, studies that have contributed to changes in our practice in the intensive care unit (ICU).
FLUID MANAGEMENT IN ARDS
Key points
- In patients with acute lung injury (ALI) and ARDS, fluid restriction is associated with better outcomes than a liberal fluid policy.
- A pulmonary arterial catheter is not necessary and, compared with a central venous catheter, may result in more complications in patients with ALI and ARDS.
Background
Fluid management practices in patients with ARDS have been extremely variable. Two different approaches are commonly used: the liberal or “wet” approach to optimize tissue perfusion and the “dry” approach, which focuses on reducing lung edema. Given that most deaths attributed to ARDS result from extrapulmonary organ failure, aggressive fluid restriction has been the less popular approach.
Additionally, although earlier studies and meta-analyses suggested that the use of a pulmonary arterial catheter was not associated with better outcomes in critically ill patients,1 controversy remained regarding the value of a pulmonary arterial catheter compared with a central venous catheter in guiding fluid management in patients with ARDS, and data were insufficient to prove one strategy better than the other.
The Fluids and Catheter Treatment Trial (FACTT)
NATIONAL HEART, LUNG, AND BLOOD INSTITUTE ACUTE RESPIRATORY DISTRESS SYNDROME (ARDS) CLINICAL TRIALS NETWORK; WIEDEMANN HP, WHEELER AP, BERNARD GR, ET AL. COMPARISON OF TWO FLUID-MANAGEMENT STRATEGIES IN ACUTE LUNG INJURY. N ENGL J MED 2006; 354:2564–2575.
NATIONAL HEART, LUNG, AND BLOOD INSTITUTE ACUTE RESPIRATORY DISTRESS SYNDROME (ARDS) CLINICAL TRIALS NETWORK; WHEELER AP, BERNARD GR, THOMPSON BT, ET AL. PULMONARY-ARTERY VERSUS CENTRAL VENOUS CATHETER TO GUIDE TREATMENT OF ACUTE LUNG INJURY. N ENGL J MED 2006; 354:2213–2224.
The Fluids and Catheter Treatment Trial (FACTT) compared two fluid strategies2 and also the utility of a pulmonary arterial catheter vs a central venous catheter3 in patients with ALI or ARDS.
This two-by-two factorial trial randomized 1,000 patients to be treated according to either a conservative (fluid-restrictive or “dry”) or a liberal (“wet”) fluid management strategy for 7 days. Additionally, they were randomly assigned to receive either a central venous catheter or a pulmonary arterial catheter. The trial thus had four treatment groups:
- Fluid-restricted and a central venous catheter, with a goal of keeping the central venous pressure below 4 mm Hg
- Fluid-restricted and a pulmonary arterial catheter: fluids were restricted and diuretics were given to keep the pulmonary artery occlusion pressure below 8 mm Hg
- Fluid-liberal and a central venous catheter: fluids were given to keep the central venous pressure between 10 and 14 mm Hg
- Fluid-liberal and a pulmonary arterial catheter: fluids were given to keep the pulmonary artery occlusion pressure between 14 and 18 mm Hg.
The primary end point was the mortality rate at 60 days. Secondary end points included the number of ventilator-free days and organ-failure-free days and parameters of lung physiology. All patients were managed with a low-tidal-volume strategy.
The ‘dry’ strategy was better
The cumulative fluid balance was −136 mL ± 491 mL in the “dry” group and 6,992 mL ± 502 mL in the “wet” group, a difference of more than 7 L (P < .0001). Of note, before randomization, the patients were already fluid-positive, with a mean total fluid balance of +2,700 mL).2
At 60 days, no statistically significant difference in mortality rate was seen between the fluid-management groups (25.5% in the dry group vs 28.4% in the wet group (P = .30). Nevertheless, patients in the dry group had better oxygenation indices and lung injury scores (including lower plateau airway pressure), resulting in more ventilator-free days (14.6 ± 0.5 vs 12.1 ± 0.5; P = .0002) and ICU-free days (13.4 ± 0.4 vs 11.2 ± 0.4; P = .0003).2
Although those in the dry-strategy group had a slightly lower cardiac index and mean arterial pressure, they did not have a higher incidence of shock.
More importantly, the dry group did not have a higher rate of nonpulmonary organ failure. Serum creatinine and blood urea nitrogen concentrations were slightly higher in this group, but this was not associated with a higher incidence of renal failure or the use of dialysis: 10% in the dry-strategy group vs 14% in the wet-strategy group; P = .0642).2
No advantage with a pulmonary arterial catheter
The mortality rate did not differ between the catheter groups. However, the patients who received a pulmonary arterial catheter stayed in the ICU 0.2 days longer and had twice as many nonfatal cardiac arrhythmias as those who received a central venous catheter.3
Comments
The liberal fluid-strategy group had fluid balances similar to those seen in previous National Institutes of Health ARDS Network trials in which fluid management was not controlled. This suggests that the liberal fluid strategy reflects usual clinical practice.
Although the goals used in this study (central venous pressure < 4 mm Hg or pulmonary artery occlusion pressure < 8 mm Hg) could be difficult to achieve in clinical practice, a conservative strategy of fluid management is preferred in patients with ALI or ARDS, given the benefits observed in this trial.
A pulmonary arterial catheter is not indicated to guide hemodynamic management of patients with ARDS.
CORTICOSTEROID USE IN ARDS
Key points
- In selected patients with ARDS, the prolonged use of corticosteroids may result in better oxygenation and a shorter duration of mechanical ventilation.
- Late use of corticosteroids in patients with ARDS (> 14 days after diagnosis) is not indicated and may increase the risk of death.
- The role of corticosteroids in early ARDS (< 7 days after diagnosis) remains controversial.
Background
Systemic corticosteroid therapy was commonly used in ARDS patients in the 1970s and 1980s. However, a single-center study published in the late 1980s showed that a corticosteroid in high doses (methylprednisolone 30 mg/kg) resulted in more complications and was not associated with a lower mortality rate.4 On the other hand, a small study that included only patients with persistent ARDS (defined as ARDS lasting for more than 7 days) subsequently showed that oxygenation was significantly better and that fewer patients died while in the hospital with the use of methylprednisolone 2 mg/kg for 32 days.5
In view of these divergent findings, the ARDS Network decided to perform a study to help understand the role of corticosteroids in ARDS.
The Late Steroid Rescue Study (LaSRS)
STEINBERG KP, HUDSON LD, GOODMAN RB, ET AL; NATIONAL HEART, LUNG, AND BLOOD INSTITUTE ACUTE RESPIRATORY DISTRESS SYNDROME (ARDS) CLINICAL TRIALS NETWORK. EFFICACY AND SAFETY OF CORTICOSTEROIDS FOR PERSISTENT ACUTE RESPIRATORY DISTRESS SYNDROME. N ENGL J MED 2006; 354:1671–1684.
The Late Steroid Rescue Study (LaSRS),6 a double-blind, multicenter trial, randomly assigned 180 patients with persistent ARDS (defined as ongoing disease 7–28 days after its onset) to receive methylprednisolone or placebo for 21 days.
Methylprednisolone was given in an initial dose of 2 mg/kg of predicted body weight followed by a dose of 0.5 mg/kg every 6 hours for 14 days and then a dose of 0.5 mg/kg every 12 hours for 7 days, and then it was tapered over 2 to 4 days and discontinued. It could be discontinued if 21 days of treatment were completed or if the patient was able to breathe without assistance.
The primary end point was the mortality rate at 60 days. Secondary end points included the number of ventilator-free days, organ-failure-free days, and complications and the levels of biomarkers of inflammation.
No reduction in mortality rates with steroids
The mortality rates did not differ significantly in the corticosteroid group vs the placebo group at 60 days:
- 29.2% with methylprednisolone (95% confidence interval [CI] 20.8–39.4)
- 28.6% with placebo (95% CI 20.3–38.6, P = 1.0).
Mortality rates at 180 days were also similar between the groups:
- 31.5% with methylprednisolone (95% CI 22.8–41.7)
- 31.9% with placebo (95% CI 23.2–42.0, P = 1.0).
In patients randomized between 7 and 13 days after the onset of ARDS, the mortality rates were lower in the methylprednisolone group than in the placebo group but the differences were not statistically significant. The mortality rate in this subgroup was 27% vs 36% (P = .26) at 60 days and was 27% vs 39% (P = .14) at 180 days.
However, in patients randomized more than 14 days after the onset of ARDS, the mortality rate was significantly higher in the methylprednisolone group than in the placebo group at 60 days (35% vs 8%, P = .02) and at 180 days (44% vs 12%, P = .01).
Some benefit in secondary outcomes
At day 28, methylprednisolone was associated with:
- More ventilator-free days (11.2 ± 9.4 vs 6.8 ± 8.5, P < .001)
- More shock-free days (20.7 ± 8.9 vs 17.9 ± 10.2, P = .04)
- More ICU-free days (8.9 ± 8.2 vs 6.7 ± 7.8, P = .02).
Similarly, pulmonary physiologic indices were better with methylprednisolone, specifically:
- The ratio of Pao2 to the fraction of inspired oxygen at days 3, 4, and 14 (P < .05)
- Plateau pressure at days 4, 5, and 7 (P < .05)
- Static compliance at days 7 and 14 (P < .05).
In terms of side effects, methylprednisolone was associated with more events associated with myopathy or neuropathy (9 vs 0, P = .001), but there were no differences in the number of serious infections or in glycemic control.
Comments
Although other recent studies suggested that corticosteroid use may be associated with a reduction in mortality rates,7–9 LaSRS did not confirm this effect. Although the doses and length of therapy were similar in these studies, LaSRS was much larger and included patients from the ARDS Network.
Nevertheless, LaSRS was criticized because of strict exclusion criteria and poor enrollment (only 5% of eligible patients were included). Additionally, it was conducted over a period of time when some ICU practices varied significantly (eg, low vs high tidal volume ventilation, tight vs loose glucose control).
INTERRUPTING SEDATION DURING MECHANICAL VENTILATION
Key points
- Daily awakening of mechanically ventilated patients is safe.
- Daily interruption of sedation in mechanically ventilated patients is associated with a shorter length of mechanical ventilation.
Background
Sedatives are a central component of critical care. Continuous infusions of narcotics, benzodiazepines, and anesthetic agents are frequently used to promote comfort in patients receiving mechanical ventilation.
Despite its widespread use in the ICU, there is little evidence that such sedation improves outcomes. Observational and randomized trials10–12 have shown that patients who receive continuous infusions of sedatives need to be on mechanical ventilation longer than those who receive intermittent dosing. Additionally, an earlier randomized controlled trial13 showed that daily interruption of sedative drug infusions decreased the duration of mechanical ventilation by almost 50% and resulted in a reduction in the length of stay in the ICU.
Despite these findings, many ICU physicians remain skeptical of the value of daily interruption of sedative medications and question the safety of this practice.
The Awakening and Breathing Controlled (ABC) trial
GIRARD TD, KRESS JP, FUCHS BD, ET AL. EFFICACY AND SAFETY OF A PAIRED SEDATION AND VENTILATOR WEANING PROTOCOL FOR MECHANICALLY VENTILATED PATIENTS IN INTENSIVE CARE (AWAKENING AND BREATHING CONTROLLED TRIAL): A RANDOMISED CONTROLLED TRIAL. LANCET 2008; 371:126–134.
The Awakening and Breathing Controlled (ABC) trial14 was a multicenter, randomized controlled trial that included 336 patients who required at least 12 consecutive hours of mechanical ventilation. All patients had to be receiving patient-targeted sedation.
Those in the intervention group (n = 168) had their sedation interrupted every day, followed by a clinical assessment to determine whether they could be allowed to try breathing spontaneously. The control group (n = 168) also received a clinical assessment for a trial of spontaneous breathing, while their sedation was continued as usual.
In patients in the intervention group who failed the screening for a spontaneous breathing trial, the sedatives were resumed at half the previous dose. Criteria for failure on the spontaneous breathing trial included any of the following: anxiety, agitation, respiratory rate more than 35 breaths per minute for 5 minutes or longer, cardiac arrhythmia, oxygen saturation less than 88% for 5 minutes or longer, or two or more signs of respiratory distress, tachycardia, bradycardia, paradoxical breathing, accessory muscle use, diaphoresis, or marked dyspnea.
Interrupting sedation was superior
The combination of sedation interruption and a spontaneous breathing trial was superior to a spontaneous breathing trial alone. The mean number of ventilator-free days:
- 14.7 ± 0.9 with sedation interruption
- 11.6 ± 0.9 days with usual care (P = .02).
The median time to ICU discharge:
- 9.1 days with sedation interruption (interquartile range 5.1 to 17.8)
- 12.9 days with usual care (interquartile range 6.0 to 24.2, P = .01).
The mortality rate at 28 days:
- 28% with sedation interruption
- 35% with usual care (P = .21).
The mortality rate at 1 year:
- 44% with sedation interruption
- 58% with usual care (hazard ratio [HR] in the intervention group 0.68, 95% CI 0.50–0.92, P = .01).
