Residency programs open eyes to sleep deprivation

Duty hours rules may face more changes

Grueling schedules and sleep deprivation long have been hallmarks of medical residency. But with a growing number of studies linking sleep deprivation to medical errors and worker injuries, pressure is building to rethink the method of medical education.

The Joint Commission is considering adding a National Patient Safety Goal on health care worker fatigue, which would include medical residents. Based on research it sponsored, the federal Agency for Healthcare Research and Quality addresses resident work hours in two of 10 patient safety tips: It advises hospitals to "limit shifts of more than 24 hours for medical residents" and "eliminate the tradition of shifts of more than 30 consecutive hours by interns working in hospital ICUs."

"It's a grave issue," says Charles Czeisler, PhD, MD, director of the Division of Sleep Medicine at Harvard Medical School and chief of the Division of Sleep Medicine at Brigham and Women's Hospital in Boston.

"One out of five interns reports to us that [while] working these schedules, they have made a fatigue-related mistake that has seriously injured a patient in the previous year. One out of 20 has reported to us that they made a fatigue-related mistake that resulted in the death of a patient.

"That means that tens of thousands of patients have been seriously injured and thousands have been killed" due to sleep deprivation of medical residents, Czeisler says.

Currently, the American Council for Graduate Medical Education (ACGME) in Chicago limits resident work hours to 24 hours plus six additional hours for paperwork and other nonclinical tasks. Residents may not work more than 80 hours a week, averaged over a four-week period, according to ACGME standards. New York is the only state to restrict resident work hours by law, with rules that limit resident shifts to 24 hours plus three additional nonclinical hours.

Specialty groups, such as the American College of Surgeons, have expressed concern that work hour restrictions would cut the training of young surgeons. Questions also have been raised about continuity of care and the impact of residents who "time out" and must leave care in the hands of a resident unfamiliar with their patients.

ACGME is continuing to look at changes in resident scheduling and work hours, says Ingrid Philibert, MHA, MBA, ACGME senior vice president for field activities. Limits on work hours must be balanced with other considerations, she says.

"Residents have to have continuous exposure to a given patient to see how the patient progresses," she says. "It's very hard to learn that through short snippets of exposure to different patients."

Others favor some absolute limits. Even a 24-hour shift is dangerously long, contends Peter Lurie, MD, deputy director of the Health Research Group of Public Citizen in Washington, DC. Studies show that staying awake for 24 or more hours results in performance deficits similar to having a 0.1 blood alcohol level — beyond the limit for driving under the influence.1 "It's antithetical to quality of patient care," he says.

Fixing the problem of resident work hours requires a restructuring of schedules — and money to add more resources. It can be costly to hire additional nurse practitioners and physician assistants or other support staff to take over some duties from residents. Teaching hospitals typically have patients with high acuity — often patients who do not have health insurance — and they run on thin margins, says Philibert.

Yet Czeisler notes that teaching hospitals receive funds specifically to cover to supervision and educational support of residents. Patients and their insurance companies are billed for the clinical care. "They're provided enough money through the Medicare program to hire fully trained physicians to supervise those trainees and for them to work reasonable hours," he says. "With the money they get from the clinical care of those patients, they can provide for their clinical care, just as do hospitals that don't have interns and residents."

Shorter hours lead to fewer errors

It seems like common sense that chronic sleep deprivation can affect performance. That is the basis for work shift limits in the trucking and airline industries. But recent studies have highlighted specific risks in health care.

Residents who worked extended shifts of 24 hours or more were more than twice as likely to have car accidents on the way home from work and almost six times as likely to have a near-miss, according to the Harvard Work Hours, Health, and Safety study.2

Percutaneous injuries were 73% more frequent among resident working extended work hours (at least 24 hours) than those with nonextended shifts. Residents cited lapses in concentration and fatigue as the primary contributing factors.3

Even more troubling, a survey of medical residents found that they reported significantly more serious medical errors after working extended shifts. Those who reported working more than five extended (24-hour) shifts in a month also were seven times more likely to report a fatigue-related serious medical error.4

Conversely, reducing interns' work hours led to a 36% reduction in medical errors, Czeisler and his colleagues found. Schedules were redesigned at Brigham and Women's Hospital in Boston, splitting the interns' on-call shifts to "day call" and "night call." The schedule was designed for 16-hour shifts and, although the interns sometimes exceeded that, they eliminated shifts of 24 hours or more and reduced overall hours from about 80 per week to about 63 per week.5

To improve continuity, the interns' schedules overlapped by an hour and the interns completed a sign-out form on each patient. To collect information on errors, two nurses reviewed medical charts and six physicians observed interns.

Schedules must be carefully designed to reduce errors, notes Czeisler. For example, Brigham and Women's decided not to use "night float" residents who would not be familiar with the patients.

Czeisler also notes that there are psychological repercussions for interns and residents who make serious medical errors due to fatigue. "These are very caring individuals who have gone in with a lot of enthusiasm and dedication," he says. "They're working themselves to the bone to try to do the best job they can, but they're subjected to schedules that the brain can't properly perform."

ACGME: Most programs comply

The ACGME contends that its standards have worked to reduce resident work hours, and that few programs are substantially out of compliance. In 2004-2005, the ACGME cited 7% of programs for violating duty hours standards. Those are hospitals in which more than 15% of residents report violations of duty hours.

Some violations of the duty hours requirement occur because individual residents overstay their shift to finish up work or to observe an interesting case, says Philibert.

"In each program there probably are a few residents who run over the duty hours on a regular basis," she says. "This should be of interest to directors who may