Of note, patients in the intervention group had a higher rate of self-extubation (9.6% vs 3.6%, P = .03), but the rate of reintubation was similar between the groups (14% vs 13%, P = .47).
Comments
The addition of daily awakenings to spontaneous breathing trials results in a further reduction in the number of ICU days and increases the number of ventilator-free days.
Of note, the protocol allowed patients in the control group to undergo a spontaneous breathing trial while on sedatives (69% of the patients were receiving sedation at the time). Therefore, a bias effect in favor of the intervention group cannot be excluded. However, both groups had to meet criteria for readiness for spontaneous breathing.
The study demonstrates the safety of daily awakenings and confirms previous findings suggesting that a daily trial of spontaneous breathing results in better ICU outcomes.
GLUCOSE CONTROL IN THE ICU
Key points
- Although earlier studies suggested that intensive insulin therapy might be beneficial in critically ill patients, new findings show that strict glucose control can lead to complications without improving outcomes.
Background
A previous study15 found that intensive insulin therapy to maintain a blood glucose level between 80 and 110 mg/dL (compared with 180–200 mg/dL) reduced the mortality rate in surgical critical care patients. The mortality rate in the ICU was 4.6% with intensive insulin therapy vs 8.0% with conventional therapy (P < .04), and the effect was more robust for patients who remained longer than 5 days in the ICU (10.6% vs 20.2%).
Importantly, however, hypoglycemia (defined as blood glucose ≤ 40 mg/dL) occurred in 39 patients in the intensive-treatment group vs 6 patients in the conventional-treatment group.
The NICE-SUGAR trial
NICE-SUGAR STUDY INVESTIGATORS; FINFER S, CHITTOCK DR, SU SY, ET AL. INTENSIVE VERSUS CONVENTIONAL GLUCOSE CONTROL IN CRITICALLY ILL PATIENTS. N ENGL J MED 2009; 360:1283–1297.
The Normoglycemia in Intensive Care Evaluation-Survival Using Glucose Algorithm Regulation (NICE-SUGAR) trial16 randomized 6,104 patients in medical and surgical ICUs to receive either intensive glucose control (blood glucose 81–108 mg/dL) with insulin therapy or conventional glucose control (blood glucose < 180 mg/dL). In the conventional-control group, insulin was discontinued if the blood glucose level dropped below 144 mg/dL.
A higher mortality rate with intensive glucose control
As expected, the intensive-control group achieved lower blood glucose levels: 115 vs 144 mg/dL.
Nevertheless, intensive glucose control was associated with a higher incidence of severe hypoglycemia, defined as a blood glucose level lower than 40 mg/dL: 6.8% vs 0.5%.
More importantly, compared with conventional insulin therapy, intensive glucose control was associated with a higher 90-day mortality rate: 27.5% vs 24.9% (odds ratio 1.14, 95% CI 1.02–1.28). These findings were similar in the subgroup of surgical patients (24.4% vs 19.8%, odds ratio 1.31, 95% CI 1.07–1.61).
Comments
Of note, the conventional-control group had more patients who discontinued the treatment protocol prematurely. Additionally, more patients in this group received corticosteroids.
These results widely differ from those of a previous study by van den Berghe et al,15 which showed that tight glycemic control is associated with a survival benefit. The differences in outcomes are probably largely related to different patient populations, as van den Berghe et al included patients who had undergone cardiac surgery, who were more likely to benefit from strict blood glucose control.
The VISEP trial
BRUNKHORST FM, ENGEL C, BLOOS F, ET AL; GERMAN COMPETENCE NETWORK SEPSIS (SEPNET). INTENSIVE INSULIN THERAPY AND PENTASTARCH RESUSCITATION IN SEVERE SEPSIS. N ENGL J MED 2008; 358:125–139.
The Volume Substitution and Insulin Therapy in Severe Sepsis (VISEP) trial was a multicenter study designed to compare intensive insulin therapy (target blood glucose level 80–110 mg/dL) and conventional glucose control (target blood glucose level 180–200 mg/dL) in patients with severe sepsis.17 It also compared two fluids for volume resuscitation: 10% pentastarch vs modified Ringer's lactate. It included both medical and surgical patients.
Trial halted early for safety reasons
The mean morning blood glucose level was significantly lower in the intensive insulin group (112 vs 151 mg/dL).
Severe hypoglycemia (blood glucose ≤ 40 mg/dL) was more common in the group that received intensive insulin therapy (17% vs 4.1%, P < .001).
Mortality rates at 28 days did not differ significantly: 24.7% with intensive control vs 26.0% with conventional glucose control. The mortality rate at 90 days was 39.7% in the intensive therapy group and 35.4% in the conventional therapy group, but the difference was not statistically significant.
The intensive insulin arm of the trial was stopped after 488 patients were enrolled because of a higher rate of hypoglycemia (12.1% vs 2.1%) and of serious adverse events (10.9% vs 5.2%).
Additionally, the fluid resuscitation arm of the study was suspended at the first planned interim analysis because of a higher risk of organ failure in the 10% pentastarch group.
CORTICOSTEROID THERAPY IN SEPTIC SHOCK
Key points
- Corticosteroid therapy improves hemodynamic outcomes in patients with severe septic shock.
- Although meta-analyses suggest the mortality rate is lower with corticosteroid therapy, there is not enough evidence from randomized controlled trials to prove that the use of low-dose corticosteroids lowers the mortality rate in patients with septic shock.
- The corticotropin (ACTH) stimulation test should not be used to determine the need for corticosteroids in patients with septic shock.
Background
A previous multicenter study,18 performed in France, found that the use of corticosteroids in patients with septic shock resulted in lower rates of death at 28 days, in the ICU, and in the hospital and a shorter time to vasopressor withdrawal. Nevertheless, the beneficial effects were not observed in patients with adequate adrenal reserve (based on an ACTH stimulation test).
This study was criticized because of a high mortality rate in the placebo group.
The CORTICUS study
SPRUNG CL, ANNANE D, KEH D, ET AL; CORTICUS STUDY GROUP. HYDROCORTISONE THERAPY FOR PATIENTS WITH SEPTIC SHOCK. N ENGL J MED 2008; 358:111–124.
The Corticosteroid Therapy of Septic Shock (CORTICUS) study was a multicenter trial that randomly assigned 499 patients with septic shock to receive hydrocortisone (50 mg intravenously every 6 hours for 5 days, followed by a 6-day taper period) or placebo.19
Patients were eligible to be enrolled within 72 hours of onset of shock. Similar to previous studies, the CORTICUS trial classified patients on the basis of an ACTH stimulation test as having inadequate adrenal reserve (a cortisol increase of ≤ 9 μg/dL) or adequate adrenal reserve (a cortisol increase of > 9 μg/dL).
Faster reversal of shock with steroids
At baseline, the mean Simplified Acute Physiologic Score II (SAPS II) was 49 (the range of possible scores is 0 to 163; the higher the score the worse the organ dysfunction).
Hydrocortisone use resulted in a shorter duration of vasopressor use and a faster reversal of shock (3.3 days vs 5.8 days, P < .001).
This association was the same when patients were divided according to response to ACTH stimulation test. Time to reversal of shock in responders:
- 2.8 days with hydrocortisone
- 5.8 days with placebo (P < .001).
Time to reversal of shock in nonresponders:
- 3.9 days with hydrocortisone
- 6.0 days with placebo (P = .06).
Nevertheless, the treatment did not reduce the mortality rate at 28 days overall (34.3% vs 31.5% P = .51), or in the subgroups based on response to ACTH, or at any other time point. A post hoc analysis suggested that patients who had a systolic blood pressure of less than 90 mm Hg within 30 minutes of enrollment had a greater benefit in terms of mortality rate, but the effect was not statistically significant: the absolute difference was −11.2% (P = 0.28). Similarly, post hoc analyses also revealed a higher rate of death at 28 days in patients who received etomidate (Amidate) before randomization in both groups (P = .03).
Importantly, patients who received corticosteroids had a higher incidence of superinfections, including new episodes of sepsis or septic shock, with a combined odds ratio of 1.37 (95% CI 1.05–1.79).
Length of stay in the hospital or in the ICU was similar in patients who received corticosteroids and in those who received placebo. The ICU length of stay was 19 ± 31 days with hydrocortisone vs 18 ± 17 days with placebo (P = .51).
Comments
The CORTICUS trial showed that low-dose corticosteroid therapy results in faster reversal of shock in patients with severe septic shock. The hemodynamic benefits are present in all patients regardless of response to the ACTH stimulation test.
Nevertheless, contrary to previous findings,18 corticosteroid use was not associated with an improvement in mortality rates. Important differences exist between these two studies:
- The mortality rates in the placebo groups were significantly different (> 50% in the French study vs 30% in CORTICUS).
- The SAPS II scores were different in these two trials (55 vs 49), suggesting a greater severity of illness in the French study.
- The criteria for enrollment were different: the French study included patients who had a systolic blood pressure lower than 90 mm Hg for more than 1 hour despite fluid administration and vasopressor use, whereas the CORTICUS trial included patients who had a systolic blood pressure lower than 90 mm Hg for more than 1 hour despite fluid administration or vasopressor use.
- The time of enrollment was different: patients were enrolled much faster in the French study (within 8 hours) than in the CORTICUS trial (within 72 hours).
A recent meta-analysis of 17 randomized trials (including the CORTICUS study), found that, compared with those who received placebo, patients who received corticosteroids had a small reduction in the 28-day mortality rate (HR 0.84, 95% CI 0.71–1.00, P < .05).20 Of note, this meta-analysis has been criticized for possible publication bias and also for a large degree of heterogeneity in its results.21
VASOPRESSOR THERAPY IN SHOCK
Key points
- Vasopressin use in patients with severe septic shock is not associated with an improvement in mortality rates.
- Vasopressin should not be used as a first-line agent in patients with septic shock.
- Norepinephrine should be considered a first-line agent in patients with shock.
- Compared with norepinephrine, the use of dopamine in patients with shock is associated with similar mortality rates, although its use may result in a greater number of cardiac adverse events.
Background
Vasopressin gained popularity in critical care in the last 10 years because several small studies showed that adding it improves hemodynamics and results in a reduction in the doses of catecholamines in patients with refractory septic shock.22 Furthermore, the Surviving Sepsis Campaign guidelines recommended the use of vasopressin in patients who have refractory shock despite fluid resuscitation and the use of other “conventional” vasopressors.23
Despite these positive findings, it remained unknown if the use of vasopressin increases the survival rate in patients with septic shock.
The Vasopressin and Septic Shock Trial (VASST)
RUSSELL JA, WALLEY KR, SINGER J, ET AL; VASST INVESTIGATORS. VASOPRESSIN VERSUS NOREPINEPHRINE INFUSION IN PATIENTS WITH SEPTIC SHOCK. N ENGL J MED 2008; 358:877–887.
The Vasopressin and Septic Shock Trial (VASST)24 was a multicenter randomized, double-blind, controlled trial that included 778 patients with refractory septic shock. Refractory shock was defined as the lack of a response to a normal saline fluid bolus of 500 mL or the need for vasopressors (norepinephrine in doses of at least 5 μg/minute or its equivalent for 6 hours or more in the 24 hours before randomization).
Two subgroups were identified: those with severe septic shock (requiring norepinephrine in doses of 15 μg/minute or higher) and those with less-severe septic shock (needing norepinephrine in doses of 5 to 14 μg/minute). Patients with unstable coronary artery disease (acute myocardial infarction, angina) and severe congestive heart failure were excluded.
Patients were randomized to receive an intravenous infusion of vasopressin (0.01–0.03 U/minute) or norepinephrine (5–15 mg/minute) in addition to open-labeled vasopressors (excluding vasopressin). The primary outcome was the all-cause mortality rate at 28 days.
Results
At 28 days, fewer patients had died in the vasopressin group than in the norepinephrine group (35.4% vs 39.3%), but the difference was not statistically significant (P = .26). The trend was the same at 90 days (mortality rate 43.9% vs 49.6%, P = .11).
Subgroup analysis showed that in patients with less-severe septic shock, those who received vasopressin had a lower mortality rate at 28 days (26.5% vs 35.7%, P = .05; relative risk 0.74; 95% CI 0.55–1.01) and at 90 days (35.8% vs 46.1%, P = .04; relative risk 0.78, 95% CI 0.61–0.99).
There were no statistically significant differences in any of the other secondary outcomes or in serious adverse events.
Comments
The study has been criticized for several reasons:
- The mean arterial blood pressure at baseline before initiation of vasopressin was 72 mm Hg (and some argue that vasopressin was therefore not needed by the time it was started).
- The time from screening to infusion of the study drug was very long (12 hours).
- The observed mortality rate was lower than expected (37%).
Despite these considerations, the VASST trial showed that vasopressin is not associated with an increased number of adverse events in patients without active cardiovascular disease. The possible benefit in terms of the mortality rate in the subgroup of patients with less-severe septic shock requires further investigation.
Is dopamine equivalent to norepinephrine?
Previously, the Sepsis Occurrence in Acutely Ill Patients (SOAP) study, a multicenter, observational cohort study, found that dopamine use was associated with a higher all-cause mortality rate in the ICU compared with no dopamine.25 This finding had not been reproduced, as few well-designed studies had compared the effects of dopamine and norepinephrine.
The SOAP II study
DE BACKER D, BISTON P, DEVRIENDT J, ET AL; SOAP II INVESTIGATORS.. COMPARISON OF DOPAMINE AND NOREPINEPHRINE IN THE TREATMENT OF SHOCK. N ENGL J MED 2010; 362:779–789.
The SOAP II study,26 a multicenter, randomized trial, compared dopamine vs norepinephrine as first-line vasopressor therapy. In patients with refractory shock despite use of dopamine 20 μg/kg/minute or norepinephrine 0.19 μg/kg/minute, open-label norepinephrine, epinephrine, or vasopressin was added.
The primary outcome was the mortality rate at 28 days after randomization; secondary end points included the number of days without need for organ support and the occurrence of adverse events.
Results
A total of 1,679 patients were included; 858 were assigned to dopamine and 821 to norepinephrine. Most (1,044, 62%) of the patients had a diagnosis of septic shock.
No significant difference in mortality rates was noted at 28 days: 52.5% with dopamine vs 48.5% with norepinephrine (P = .10).
However, there were more arrhythmias in the patients treated with dopamine: 207 events (24.1%) vs 102 events (12.4%) (P < .001). The number of other adverse events such as renal failure, myocardial infarction, arterial occlusion, or skin necrosis was not different between the groups.
A subgroup analysis showed that dopamine was associated with more deaths at 28 days in patients with cardiogenic shock (P = .03) but not in patients with septic shock (P = .19) or with hypovolemic shock (P = .84).
Comments
The study was criticized because the patients may not have received adequate fluid resuscitation (the study considered adequate resuscitation to be equivalent to 1 L of crystalloids or 500 mL of colloids), as different degrees of volume depletion among patients make direct comparisons of vasopressor effects difficult.
Additionally, the study defined dopamine 20 μg/kg/minute as being equipotent with norepinephrine 0.19 μg/kg/minute. Comparisons of potency between drugs are difficult to establish, as there are no available data.
Nevertheless, this study further confirms previous findings suggesting that norepinephrine is not associated with more end-organ damage (such as renal failure or skin ischemia), and shows that dopamine may increase the number of adverse events, particularly in patients with cardiac disease.
- Shah MR, Hasselblad V, Stevenson LW, et al. Impact of the pulmonary artery catheter in critically ill patients: meta-analysis of randomized clinical trials. JAMA 2005; 294:1664–1670.
- National Heart, Lung, and Blood Institute Acute Respiratory Distress Syndrome (ARDS) Clinical Trials Network; Wiedemann HP, Wheeler AP, Bernard GR, et al. Comparison of two fluid-management strategies in acute lung injury. N Engl J Med 2006; 354:2564–2575.
- National Heart, Lung, and Blood Institute Acute Respiratory Distress Syndrome (ARDS) Clinical Trials Network; Wheeler AP, Bernard GR, Thompson BT, et al. Pulmonary-artery versus central venous catheter to guide treatment of acute lung injury. N Engl J Med 2006; 354:2213–2224.
- Bernard GR, Luce JM, Sprung CL, et al. High-dose corticosteroids in patients with the adult respiratory distress syndrome. N Engl J Med 1987; 317:1565–1570.
- Meduri GU, Headley AS, Golden E, et al. Effect of prolonged methylprednisolone therapy in unresolving acute respiratory distress syndrome: a randomized controlled trial. JAMA 1998; 280:159–165.
- Steinberg KP, Hudson LD, Goodman RB, et al; National Heart, Lung, and Blood Institute Acute Respiratory Distress Syndrome (ARDS) Clinical Trials Network. Efficacy and safety of corticosteroids for persistent acute respiratory distress syndrome. N Engl J Med 2006; 354:1671–1684.
- Meduri GU, Golden E, Freire AX, et al. Methylprednisolone infusion in early severe ARDS: results of a randomized controlled trial. Chest 2007; 131:954–963.
- Meduri GU, Golden E, Freire AX, et al. Methylprednisolone infusion in early severe ARDS results of a randomized controlled trial. 2007. Chest 2009; 136(suppl 5):e30.
- Annane D, Sébille V, Bellissant E; Ger-Inf-05 Study Group. Effect of low doses of corticosteroids in septic shock patients with or without early acute respiratory distress syndrome. Crit Care Med 2006; 34:22–30.
- Kollef MH, Levy NT, Ahrens TS, Schaiff R, Prentice D, Sherman G. The use of continuous i.v. sedation is associated with prolongation of mechanical ventilation. Chest 1998; 114:541–548.
- Carson SS, Kress JP, Rodgers JE, et al. A randomized trial of intermittent lorazepam versus propofol with daily interruption in mechanically ventilated patients. Crit Care Med 2006; 34:1326–1332.
- Brook AD, Ahrens TS, Schaiff R, et al. Effect of a nursing-implemented sedation protocol on the duration of mechanical ventilation. Crit Care Med 1999; 27:2609–2615.
- Kress JP, Pohlman AS, O’Connor MF, Hall JB. Daily interruption of sedative infusions in critically ill patients undergoing mechanical ventilation. N Engl J Med 2000; 342:1471–1477.
- Girard TD, Kress JP, Fuchs BD, et al. Efficacy and safety of a paired sedation and ventilator weaning protocol for mechanically ventilated patients in intensive care (Awakening and Breathing Controlled trial): a randomised controlled trial. Lancet 2008; 371:126–134.
- van den Berghe G, Wouters P, Weekers F, et al. Intensive insulin therapy in the critically ill patients. N Engl J Med 2001; 345:1359–1367.
- NICE-SUGAR Study Investigators; Finfer S, Chittock DR, Su SY, et al. Intensive versus conventional glucose control in critically ill patients. N Engl J Med 2009; 360:1283–1297.
- Brunkhorst FM, Engel C, Bloos F, et al; German Competence Network Sepsis (SepNet). Intensive insulin therapy and pentastarch resuscitation in severe sepsis. N Engl J Med 2008; 358:125–139.
- Annane D, Sébille V, Charpentier C, et al. Effect of treatment with low doses of hydrocortisone and fludrocortisone on mortality in patients with septic shock. JAMA 2002; 288:862–871.
- Sprung CL, Annane D, Keh D, et al; CORTICUS Study Group. Hydrocortisone therapy for patients with septic shock. N Engl J Med 2008; 358:111–124.
- Annane D, Bellissant E, Bollaert PE, et al. Corticosteroids in the treatment of severe sepsis and septic shock in adults: a systematic review. JAMA 2009; 301:2362–2375.
- Minneci PC, Deans KJ, Natanson C. Corticosteroid therapy for severe sepsis and septic shock [letter]. JAMA 2009; 302:16443–1644.
- Kampmeier TG, Rehberg S, Westphal M, Lange M. Vasopressin in sepsis and septic shock. Minerva Anestesiol 2010; 76:844–850.
- Dellinger RP, Levy MM, Carlet JM, et al; International Surviving Sepsis Campaign Guidelines Committee. Surviving Sepsis Campaign: international guidelines for management of severe sepsis and septic shock: 2008. Crit Care Med 2008; 36:296–327.
- Russell JA, Walley KR, Singer J, et al; VASST Investigators. Vasopressin versus norepinephrine infusion in patients with septic shock. N Engl J Med 2008; 358:877–887.
- Sakr Y, Reinhart K, Vincent JL, et al. Does dopamine administration in shock influence outcome? Results of the Sepsis Occurrence in Acutely Ill Patients (SOAP) Study. Crit Care Med 2006; 34:589–597.
- De Backer D, Biston P, Devriendt J, et al; SOAP II Investigators. Comparison of dopamine and norepinephrine in the treatment of shock. N Engl J Med 2010; 362:779–789.
We have seen significant growth in clinical research in critical care medicine in the last decade. Advances have been made in many important areas in this field; of these, advances in treating septic shock and acute respiratory distress syndrome (ARDS), and also in supportive therapies for critically ill patients (eg, sedatives, insulin), have perhaps received the most attention.
Of note, several once-established therapies in these areas have failed the test of time, as the result of evidence from more-recent clinical trials. For example, recent studies have shown that a pulmonary arterial catheter does not improve outcomes in patients with ARDS. Similarly, what used to be “optimal” fluid management in patients with ARDS is no longer considered appropriate.
In this review, we summarize eight major studies in critical care medicine published in the last 5 years, studies that have contributed to changes in our practice in the intensive care unit (ICU).
FLUID MANAGEMENT IN ARDS
Key points
- In patients with acute lung injury (ALI) and ARDS, fluid restriction is associated with better outcomes than a liberal fluid policy.
- A pulmonary arterial catheter is not necessary and, compared with a central venous catheter, may result in more complications in patients with ALI and ARDS.
Background
Fluid management practices in patients with ARDS have been extremely variable. Two different approaches are commonly used: the liberal or “wet” approach to optimize tissue perfusion and the “dry” approach, which focuses on reducing lung edema. Given that most deaths attributed to ARDS result from extrapulmonary organ failure, aggressive fluid restriction has been the less popular approach.
Additionally, although earlier studies and meta-analyses suggested that the use of a pulmonary arterial catheter was not associated with better outcomes in critically ill patients,1 controversy remained regarding the value of a pulmonary arterial catheter compared with a central venous catheter in guiding fluid management in patients with ARDS, and data were insufficient to prove one strategy better than the other.
The Fluids and Catheter Treatment Trial (FACTT)
NATIONAL HEART, LUNG, AND BLOOD INSTITUTE ACUTE RESPIRATORY DISTRESS SYNDROME (ARDS) CLINICAL TRIALS NETWORK; WIEDEMANN HP, WHEELER AP, BERNARD GR, ET AL. COMPARISON OF TWO FLUID-MANAGEMENT STRATEGIES IN ACUTE LUNG INJURY. N ENGL J MED 2006; 354:2564–2575.
NATIONAL HEART, LUNG, AND BLOOD INSTITUTE ACUTE RESPIRATORY DISTRESS SYNDROME (ARDS) CLINICAL TRIALS NETWORK; WHEELER AP, BERNARD GR, THOMPSON BT, ET AL. PULMONARY-ARTERY VERSUS CENTRAL VENOUS CATHETER TO GUIDE TREATMENT OF ACUTE LUNG INJURY. N ENGL J MED 2006; 354:2213–2224.
The Fluids and Catheter Treatment Trial (FACTT) compared two fluid strategies2 and also the utility of a pulmonary arterial catheter vs a central venous catheter3 in patients with ALI or ARDS.
This two-by-two factorial trial randomized 1,000 patients to be treated according to either a conservative (fluid-restrictive or “dry”) or a liberal (“wet”) fluid management strategy for 7 days. Additionally, they were randomly assigned to receive either a central venous catheter or a pulmonary arterial catheter. The trial thus had four treatment groups:
- Fluid-restricted and a central venous catheter, with a goal of keeping the central venous pressure below 4 mm Hg
- Fluid-restricted and a pulmonary arterial catheter: fluids were restricted and diuretics were given to keep the pulmonary artery occlusion pressure below 8 mm Hg
- Fluid-liberal and a central venous catheter: fluids were given to keep the central venous pressure between 10 and 14 mm Hg
- Fluid-liberal and a pulmonary arterial catheter: fluids were given to keep the pulmonary artery occlusion pressure between 14 and 18 mm Hg.
The primary end point was the mortality rate at 60 days. Secondary end points included the number of ventilator-free days and organ-failure-free days and parameters of lung physiology. All patients were managed with a low-tidal-volume strategy.
The ‘dry’ strategy was better
The cumulative fluid balance was −136 mL ± 491 mL in the “dry” group and 6,992 mL ± 502 mL in the “wet” group, a difference of more than 7 L (P < .0001). Of note, before randomization, the patients were already fluid-positive, with a mean total fluid balance of +2,700 mL).2
At 60 days, no statistically significant difference in mortality rate was seen between the fluid-management groups (25.5% in the dry group vs 28.4% in the wet group (P = .30). Nevertheless, patients in the dry group had better oxygenation indices and lung injury scores (including lower plateau airway pressure), resulting in more ventilator-free days (14.6 ± 0.5 vs 12.1 ± 0.5; P = .0002) and ICU-free days (13.4 ± 0.4 vs 11.2 ± 0.4; P = .0003).2
Although those in the dry-strategy group had a slightly lower cardiac index and mean arterial pressure, they did not have a higher incidence of shock.
More importantly, the dry group did not have a higher rate of nonpulmonary organ failure. Serum creatinine and blood urea nitrogen concentrations were slightly higher in this group, but this was not associated with a higher incidence of renal failure or the use of dialysis: 10% in the dry-strategy group vs 14% in the wet-strategy group; P = .0642).2
No advantage with a pulmonary arterial catheter
The mortality rate did not differ between the catheter groups. However, the patients who received a pulmonary arterial catheter stayed in the ICU 0.2 days longer and had twice as many nonfatal cardiac arrhythmias as those who received a central venous catheter.3
Comments
The liberal fluid-strategy group had fluid balances similar to those seen in previous National Institutes of Health ARDS Network trials in which fluid management was not controlled. This suggests that the liberal fluid strategy reflects usual clinical practice.
Although the goals used in this study (central venous pressure < 4 mm Hg or pulmonary artery occlusion pressure < 8 mm Hg) could be difficult to achieve in clinical practice, a conservative strategy of fluid management is preferred in patients with ALI or ARDS, given the benefits observed in this trial.
A pulmonary arterial catheter is not indicated to guide hemodynamic management of patients with ARDS.
CORTICOSTEROID USE IN ARDS
Key points
- In selected patients with ARDS, the prolonged use of corticosteroids may result in better oxygenation and a shorter duration of mechanical ventilation.
- Late use of corticosteroids in patients with ARDS (> 14 days after diagnosis) is not indicated and may increase the risk of death.
- The role of corticosteroids in early ARDS (< 7 days after diagnosis) remains controversial.
Background
Systemic corticosteroid therapy was commonly used in ARDS patients in the 1970s and 1980s. However, a single-center study published in the late 1980s showed that a corticosteroid in high doses (methylprednisolone 30 mg/kg) resulted in more complications and was not associated with a lower mortality rate.4 On the other hand, a small study that included only patients with persistent ARDS (defined as ARDS lasting for more than 7 days) subsequently showed that oxygenation was significantly better and that fewer patients died while in the hospital with the use of methylprednisolone 2 mg/kg for 32 days.5
In view of these divergent findings, the ARDS Network decided to perform a study to help understand the role of corticosteroids in ARDS.
The Late Steroid Rescue Study (LaSRS)
STEINBERG KP, HUDSON LD, GOODMAN RB, ET AL; NATIONAL HEART, LUNG, AND BLOOD INSTITUTE ACUTE RESPIRATORY DISTRESS SYNDROME (ARDS) CLINICAL TRIALS NETWORK. EFFICACY AND SAFETY OF CORTICOSTEROIDS FOR PERSISTENT ACUTE RESPIRATORY DISTRESS SYNDROME. N ENGL J MED 2006; 354:1671–1684.
The Late Steroid Rescue Study (LaSRS),6 a double-blind, multicenter trial, randomly assigned 180 patients with persistent ARDS (defined as ongoing disease 7–28 days after its onset) to receive methylprednisolone or placebo for 21 days.
Methylprednisolone was given in an initial dose of 2 mg/kg of predicted body weight followed by a dose of 0.5 mg/kg every 6 hours for 14 days and then a dose of 0.5 mg/kg every 12 hours for 7 days, and then it was tapered over 2 to 4 days and discontinued. It could be discontinued if 21 days of treatment were completed or if the patient was able to breathe without assistance.
The primary end point was the mortality rate at 60 days. Secondary end points included the number of ventilator-free days, organ-failure-free days, and complications and the levels of biomarkers of inflammation.
No reduction in mortality rates with steroids
The mortality rates did not differ significantly in the corticosteroid group vs the placebo group at 60 days:
- 29.2% with methylprednisolone (95% confidence interval [CI] 20.8–39.4)
- 28.6% with placebo (95% CI 20.3–38.6, P = 1.0).
Mortality rates at 180 days were also similar between the groups:
- 31.5% with methylprednisolone (95% CI 22.8–41.7)
- 31.9% with placebo (95% CI 23.2–42.0, P = 1.0).
In patients randomized between 7 and 13 days after the onset of ARDS, the mortality rates were lower in the methylprednisolone group than in the placebo group but the differences were not statistically significant. The mortality rate in this subgroup was 27% vs 36% (P = .26) at 60 days and was 27% vs 39% (P = .14) at 180 days.
However, in patients randomized more than 14 days after the onset of ARDS, the mortality rate was significantly higher in the methylprednisolone group than in the placebo group at 60 days (35% vs 8%, P = .02) and at 180 days (44% vs 12%, P = .01).
Some benefit in secondary outcomes
At day 28, methylprednisolone was associated with:
- More ventilator-free days (11.2 ± 9.4 vs 6.8 ± 8.5, P < .001)
- More shock-free days (20.7 ± 8.9 vs 17.9 ± 10.2, P = .04)
- More ICU-free days (8.9 ± 8.2 vs 6.7 ± 7.8, P = .02).
Similarly, pulmonary physiologic indices were better with methylprednisolone, specifically:
- The ratio of Pao2 to the fraction of inspired oxygen at days 3, 4, and 14 (P < .05)
- Plateau pressure at days 4, 5, and 7 (P < .05)
- Static compliance at days 7 and 14 (P < .05).
In terms of side effects, methylprednisolone was associated with more events associated with myopathy or neuropathy (9 vs 0, P = .001), but there were no differences in the number of serious infections or in glycemic control.
Comments
Although other recent studies suggested that corticosteroid use may be associated with a reduction in mortality rates,7–9 LaSRS did not confirm this effect. Although the doses and length of therapy were similar in these studies, LaSRS was much larger and included patients from the ARDS Network.
Nevertheless, LaSRS was criticized because of strict exclusion criteria and poor enrollment (only 5% of eligible patients were included). Additionally, it was conducted over a period of time when some ICU practices varied significantly (eg, low vs high tidal volume ventilation, tight vs loose glucose control).
INTERRUPTING SEDATION DURING MECHANICAL VENTILATION
Key points
- Daily awakening of mechanically ventilated patients is safe.
- Daily interruption of sedation in mechanically ventilated patients is associated with a shorter length of mechanical ventilation.
Background
Sedatives are a central component of critical care. Continuous infusions of narcotics, benzodiazepines, and anesthetic agents are frequently used to promote comfort in patients receiving mechanical ventilation.
Despite its widespread use in the ICU, there is little evidence that such sedation improves outcomes. Observational and randomized trials10–12 have shown that patients who receive continuous infusions of sedatives need to be on mechanical ventilation longer than those who receive intermittent dosing. Additionally, an earlier randomized controlled trial13 showed that daily interruption of sedative drug infusions decreased the duration of mechanical ventilation by almost 50% and resulted in a reduction in the length of stay in the ICU.
Despite these findings, many ICU physicians remain skeptical of the value of daily interruption of sedative medications and question the safety of this practice.
The Awakening and Breathing Controlled (ABC) trial
GIRARD TD, KRESS JP, FUCHS BD, ET AL. EFFICACY AND SAFETY OF A PAIRED SEDATION AND VENTILATOR WEANING PROTOCOL FOR MECHANICALLY VENTILATED PATIENTS IN INTENSIVE CARE (AWAKENING AND BREATHING CONTROLLED TRIAL): A RANDOMISED CONTROLLED TRIAL. LANCET 2008; 371:126–134.
The Awakening and Breathing Controlled (ABC) trial14 was a multicenter, randomized controlled trial that included 336 patients who required at least 12 consecutive hours of mechanical ventilation. All patients had to be receiving patient-targeted sedation.
Those in the intervention group (n = 168) had their sedation interrupted every day, followed by a clinical assessment to determine whether they could be allowed to try breathing spontaneously. The control group (n = 168) also received a clinical assessment for a trial of spontaneous breathing, while their sedation was continued as usual.
In patients in the intervention group who failed the screening for a spontaneous breathing trial, the sedatives were resumed at half the previous dose. Criteria for failure on the spontaneous breathing trial included any of the following: anxiety, agitation, respiratory rate more than 35 breaths per minute for 5 minutes or longer, cardiac arrhythmia, oxygen saturation less than 88% for 5 minutes or longer, or two or more signs of respiratory distress, tachycardia, bradycardia, paradoxical breathing, accessory muscle use, diaphoresis, or marked dyspnea.
Interrupting sedation was superior
The combination of sedation interruption and a spontaneous breathing trial was superior to a spontaneous breathing trial alone. The mean number of ventilator-free days:
- 14.7 ± 0.9 with sedation interruption
- 11.6 ± 0.9 days with usual care (P = .02).
The median time to ICU discharge:
- 9.1 days with sedation interruption (interquartile range 5.1 to 17.8)
- 12.9 days with usual care (interquartile range 6.0 to 24.2, P = .01).
The mortality rate at 28 days:
- 28% with sedation interruption
- 35% with usual care (P = .21).
The mortality rate at 1 year:
- 44% with sedation interruption
- 58% with usual care (hazard ratio [HR] in the intervention group 0.68, 95% CI 0.50–0.92, P = .01).
Of note, patients in the intervention group had a higher rate of self-extubation (9.6% vs 3.6%, P = .03), but the rate of reintubation was similar between the groups (14% vs 13%, P = .47).
Comments
The addition of daily awakenings to spontaneous breathing trials results in a further reduction in the number of ICU days and increases the number of ventilator-free days.
Of note, the protocol allowed patients in the control group to undergo a spontaneous breathing trial while on sedatives (69% of the patients were receiving sedation at the time). Therefore, a bias effect in favor of the intervention group cannot be excluded. However, both groups had to meet criteria for readiness for spontaneous breathing.
The study demonstrates the safety of daily awakenings and confirms previous findings suggesting that a daily trial of spontaneous breathing results in better ICU outcomes.
GLUCOSE CONTROL IN THE ICU
Key points
- Although earlier studies suggested that intensive insulin therapy might be beneficial in critically ill patients, new findings show that strict glucose control can lead to complications without improving outcomes.
Background
A previous study15 found that intensive insulin therapy to maintain a blood glucose level between 80 and 110 mg/dL (compared with 180–200 mg/dL) reduced the mortality rate in surgical critical care patients. The mortality rate in the ICU was 4.6% with intensive insulin therapy vs 8.0% with conventional therapy (P < .04), and the effect was more robust for patients who remained longer than 5 days in the ICU (10.6% vs 20.2%).
Importantly, however, hypoglycemia (defined as blood glucose ≤ 40 mg/dL) occurred in 39 patients in the intensive-treatment group vs 6 patients in the conventional-treatment group.
The NICE-SUGAR trial
NICE-SUGAR STUDY INVESTIGATORS; FINFER S, CHITTOCK DR, SU SY, ET AL. INTENSIVE VERSUS CONVENTIONAL GLUCOSE CONTROL IN CRITICALLY ILL PATIENTS. N ENGL J MED 2009; 360:1283–1297.
The Normoglycemia in Intensive Care Evaluation-Survival Using Glucose Algorithm Regulation (NICE-SUGAR) trial16 randomized 6,104 patients in medical and surgical ICUs to receive either intensive glucose control (blood glucose 81–108 mg/dL) with insulin therapy or conventional glucose control (blood glucose < 180 mg/dL). In the conventional-control group, insulin was discontinued if the blood glucose level dropped below 144 mg/dL.
A higher mortality rate with intensive glucose control
As expected, the intensive-control group achieved lower blood glucose levels: 115 vs 144 mg/dL.
Nevertheless, intensive glucose control was associated with a higher incidence of severe hypoglycemia, defined as a blood glucose level lower than 40 mg/dL: 6.8% vs 0.5%.
More importantly, compared with conventional insulin therapy, intensive glucose control was associated with a higher 90-day mortality rate: 27.5% vs 24.9% (odds ratio 1.14, 95% CI 1.02–1.28). These findings were similar in the subgroup of surgical patients (24.4% vs 19.8%, odds ratio 1.31, 95% CI 1.07–1.61).
Comments
Of note, the conventional-control group had more patients who discontinued the treatment protocol prematurely. Additionally, more patients in this group received corticosteroids.
These results widely differ from those of a previous study by van den Berghe et al,15 which showed that tight glycemic control is associated with a survival benefit. The differences in outcomes are probably largely related to different patient populations, as van den Berghe et al included patients who had undergone cardiac surgery, who were more likely to benefit from strict blood glucose control.
The VISEP trial
BRUNKHORST FM, ENGEL C, BLOOS F, ET AL; GERMAN COMPETENCE NETWORK SEPSIS (SEPNET). INTENSIVE INSULIN THERAPY AND PENTASTARCH RESUSCITATION IN SEVERE SEPSIS. N ENGL J MED 2008; 358:125–139.
The Volume Substitution and Insulin Therapy in Severe Sepsis (VISEP) trial was a multicenter study designed to compare intensive insulin therapy (target blood glucose level 80–110 mg/dL) and conventional glucose control (target blood glucose level 180–200 mg/dL) in patients with severe sepsis.17 It also compared two fluids for volume resuscitation: 10% pentastarch vs modified Ringer's lactate. It included both medical and surgical patients.
Trial halted early for safety reasons
The mean morning blood glucose level was significantly lower in the intensive insulin group (112 vs 151 mg/dL).
Severe hypoglycemia (blood glucose ≤ 40 mg/dL) was more common in the group that received intensive insulin therapy (17% vs 4.1%, P < .001).
Mortality rates at 28 days did not differ significantly: 24.7% with intensive control vs 26.0% with conventional glucose control. The mortality rate at 90 days was 39.7% in the intensive therapy group and 35.4% in the conventional therapy group, but the difference was not statistically significant.
The intensive insulin arm of the trial was stopped after 488 patients were enrolled because of a higher rate of hypoglycemia (12.1% vs 2.1%) and of serious adverse events (10.9% vs 5.2%).
Additionally, the fluid resuscitation arm of the study was suspended at the first planned interim analysis because of a higher risk of organ failure in the 10% pentastarch group.
CORTICOSTEROID THERAPY IN SEPTIC SHOCK
Key points
- Corticosteroid therapy improves hemodynamic outcomes in patients with severe septic shock.
- Although meta-analyses suggest the mortality rate is lower with corticosteroid therapy, there is not enough evidence from randomized controlled trials to prove that the use of low-dose corticosteroids lowers the mortality rate in patients with septic shock.
- The corticotropin (ACTH) stimulation test should not be used to determine the need for corticosteroids in patients with septic shock.
Background
A previous multicenter study,18 performed in France, found that the use of corticosteroids in patients with septic shock resulted in lower rates of death at 28 days, in the ICU, and in the hospital and a shorter time to vasopressor withdrawal. Nevertheless, the beneficial effects were not observed in patients with adequate adrenal reserve (based on an ACTH stimulation test).
This study was criticized because of a high mortality rate in the placebo group.
The CORTICUS study
SPRUNG CL, ANNANE D, KEH D, ET AL; CORTICUS STUDY GROUP. HYDROCORTISONE THERAPY FOR PATIENTS WITH SEPTIC SHOCK. N ENGL J MED 2008; 358:111–124.
The Corticosteroid Therapy of Septic Shock (CORTICUS) study was a multicenter trial that randomly assigned 499 patients with septic shock to receive hydrocortisone (50 mg intravenously every 6 hours for 5 days, followed by a 6-day taper period) or placebo.19
Patients were eligible to be enrolled within 72 hours of onset of shock. Similar to previous studies, the CORTICUS trial classified patients on the basis of an ACTH stimulation test as having inadequate adrenal reserve (a cortisol increase of ≤ 9 μg/dL) or adequate adrenal reserve (a cortisol increase of > 9 μg/dL).
Faster reversal of shock with steroids
At baseline, the mean Simplified Acute Physiologic Score II (SAPS II) was 49 (the range of possible scores is 0 to 163; the higher the score the worse the organ dysfunction).
Hydrocortisone use resulted in a shorter duration of vasopressor use and a faster reversal of shock (3.3 days vs 5.8 days, P < .001).
This association was the same when patients were divided according to response to ACTH stimulation test. Time to reversal of shock in responders:
- 2.8 days with hydrocortisone
- 5.8 days with placebo (P < .001).
Time to reversal of shock in nonresponders:
- 3.9 days with hydrocortisone
- 6.0 days with placebo (P = .06).
Nevertheless, the treatment did not reduce the mortality rate at 28 days overall (34.3% vs 31.5% P = .51), or in the subgroups based on response to ACTH, or at any other time point. A post hoc analysis suggested that patients who had a systolic blood pressure of less than 90 mm Hg within 30 minutes of enrollment had a greater benefit in terms of mortality rate, but the effect was not statistically significant: the absolute difference was −11.2% (P = 0.28). Similarly, post hoc analyses also revealed a higher rate of death at 28 days in patients who received etomidate (Amidate) before randomization in both groups (P = .03).
Importantly, patients who received corticosteroids had a higher incidence of superinfections, including new episodes of sepsis or septic shock, with a combined odds ratio of 1.37 (95% CI 1.05–1.79).
Length of stay in the hospital or in the ICU was similar in patients who received corticosteroids and in those who received placebo. The ICU length of stay was 19 ± 31 days with hydrocortisone vs 18 ± 17 days with placebo (P = .51).
Comments
The CORTICUS trial showed that low-dose corticosteroid therapy results in faster reversal of shock in patients with severe septic shock. The hemodynamic benefits are present in all patients regardless of response to the ACTH stimulation test.
Nevertheless, contrary to previous findings,18 corticosteroid use was not associated with an improvement in mortality rates. Important differences exist between these two studies:
- The mortality rates in the placebo groups were significantly different (> 50% in the French study vs 30% in CORTICUS).
- The SAPS II scores were different in these two trials (55 vs 49), suggesting a greater severity of illness in the French study.
- The criteria for enrollment were different: the French study included patients who had a systolic blood pressure lower than 90 mm Hg for more than 1 hour despite fluid administration and vasopressor use, whereas the CORTICUS trial included patients who had a systolic blood pressure lower than 90 mm Hg for more than 1 hour despite fluid administration or vasopressor use.
- The time of enrollment was different: patients were enrolled much faster in the French study (within 8 hours) than in the CORTICUS trial (within 72 hours).
A recent meta-analysis of 17 randomized trials (including the CORTICUS study), found that, compared with those who received placebo, patients who received corticosteroids had a small reduction in the 28-day mortality rate (HR 0.84, 95% CI 0.71–1.00, P < .05).20 Of note, this meta-analysis has been criticized for possible publication bias and also for a large degree of heterogeneity in its results.21
VASOPRESSOR THERAPY IN SHOCK
Key points
- Vasopressin use in patients with severe septic shock is not associated with an improvement in mortality rates.
- Vasopressin should not be used as a first-line agent in patients with septic shock.
- Norepinephrine should be considered a first-line agent in patients with shock.
- Compared with norepinephrine, the use of dopamine in patients with shock is associated with similar mortality rates, although its use may result in a greater number of cardiac adverse events.
Background
Vasopressin gained popularity in critical care in the last 10 years because several small studies showed that adding it improves hemodynamics and results in a reduction in the doses of catecholamines in patients with refractory septic shock.22 Furthermore, the Surviving Sepsis Campaign guidelines recommended the use of vasopressin in patients who have refractory shock despite fluid resuscitation and the use of other “conventional” vasopressors.23
Despite these positive findings, it remained unknown if the use of vasopressin increases the survival rate in patients with septic shock.
The Vasopressin and Septic Shock Trial (VASST)
RUSSELL JA, WALLEY KR, SINGER J, ET AL; VASST INVESTIGATORS. VASOPRESSIN VERSUS NOREPINEPHRINE INFUSION IN PATIENTS WITH SEPTIC SHOCK. N ENGL J MED 2008; 358:877–887.
The Vasopressin and Septic Shock Trial (VASST)24 was a multicenter randomized, double-blind, controlled trial that included 778 patients with refractory septic shock. Refractory shock was defined as the lack of a response to a normal saline fluid bolus of 500 mL or the need for vasopressors (norepinephrine in doses of at least 5 μg/minute or its equivalent for 6 hours or more in the 24 hours before randomization).
Two subgroups were identified: those with severe septic shock (requiring norepinephrine in doses of 15 μg/minute or higher) and those with less-severe septic shock (needing norepinephrine in doses of 5 to 14 μg/minute). Patients with unstable coronary artery disease (acute myocardial infarction, angina) and severe congestive heart failure were excluded.
Patients were randomized to receive an intravenous infusion of vasopressin (0.01–0.03 U/minute) or norepinephrine (5–15 mg/minute) in addition to open-labeled vasopressors (excluding vasopressin). The primary outcome was the all-cause mortality rate at 28 days.
Results
At 28 days, fewer patients had died in the vasopressin group than in the norepinephrine group (35.4% vs 39.3%), but the difference was not statistically significant (P = .26). The trend was the same at 90 days (mortality rate 43.9% vs 49.6%, P = .11).
Subgroup analysis showed that in patients with less-severe septic shock, those who received vasopressin had a lower mortality rate at 28 days (26.5% vs 35.7%, P = .05; relative risk 0.74; 95% CI 0.55–1.01) and at 90 days (35.8% vs 46.1%, P = .04; relative risk 0.78, 95% CI 0.61–0.99).
There were no statistically significant differences in any of the other secondary outcomes or in serious adverse events.
Comments
The study has been criticized for several reasons:
- The mean arterial blood pressure at baseline before initiation of vasopressin was 72 mm Hg (and some argue that vasopressin was therefore not needed by the time it was started).
- The time from screening to infusion of the study drug was very long (12 hours).
- The observed mortality rate was lower than expected (37%).
Despite these considerations, the VASST trial showed that vasopressin is not associated with an increased number of adverse events in patients without active cardiovascular disease. The possible benefit in terms of the mortality rate in the subgroup of patients with less-severe septic shock requires further investigation.
Is dopamine equivalent to norepinephrine?
Previously, the Sepsis Occurrence in Acutely Ill Patients (SOAP) study, a multicenter, observational cohort study, found that dopamine use was associated with a higher all-cause mortality rate in the ICU compared with no dopamine.25 This finding had not been reproduced, as few well-designed studies had compared the effects of dopamine and norepinephrine.
The SOAP II study
DE BACKER D, BISTON P, DEVRIENDT J, ET AL; SOAP II INVESTIGATORS.. COMPARISON OF DOPAMINE AND NOREPINEPHRINE IN THE TREATMENT OF SHOCK. N ENGL J MED 2010; 362:779–789.
The SOAP II study,26 a multicenter, randomized trial, compared dopamine vs norepinephrine as first-line vasopressor therapy. In patients with refractory shock despite use of dopamine 20 μg/kg/minute or norepinephrine 0.19 μg/kg/minute, open-label norepinephrine, epinephrine, or vasopressin was added.
The primary outcome was the mortality rate at 28 days after randomization; secondary end points included the number of days without need for organ support and the occurrence of adverse events.
Results
A total of 1,679 patients were included; 858 were assigned to dopamine and 821 to norepinephrine. Most (1,044, 62%) of the patients had a diagnosis of septic shock.
No significant difference in mortality rates was noted at 28 days: 52.5% with dopamine vs 48.5% with norepinephrine (P = .10).
However, there were more arrhythmias in the patients treated with dopamine: 207 events (24.1%) vs 102 events (12.4%) (P < .001). The number of other adverse events such as renal failure, myocardial infarction, arterial occlusion, or skin necrosis was not different between the groups.
A subgroup analysis showed that dopamine was associated with more deaths at 28 days in patients with cardiogenic shock (P = .03) but not in patients with septic shock (P = .19) or with hypovolemic shock (P = .84).
Comments
The study was criticized because the patients may not have received adequate fluid resuscitation (the study considered adequate resuscitation to be equivalent to 1 L of crystalloids or 500 mL of colloids), as different degrees of volume depletion among patients make direct comparisons of vasopressor effects difficult.
Additionally, the study defined dopamine 20 μg/kg/minute as being equipotent with norepinephrine 0.19 μg/kg/minute. Comparisons of potency between drugs are difficult to establish, as there are no available data.
Nevertheless, this study further confirms previous findings suggesting that norepinephrine is not associated with more end-organ damage (such as renal failure or skin ischemia), and shows that dopamine may increase the number of adverse events, particularly in patients with cardiac disease.
We have seen significant growth in clinical research in critical care medicine in the last decade. Advances have been made in many important areas in this field; of these, advances in treating septic shock and acute respiratory distress syndrome (ARDS), and also in supportive therapies for critically ill patients (eg, sedatives, insulin), have perhaps received the most attention.
Of note, several once-established therapies in these areas have failed the test of time, as the result of evidence from more-recent clinical trials. For example, recent studies have shown that a pulmonary arterial catheter does not improve outcomes in patients with ARDS. Similarly, what used to be “optimal” fluid management in patients with ARDS is no longer considered appropriate.
In this review, we summarize eight major studies in critical care medicine published in the last 5 years, studies that have contributed to changes in our practice in the intensive care unit (ICU).
FLUID MANAGEMENT IN ARDS
Key points
- In patients with acute lung injury (ALI) and ARDS, fluid restriction is associated with better outcomes than a liberal fluid policy.
- A pulmonary arterial catheter is not necessary and, compared with a central venous catheter, may result in more complications in patients with ALI and ARDS.
Background
Fluid management practices in patients with ARDS have been extremely variable. Two different approaches are commonly used: the liberal or “wet” approach to optimize tissue perfusion and the “dry” approach, which focuses on reducing lung edema. Given that most deaths attributed to ARDS result from extrapulmonary organ failure, aggressive fluid restriction has been the less popular approach.
Additionally, although earlier studies and meta-analyses suggested that the use of a pulmonary arterial catheter was not associated with better outcomes in critically ill patients,1 controversy remained regarding the value of a pulmonary arterial catheter compared with a central venous catheter in guiding fluid management in patients with ARDS, and data were insufficient to prove one strategy better than the other.
The Fluids and Catheter Treatment Trial (FACTT)
NATIONAL HEART, LUNG, AND BLOOD INSTITUTE ACUTE RESPIRATORY DISTRESS SYNDROME (ARDS) CLINICAL TRIALS NETWORK; WIEDEMANN HP, WHEELER AP, BERNARD GR, ET AL. COMPARISON OF TWO FLUID-MANAGEMENT STRATEGIES IN ACUTE LUNG INJURY. N ENGL J MED 2006; 354:2564–2575.
NATIONAL HEART, LUNG, AND BLOOD INSTITUTE ACUTE RESPIRATORY DISTRESS SYNDROME (ARDS) CLINICAL TRIALS NETWORK; WHEELER AP, BERNARD GR, THOMPSON BT, ET AL. PULMONARY-ARTERY VERSUS CENTRAL VENOUS CATHETER TO GUIDE TREATMENT OF ACUTE LUNG INJURY. N ENGL J MED 2006; 354:2213–2224.
The Fluids and Catheter Treatment Trial (FACTT) compared two fluid strategies2 and also the utility of a pulmonary arterial catheter vs a central venous catheter3 in patients with ALI or ARDS.
This two-by-two factorial trial randomized 1,000 patients to be treated according to either a conservative (fluid-restrictive or “dry”) or a liberal (“wet”) fluid management strategy for 7 days. Additionally, they were randomly assigned to receive either a central venous catheter or a pulmonary arterial catheter. The trial thus had four treatment groups:
- Fluid-restricted and a central venous catheter, with a goal of keeping the central venous pressure below 4 mm Hg
- Fluid-restricted and a pulmonary arterial catheter: fluids were restricted and diuretics were given to keep the pulmonary artery occlusion pressure below 8 mm Hg
- Fluid-liberal and a central venous catheter: fluids were given to keep the central venous pressure between 10 and 14 mm Hg
- Fluid-liberal and a pulmonary arterial catheter: fluids were given to keep the pulmonary artery occlusion pressure between 14 and 18 mm Hg.
The primary end point was the mortality rate at 60 days. Secondary end points included the number of ventilator-free days and organ-failure-free days and parameters of lung physiology. All patients were managed with a low-tidal-volume strategy.
The ‘dry’ strategy was better
The cumulative fluid balance was −136 mL ± 491 mL in the “dry” group and 6,992 mL ± 502 mL in the “wet” group, a difference of more than 7 L (P < .0001). Of note, before randomization, the patients were already fluid-positive, with a mean total fluid balance of +2,700 mL).2
At 60 days, no statistically significant difference in mortality rate was seen between the fluid-management groups (25.5% in the dry group vs 28.4% in the wet group (P = .30). Nevertheless, patients in the dry group had better oxygenation indices and lung injury scores (including lower plateau airway pressure), resulting in more ventilator-free days (14.6 ± 0.5 vs 12.1 ± 0.5; P = .0002) and ICU-free days (13.4 ± 0.4 vs 11.2 ± 0.4; P = .0003).2
Although those in the dry-strategy group had a slightly lower cardiac index and mean arterial pressure, they did not have a higher incidence of shock.
More importantly, the dry group did not have a higher rate of nonpulmonary organ failure. Serum creatinine and blood urea nitrogen concentrations were slightly higher in this group, but this was not associated with a higher incidence of renal failure or the use of dialysis: 10% in the dry-strategy group vs 14% in the wet-strategy group; P = .0642).2
No advantage with a pulmonary arterial catheter
The mortality rate did not differ between the catheter groups. However, the patients who received a pulmonary arterial catheter stayed in the ICU 0.2 days longer and had twice as many nonfatal cardiac arrhythmias as those who received a central venous catheter.3
Comments
The liberal fluid-strategy group had fluid balances similar to those seen in previous National Institutes of Health ARDS Network trials in which fluid management was not controlled. This suggests that the liberal fluid strategy reflects usual clinical practice.
Although the goals used in this study (central venous pressure < 4 mm Hg or pulmonary artery occlusion pressure < 8 mm Hg) could be difficult to achieve in clinical practice, a conservative strategy of fluid management is preferred in patients with ALI or ARDS, given the benefits observed in this trial.
A pulmonary arterial catheter is not indicated to guide hemodynamic management of patients with ARDS.
CORTICOSTEROID USE IN ARDS
Key points
- In selected patients with ARDS, the prolonged use of corticosteroids may result in better oxygenation and a shorter duration of mechanical ventilation.
- Late use of corticosteroids in patients with ARDS (> 14 days after diagnosis) is not indicated and may increase the risk of death.
- The role of corticosteroids in early ARDS (< 7 days after diagnosis) remains controversial.
Background
Systemic corticosteroid therapy was commonly used in ARDS patients in the 1970s and 1980s. However, a single-center study published in the late 1980s showed that a corticosteroid in high doses (methylprednisolone 30 mg/kg) resulted in more complications and was not associated with a lower mortality rate.4 On the other hand, a small study that included only patients with persistent ARDS (defined as ARDS lasting for more than 7 days) subsequently showed that oxygenation was significantly better and that fewer patients died while in the hospital with the use of methylprednisolone 2 mg/kg for 32 days.5
In view of these divergent findings, the ARDS Network decided to perform a study to help understand the role of corticosteroids in ARDS.
The Late Steroid Rescue Study (LaSRS)
STEINBERG KP, HUDSON LD, GOODMAN RB, ET AL; NATIONAL HEART, LUNG, AND BLOOD INSTITUTE ACUTE RESPIRATORY DISTRESS SYNDROME (ARDS) CLINICAL TRIALS NETWORK. EFFICACY AND SAFETY OF CORTICOSTEROIDS FOR PERSISTENT ACUTE RESPIRATORY DISTRESS SYNDROME. N ENGL J MED 2006; 354:1671–1684.
The Late Steroid Rescue Study (LaSRS),6 a double-blind, multicenter trial, randomly assigned 180 patients with persistent ARDS (defined as ongoing disease 7–28 days after its onset) to receive methylprednisolone or placebo for 21 days.
Methylprednisolone was given in an initial dose of 2 mg/kg of predicted body weight followed by a dose of 0.5 mg/kg every 6 hours for 14 days and then a dose of 0.5 mg/kg every 12 hours for 7 days, and then it was tapered over 2 to 4 days and discontinued. It could be discontinued if 21 days of treatment were completed or if the patient was able to breathe without assistance.
The primary end point was the mortality rate at 60 days. Secondary end points included the number of ventilator-free days, organ-failure-free days, and complications and the levels of biomarkers of inflammation.
No reduction in mortality rates with steroids
The mortality rates did not differ significantly in the corticosteroid group vs the placebo group at 60 days:
- 29.2% with methylprednisolone (95% confidence interval [CI] 20.8–39.4)
- 28.6% with placebo (95% CI 20.3–38.6, P = 1.0).
Mortality rates at 180 days were also similar between the groups:
- 31.5% with methylprednisolone (95% CI 22.8–41.7)
- 31.9% with placebo (95% CI 23.2–42.0, P = 1.0).
In patients randomized between 7 and 13 days after the onset of ARDS, the mortality rates were lower in the methylprednisolone group than in the placebo group but the differences were not statistically significant. The mortality rate in this subgroup was 27% vs 36% (P = .26) at 60 days and was 27% vs 39% (P = .14) at 180 days.
However, in patients randomized more than 14 days after the onset of ARDS, the mortality rate was significantly higher in the methylprednisolone group than in the placebo group at 60 days (35% vs 8%, P = .02) and at 180 days (44% vs 12%, P = .01).
Some benefit in secondary outcomes
At day 28, methylprednisolone was associated with:
- More ventilator-free days (11.2 ± 9.4 vs 6.8 ± 8.5, P < .001)
- More shock-free days (20.7 ± 8.9 vs 17.9 ± 10.2, P = .04)
- More ICU-free days (8.9 ± 8.2 vs 6.7 ± 7.8, P = .02).
Similarly, pulmonary physiologic indices were better with methylprednisolone, specifically:
- The ratio of Pao2 to the fraction of inspired oxygen at days 3, 4, and 14 (P < .05)
- Plateau pressure at days 4, 5, and 7 (P < .05)
- Static compliance at days 7 and 14 (P < .05).
In terms of side effects, methylprednisolone was associated with more events associated with myopathy or neuropathy (9 vs 0, P = .001), but there were no differences in the number of serious infections or in glycemic control.
Comments
Although other recent studies suggested that corticosteroid use may be associated with a reduction in mortality rates,7–9 LaSRS did not confirm this effect. Although the doses and length of therapy were similar in these studies, LaSRS was much larger and included patients from the ARDS Network.
Nevertheless, LaSRS was criticized because of strict exclusion criteria and poor enrollment (only 5% of eligible patients were included). Additionally, it was conducted over a period of time when some ICU practices varied significantly (eg, low vs high tidal volume ventilation, tight vs loose glucose control).
INTERRUPTING SEDATION DURING MECHANICAL VENTILATION
Key points
- Daily awakening of mechanically ventilated patients is safe.
- Daily interruption of sedation in mechanically ventilated patients is associated with a shorter length of mechanical ventilation.
Background
Sedatives are a central component of critical care. Continuous infusions of narcotics, benzodiazepines, and anesthetic agents are frequently used to promote comfort in patients receiving mechanical ventilation.
Despite its widespread use in the ICU, there is little evidence that such sedation improves outcomes. Observational and randomized trials10–12 have shown that patients who receive continuous infusions of sedatives need to be on mechanical ventilation longer than those who receive intermittent dosing. Additionally, an earlier randomized controlled trial13 showed that daily interruption of sedative drug infusions decreased the duration of mechanical ventilation by almost 50% and resulted in a reduction in the length of stay in the ICU.
Despite these findings, many ICU physicians remain skeptical of the value of daily interruption of sedative medications and question the safety of this practice.
The Awakening and Breathing Controlled (ABC) trial
GIRARD TD, KRESS JP, FUCHS BD, ET AL. EFFICACY AND SAFETY OF A PAIRED SEDATION AND VENTILATOR WEANING PROTOCOL FOR MECHANICALLY VENTILATED PATIENTS IN INTENSIVE CARE (AWAKENING AND BREATHING CONTROLLED TRIAL): A RANDOMISED CONTROLLED TRIAL. LANCET 2008; 371:126–134.
The Awakening and Breathing Controlled (ABC) trial14 was a multicenter, randomized controlled trial that included 336 patients who required at least 12 consecutive hours of mechanical ventilation. All patients had to be receiving patient-targeted sedation.
Those in the intervention group (n = 168) had their sedation interrupted every day, followed by a clinical assessment to determine whether they could be allowed to try breathing spontaneously. The control group (n = 168) also received a clinical assessment for a trial of spontaneous breathing, while their sedation was continued as usual.
In patients in the intervention group who failed the screening for a spontaneous breathing trial, the sedatives were resumed at half the previous dose. Criteria for failure on the spontaneous breathing trial included any of the following: anxiety, agitation, respiratory rate more than 35 breaths per minute for 5 minutes or longer, cardiac arrhythmia, oxygen saturation less than 88% for 5 minutes or longer, or two or more signs of respiratory distress, tachycardia, bradycardia, paradoxical breathing, accessory muscle use, diaphoresis, or marked dyspnea.
Interrupting sedation was superior
The combination of sedation interruption and a spontaneous breathing trial was superior to a spontaneous breathing trial alone. The mean number of ventilator-free days:
- 14.7 ± 0.9 with sedation interruption
- 11.6 ± 0.9 days with usual care (P = .02).
The median time to ICU discharge:
- 9.1 days with sedation interruption (interquartile range 5.1 to 17.8)
- 12.9 days with usual care (interquartile range 6.0 to 24.2, P = .01).
The mortality rate at 28 days:
- 28% with sedation interruption
- 35% with usual care (P = .21).
The mortality rate at 1 year:
- 44% with sedation interruption
- 58% with usual care (hazard ratio [HR] in the intervention group 0.68, 95% CI 0.50–0.92, P = .01).
Of note, patients in the intervention group had a higher rate of self-extubation (9.6% vs 3.6%, P = .03), but the rate of reintubation was similar between the groups (14% vs 13%, P = .47).
Comments
The addition of daily awakenings to spontaneous breathing trials results in a further reduction in the number of ICU days and increases the number of ventilator-free days.
Of note, the protocol allowed patients in the control group to undergo a spontaneous breathing trial while on sedatives (69% of the patients were receiving sedation at the time). Therefore, a bias effect in favor of the intervention group cannot be excluded. However, both groups had to meet criteria for readiness for spontaneous breathing.
The study demonstrates the safety of daily awakenings and confirms previous findings suggesting that a daily trial of spontaneous breathing results in better ICU outcomes.
GLUCOSE CONTROL IN THE ICU
Key points
- Although earlier studies suggested that intensive insulin therapy might be beneficial in critically ill patients, new findings show that strict glucose control can lead to complications without improving outcomes.
Background
A previous study15 found that intensive insulin therapy to maintain a blood glucose level between 80 and 110 mg/dL (compared with 180–200 mg/dL) reduced the mortality rate in surgical critical care patients. The mortality rate in the ICU was 4.6% with intensive insulin therapy vs 8.0% with conventional therapy (P < .04), and the effect was more robust for patients who remained longer than 5 days in the ICU (10.6% vs 20.2%).
Importantly, however, hypoglycemia (defined as blood glucose ≤ 40 mg/dL) occurred in 39 patients in the intensive-treatment group vs 6 patients in the conventional-treatment group.
The NICE-SUGAR trial
NICE-SUGAR STUDY INVESTIGATORS; FINFER S, CHITTOCK DR, SU SY, ET AL. INTENSIVE VERSUS CONVENTIONAL GLUCOSE CONTROL IN CRITICALLY ILL PATIENTS. N ENGL J MED 2009; 360:1283–1297.
The Normoglycemia in Intensive Care Evaluation-Survival Using Glucose Algorithm Regulation (NICE-SUGAR) trial16 randomized 6,104 patients in medical and surgical ICUs to receive either intensive glucose control (blood glucose 81–108 mg/dL) with insulin therapy or conventional glucose control (blood glucose < 180 mg/dL). In the conventional-control group, insulin was discontinued if the blood glucose level dropped below 144 mg/dL.
A higher mortality rate with intensive glucose control
As expected, the intensive-control group achieved lower blood glucose levels: 115 vs 144 mg/dL.
Nevertheless, intensive glucose control was associated with a higher incidence of severe hypoglycemia, defined as a blood glucose level lower than 40 mg/dL: 6.8% vs 0.5%.
More importantly, compared with conventional insulin therapy, intensive glucose control was associated with a higher 90-day mortality rate: 27.5% vs 24.9% (odds ratio 1.14, 95% CI 1.02–1.28). These findings were similar in the subgroup of surgical patients (24.4% vs 19.8%, odds ratio 1.31, 95% CI 1.07–1.61).
Comments
Of note, the conventional-control group had more patients who discontinued the treatment protocol prematurely. Additionally, more patients in this group received corticosteroids.
These results widely differ from those of a previous study by van den Berghe et al,15 which showed that tight glycemic control is associated with a survival benefit. The differences in outcomes are probably largely related to different patient populations, as van den Berghe et al included patients who had undergone cardiac surgery, who were more likely to benefit from strict blood glucose control.
The VISEP trial
BRUNKHORST FM, ENGEL C, BLOOS F, ET AL; GERMAN COMPETENCE NETWORK SEPSIS (SEPNET). INTENSIVE INSULIN THERAPY AND PENTASTARCH RESUSCITATION IN SEVERE SEPSIS. N ENGL J MED 2008; 358:125–139.
The Volume Substitution and Insulin Therapy in Severe Sepsis (VISEP) trial was a multicenter study designed to compare intensive insulin therapy (target blood glucose level 80–110 mg/dL) and conventional glucose control (target blood glucose level 180–200 mg/dL) in patients with severe sepsis.17 It also compared two fluids for volume resuscitation: 10% pentastarch vs modified Ringer's lactate. It included both medical and surgical patients.
Trial halted early for safety reasons
The mean morning blood glucose level was significantly lower in the intensive insulin group (112 vs 151 mg/dL).
Severe hypoglycemia (blood glucose ≤ 40 mg/dL) was more common in the group that received intensive insulin therapy (17% vs 4.1%, P < .001).
Mortality rates at 28 days did not differ significantly: 24.7% with intensive control vs 26.0% with conventional glucose control. The mortality rate at 90 days was 39.7% in the intensive therapy group and 35.4% in the conventional therapy group, but the difference was not statistically significant.
The intensive insulin arm of the trial was stopped after 488 patients were enrolled because of a higher rate of hypoglycemia (12.1% vs 2.1%) and of serious adverse events (10.9% vs 5.2%).
Additionally, the fluid resuscitation arm of the study was suspended at the first planned interim analysis because of a higher risk of organ failure in the 10% pentastarch group.
CORTICOSTEROID THERAPY IN SEPTIC SHOCK
Key points
- Corticosteroid therapy improves hemodynamic outcomes in patients with severe septic shock.
- Although meta-analyses suggest the mortality rate is lower with corticosteroid therapy, there is not enough evidence from randomized controlled trials to prove that the use of low-dose corticosteroids lowers the mortality rate in patients with septic shock.
- The corticotropin (ACTH) stimulation test should not be used to determine the need for corticosteroids in patients with septic shock.
Background
A previous multicenter study,18 performed in France, found that the use of corticosteroids in patients with septic shock resulted in lower rates of death at 28 days, in the ICU, and in the hospital and a shorter time to vasopressor withdrawal. Nevertheless, the beneficial effects were not observed in patients with adequate adrenal reserve (based on an ACTH stimulation test).
This study was criticized because of a high mortality rate in the placebo group.
The CORTICUS study
SPRUNG CL, ANNANE D, KEH D, ET AL; CORTICUS STUDY GROUP. HYDROCORTISONE THERAPY FOR PATIENTS WITH SEPTIC SHOCK. N ENGL J MED 2008; 358:111–124.
The Corticosteroid Therapy of Septic Shock (CORTICUS) study was a multicenter trial that randomly assigned 499 patients with septic shock to receive hydrocortisone (50 mg intravenously every 6 hours for 5 days, followed by a 6-day taper period) or placebo.19
Patients were eligible to be enrolled within 72 hours of onset of shock. Similar to previous studies, the CORTICUS trial classified patients on the basis of an ACTH stimulation test as having inadequate adrenal reserve (a cortisol increase of ≤ 9 μg/dL) or adequate adrenal reserve (a cortisol increase of > 9 μg/dL).
Faster reversal of shock with steroids
At baseline, the mean Simplified Acute Physiologic Score II (SAPS II) was 49 (the range of possible scores is 0 to 163; the higher the score the worse the organ dysfunction).
Hydrocortisone use resulted in a shorter duration of vasopressor use and a faster reversal of shock (3.3 days vs 5.8 days, P < .001).
This association was the same when patients were divided according to response to ACTH stimulation test. Time to reversal of shock in responders:
- 2.8 days with hydrocortisone
- 5.8 days with placebo (P < .001).
Time to reversal of shock in nonresponders:
- 3.9 days with hydrocortisone
- 6.0 days with placebo (P = .06).
Nevertheless, the treatment did not reduce the mortality rate at 28 days overall (34.3% vs 31.5% P = .51), or in the subgroups based on response to ACTH, or at any other time point. A post hoc analysis suggested that patients who had a systolic blood pressure of less than 90 mm Hg within 30 minutes of enrollment had a greater benefit in terms of mortality rate, but the effect was not statistically significant: the absolute difference was −11.2% (P = 0.28). Similarly, post hoc analyses also revealed a higher rate of death at 28 days in patients who received etomidate (Amidate) before randomization in both groups (P = .03).
Importantly, patients who received corticosteroids had a higher incidence of superinfections, including new episodes of sepsis or septic shock, with a combined odds ratio of 1.37 (95% CI 1.05–1.79).
Length of stay in the hospital or in the ICU was similar in patients who received corticosteroids and in those who received placebo. The ICU length of stay was 19 ± 31 days with hydrocortisone vs 18 ± 17 days with placebo (P = .51).
Comments
The CORTICUS trial showed that low-dose corticosteroid therapy results in faster reversal of shock in patients with severe septic shock. The hemodynamic benefits are present in all patients regardless of response to the ACTH stimulation test.
Nevertheless, contrary to previous findings,18 corticosteroid use was not associated with an improvement in mortality rates. Important differences exist between these two studies:
- The mortality rates in the placebo groups were significantly different (> 50% in the French study vs 30% in CORTICUS).
- The SAPS II scores were different in these two trials (55 vs 49), suggesting a greater severity of illness in the French study.
- The criteria for enrollment were different: the French study included patients who had a systolic blood pressure lower than 90 mm Hg for more than 1 hour despite fluid administration and vasopressor use, whereas the CORTICUS trial included patients who had a systolic blood pressure lower than 90 mm Hg for more than 1 hour despite fluid administration or vasopressor use.
- The time of enrollment was different: patients were enrolled much faster in the French study (within 8 hours) than in the CORTICUS trial (within 72 hours).
A recent meta-analysis of 17 randomized trials (including the CORTICUS study), found that, compared with those who received placebo, patients who received corticosteroids had a small reduction in the 28-day mortality rate (HR 0.84, 95% CI 0.71–1.00, P < .05).20 Of note, this meta-analysis has been criticized for possible publication bias and also for a large degree of heterogeneity in its results.21
VASOPRESSOR THERAPY IN SHOCK
Key points
- Vasopressin use in patients with severe septic shock is not associated with an improvement in mortality rates.
- Vasopressin should not be used as a first-line agent in patients with septic shock.
- Norepinephrine should be considered a first-line agent in patients with shock.
- Compared with norepinephrine, the use of dopamine in patients with shock is associated with similar mortality rates, although its use may result in a greater number of cardiac adverse events.
Background
Vasopressin gained popularity in critical care in the last 10 years because several small studies showed that adding it improves hemodynamics and results in a reduction in the doses of catecholamines in patients with refractory septic shock.22 Furthermore, the Surviving Sepsis Campaign guidelines recommended the use of vasopressin in patients who have refractory shock despite fluid resuscitation and the use of other “conventional” vasopressors.23
Despite these positive findings, it remained unknown if the use of vasopressin increases the survival rate in patients with septic shock.
The Vasopressin and Septic Shock Trial (VASST)
RUSSELL JA, WALLEY KR, SINGER J, ET AL; VASST INVESTIGATORS. VASOPRESSIN VERSUS NOREPINEPHRINE INFUSION IN PATIENTS WITH SEPTIC SHOCK. N ENGL J MED 2008; 358:877–887.
The Vasopressin and Septic Shock Trial (VASST)24 was a multicenter randomized, double-blind, controlled trial that included 778 patients with refractory septic shock. Refractory shock was defined as the lack of a response to a normal saline fluid bolus of 500 mL or the need for vasopressors (norepinephrine in doses of at least 5 μg/minute or its equivalent for 6 hours or more in the 24 hours before randomization).
Two subgroups were identified: those with severe septic shock (requiring norepinephrine in doses of 15 μg/minute or higher) and those with less-severe septic shock (needing norepinephrine in doses of 5 to 14 μg/minute). Patients with unstable coronary artery disease (acute myocardial infarction, angina) and severe congestive heart failure were excluded.
Patients were randomized to receive an intravenous infusion of vasopressin (0.01–0.03 U/minute) or norepinephrine (5–15 mg/minute) in addition to open-labeled vasopressors (excluding vasopressin). The primary outcome was the all-cause mortality rate at 28 days.
Results
At 28 days, fewer patients had died in the vasopressin group than in the norepinephrine group (35.4% vs 39.3%), but the difference was not statistically significant (P = .26). The trend was the same at 90 days (mortality rate 43.9% vs 49.6%, P = .11).
Subgroup analysis showed that in patients with less-severe septic shock, those who received vasopressin had a lower mortality rate at 28 days (26.5% vs 35.7%, P = .05; relative risk 0.74; 95% CI 0.55–1.01) and at 90 days (35.8% vs 46.1%, P = .04; relative risk 0.78, 95% CI 0.61–0.99).
There were no statistically significant differences in any of the other secondary outcomes or in serious adverse events.
Comments
The study has been criticized for several reasons:
- The mean arterial blood pressure at baseline before initiation of vasopressin was 72 mm Hg (and some argue that vasopressin was therefore not needed by the time it was started).
- The time from screening to infusion of the study drug was very long (12 hours).
- The observed mortality rate was lower than expected (37%).
Despite these considerations, the VASST trial showed that vasopressin is not associated with an increased number of adverse events in patients without active cardiovascular disease. The possible benefit in terms of the mortality rate in the subgroup of patients with less-severe septic shock requires further investigation.
Is dopamine equivalent to norepinephrine?
Previously, the Sepsis Occurrence in Acutely Ill Patients (SOAP) study, a multicenter, observational cohort study, found that dopamine use was associated with a higher all-cause mortality rate in the ICU compared with no dopamine.25 This finding had not been reproduced, as few well-designed studies had compared the effects of dopamine and norepinephrine.
The SOAP II study
DE BACKER D, BISTON P, DEVRIENDT J, ET AL; SOAP II INVESTIGATORS.. COMPARISON OF DOPAMINE AND NOREPINEPHRINE IN THE TREATMENT OF SHOCK. N ENGL J MED 2010; 362:779–789.
The SOAP II study,26 a multicenter, randomized trial, compared dopamine vs norepinephrine as first-line vasopressor therapy. In patients with refractory shock despite use of dopamine 20 μg/kg/minute or norepinephrine 0.19 μg/kg/minute, open-label norepinephrine, epinephrine, or vasopressin was added.
The primary outcome was the mortality rate at 28 days after randomization; secondary end points included the number of days without need for organ support and the occurrence of adverse events.
Results
A total of 1,679 patients were included; 858 were assigned to dopamine and 821 to norepinephrine. Most (1,044, 62%) of the patients had a diagnosis of septic shock.
No significant difference in mortality rates was noted at 28 days: 52.5% with dopamine vs 48.5% with norepinephrine (P = .10).
However, there were more arrhythmias in the patients treated with dopamine: 207 events (24.1%) vs 102 events (12.4%) (P < .001). The number of other adverse events such as renal failure, myocardial infarction, arterial occlusion, or skin necrosis was not different between the groups.
A subgroup analysis showed that dopamine was associated with more deaths at 28 days in patients with cardiogenic shock (P = .03) but not in patients with septic shock (P = .19) or with hypovolemic shock (P = .84).
Comments
The study was criticized because the patients may not have received adequate fluid resuscitation (the study considered adequate resuscitation to be equivalent to 1 L of crystalloids or 500 mL of colloids), as different degrees of volume depletion among patients make direct comparisons of vasopressor effects difficult.
Additionally, the study defined dopamine 20 μg/kg/minute as being equipotent with norepinephrine 0.19 μg/kg/minute. Comparisons of potency between drugs are difficult to establish, as there are no available data.
Nevertheless, this study further confirms previous findings suggesting that norepinephrine is not associated with more end-organ damage (such as renal failure or skin ischemia), and shows that dopamine may increase the number of adverse events, particularly in patients with cardiac disease.
- Shah MR, Hasselblad V, Stevenson LW, et al. Impact of the pulmonary artery catheter in critically ill patients: meta-analysis of randomized clinical trials. JAMA 2005; 294:1664–1670.
- National Heart, Lung, and Blood Institute Acute Respiratory Distress Syndrome (ARDS) Clinical Trials Network; Wiedemann HP, Wheeler AP, Bernard GR, et al. Comparison of two fluid-management strategies in acute lung injury. N Engl J Med 2006; 354:2564–2575.
- National Heart, Lung, and Blood Institute Acute Respiratory Distress Syndrome (ARDS) Clinical Trials Network; Wheeler AP, Bernard GR, Thompson BT, et al. Pulmonary-artery versus central venous catheter to guide treatment of acute lung injury. N Engl J Med 2006; 354:2213–2224.
- Bernard GR, Luce JM, Sprung CL, et al. High-dose corticosteroids in patients with the adult respiratory distress syndrome. N Engl J Med 1987; 317:1565–1570.
- Meduri GU, Headley AS, Golden E, et al. Effect of prolonged methylprednisolone therapy in unresolving acute respiratory distress syndrome: a randomized controlled trial. JAMA 1998; 280:159–165.
- Steinberg KP, Hudson LD, Goodman RB, et al; National Heart, Lung, and Blood Institute Acute Respiratory Distress Syndrome (ARDS) Clinical Trials Network. Efficacy and safety of corticosteroids for persistent acute respiratory distress syndrome. N Engl J Med 2006; 354:1671–1684.
- Meduri GU, Golden E, Freire AX, et al. Methylprednisolone infusion in early severe ARDS: results of a randomized controlled trial. Chest 2007; 131:954–963.
- Meduri GU, Golden E, Freire AX, et al. Methylprednisolone infusion in early severe ARDS results of a randomized controlled trial. 2007. Chest 2009; 136(suppl 5):e30.
- Annane D, Sébille V, Bellissant E; Ger-Inf-05 Study Group. Effect of low doses of corticosteroids in septic shock patients with or without early acute respiratory distress syndrome. Crit Care Med 2006; 34:22–30.
- Kollef MH, Levy NT, Ahrens TS, Schaiff R, Prentice D, Sherman G. The use of continuous i.v. sedation is associated with prolongation of mechanical ventilation. Chest 1998; 114:541–548.
- Carson SS, Kress JP, Rodgers JE, et al. A randomized trial of intermittent lorazepam versus propofol with daily interruption in mechanically ventilated patients. Crit Care Med 2006; 34:1326–1332.
- Brook AD, Ahrens TS, Schaiff R, et al. Effect of a nursing-implemented sedation protocol on the duration of mechanical ventilation. Crit Care Med 1999; 27:2609–2615.
- Kress JP, Pohlman AS, O’Connor MF, Hall JB. Daily interruption of sedative infusions in critically ill patients undergoing mechanical ventilation. N Engl J Med 2000; 342:1471–1477.
- Girard TD, Kress JP, Fuchs BD, et al. Efficacy and safety of a paired sedation and ventilator weaning protocol for mechanically ventilated patients in intensive care (Awakening and Breathing Controlled trial): a randomised controlled trial. Lancet 2008; 371:126–134.
- van den Berghe G, Wouters P, Weekers F, et al. Intensive insulin therapy in the critically ill patients. N Engl J Med 2001; 345:1359–1367.
- NICE-SUGAR Study Investigators; Finfer S, Chittock DR, Su SY, et al. Intensive versus conventional glucose control in critically ill patients. N Engl J Med 2009; 360:1283–1297.
- Brunkhorst FM, Engel C, Bloos F, et al; German Competence Network Sepsis (SepNet). Intensive insulin therapy and pentastarch resuscitation in severe sepsis. N Engl J Med 2008; 358:125–139.
- Annane D, Sébille V, Charpentier C, et al. Effect of treatment with low doses of hydrocortisone and fludrocortisone on mortality in patients with septic shock. JAMA 2002; 288:862–871.
- Sprung CL, Annane D, Keh D, et al; CORTICUS Study Group. Hydrocortisone therapy for patients with septic shock. N Engl J Med 2008; 358:111–124.
- Annane D, Bellissant E, Bollaert PE, et al. Corticosteroids in the treatment of severe sepsis and septic shock in adults: a systematic review. JAMA 2009; 301:2362–2375.
- Minneci PC, Deans KJ, Natanson C. Corticosteroid therapy for severe sepsis and septic shock [letter]. JAMA 2009; 302:16443–1644.
- Kampmeier TG, Rehberg S, Westphal M, Lange M. Vasopressin in sepsis and septic shock. Minerva Anestesiol 2010; 76:844–850.
- Dellinger RP, Levy MM, Carlet JM, et al; International Surviving Sepsis Campaign Guidelines Committee. Surviving Sepsis Campaign: international guidelines for management of severe sepsis and septic shock: 2008. Crit Care Med 2008; 36:296–327.
- Russell JA, Walley KR, Singer J, et al; VASST Investigators. Vasopressin versus norepinephrine infusion in patients with septic shock. N Engl J Med 2008; 358:877–887.
- Sakr Y, Reinhart K, Vincent JL, et al. Does dopamine administration in shock influence outcome? Results of the Sepsis Occurrence in Acutely Ill Patients (SOAP) Study. Crit Care Med 2006; 34:589–597.
- De Backer D, Biston P, Devriendt J, et al; SOAP II Investigators. Comparison of dopamine and norepinephrine in the treatment of shock. N Engl J Med 2010; 362:779–789.
- Shah MR, Hasselblad V, Stevenson LW, et al. Impact of the pulmonary artery catheter in critically ill patients: meta-analysis of randomized clinical trials. JAMA 2005; 294:1664–1670.
- National Heart, Lung, and Blood Institute Acute Respiratory Distress Syndrome (ARDS) Clinical Trials Network; Wiedemann HP, Wheeler AP, Bernard GR, et al. Comparison of two fluid-management strategies in acute lung injury. N Engl J Med 2006; 354:2564–2575.
- National Heart, Lung, and Blood Institute Acute Respiratory Distress Syndrome (ARDS) Clinical Trials Network; Wheeler AP, Bernard GR, Thompson BT, et al. Pulmonary-artery versus central venous catheter to guide treatment of acute lung injury. N Engl J Med 2006; 354:2213–2224.
- Bernard GR, Luce JM, Sprung CL, et al. High-dose corticosteroids in patients with the adult respiratory distress syndrome. N Engl J Med 1987; 317:1565–1570.
- Meduri GU, Headley AS, Golden E, et al. Effect of prolonged methylprednisolone therapy in unresolving acute respiratory distress syndrome: a randomized controlled trial. JAMA 1998; 280:159–165.
- Steinberg KP, Hudson LD, Goodman RB, et al; National Heart, Lung, and Blood Institute Acute Respiratory Distress Syndrome (ARDS) Clinical Trials Network. Efficacy and safety of corticosteroids for persistent acute respiratory distress syndrome. N Engl J Med 2006; 354:1671–1684.
- Meduri GU, Golden E, Freire AX, et al. Methylprednisolone infusion in early severe ARDS: results of a randomized controlled trial. Chest 2007; 131:954–963.
- Meduri GU, Golden E, Freire AX, et al. Methylprednisolone infusion in early severe ARDS results of a randomized controlled trial. 2007. Chest 2009; 136(suppl 5):e30.
- Annane D, Sébille V, Bellissant E; Ger-Inf-05 Study Group. Effect of low doses of corticosteroids in septic shock patients with or without early acute respiratory distress syndrome. Crit Care Med 2006; 34:22–30.
- Kollef MH, Levy NT, Ahrens TS, Schaiff R, Prentice D, Sherman G. The use of continuous i.v. sedation is associated with prolongation of mechanical ventilation. Chest 1998; 114:541–548.
- Carson SS, Kress JP, Rodgers JE, et al. A randomized trial of intermittent lorazepam versus propofol with daily interruption in mechanically ventilated patients. Crit Care Med 2006; 34:1326–1332.
- Brook AD, Ahrens TS, Schaiff R, et al. Effect of a nursing-implemented sedation protocol on the duration of mechanical ventilation. Crit Care Med 1999; 27:2609–2615.
- Kress JP, Pohlman AS, O’Connor MF, Hall JB. Daily interruption of sedative infusions in critically ill patients undergoing mechanical ventilation. N Engl J Med 2000; 342:1471–1477.
- Girard TD, Kress JP, Fuchs BD, et al. Efficacy and safety of a paired sedation and ventilator weaning protocol for mechanically ventilated patients in intensive care (Awakening and Breathing Controlled trial): a randomised controlled trial. Lancet 2008; 371:126–134.
- van den Berghe G, Wouters P, Weekers F, et al. Intensive insulin therapy in the critically ill patients. N Engl J Med 2001; 345:1359–1367.
- NICE-SUGAR Study Investigators; Finfer S, Chittock DR, Su SY, et al. Intensive versus conventional glucose control in critically ill patients. N Engl J Med 2009; 360:1283–1297.
- Brunkhorst FM, Engel C, Bloos F, et al; German Competence Network Sepsis (SepNet). Intensive insulin therapy and pentastarch resuscitation in severe sepsis. N Engl J Med 2008; 358:125–139.
- Annane D, Sébille V, Charpentier C, et al. Effect of treatment with low doses of hydrocortisone and fludrocortisone on mortality in patients with septic shock. JAMA 2002; 288:862–871.
- Sprung CL, Annane D, Keh D, et al; CORTICUS Study Group. Hydrocortisone therapy for patients with septic shock. N Engl J Med 2008; 358:111–124.
- Annane D, Bellissant E, Bollaert PE, et al. Corticosteroids in the treatment of severe sepsis and septic shock in adults: a systematic review. JAMA 2009; 301:2362–2375.
- Minneci PC, Deans KJ, Natanson C. Corticosteroid therapy for severe sepsis and septic shock [letter]. JAMA 2009; 302:16443–1644.
- Kampmeier TG, Rehberg S, Westphal M, Lange M. Vasopressin in sepsis and septic shock. Minerva Anestesiol 2010; 76:844–850.
- Dellinger RP, Levy MM, Carlet JM, et al; International Surviving Sepsis Campaign Guidelines Committee. Surviving Sepsis Campaign: international guidelines for management of severe sepsis and septic shock: 2008. Crit Care Med 2008; 36:296–327.
- Russell JA, Walley KR, Singer J, et al; VASST Investigators. Vasopressin versus norepinephrine infusion in patients with septic shock. N Engl J Med 2008; 358:877–887.
- Sakr Y, Reinhart K, Vincent JL, et al. Does dopamine administration in shock influence outcome? Results of the Sepsis Occurrence in Acutely Ill Patients (SOAP) Study. Crit Care Med 2006; 34:589–597.
- De Backer D, Biston P, Devriendt J, et al; SOAP II Investigators. Comparison of dopamine and norepinephrine in the treatment of shock. N Engl J Med 2010; 362:779–789.
KEY POINTS
- In patients with acute respiratory distress syndrome (ARDS), fluid restriction is associated with better outcomes. A pulmonary arterial catheter is not indicated in the routine management of ARDS. Corticosteroid use can result in improved oxygenation but may be associated with worse outcomes if treatment is started late, ie, more than 14 days after the onset of the disease.
- Intensive insulin therapy is associated with hypoglycemia and may be associated with complications in medical patients.
- In patients with septic shock, corticosteroid therapy is associated with faster shock reversal, but its effects on mortality rates remain controversial. Vasopressin improves hemodynamic variables but is not associated with a lower mortality rate.
- Daily interruption of sedation and early awakening of mechanically ventilated patients result in better outcomes.
- Compared with norepinephrine, dopamine is associated with more cardiac adverse events in patients with shock.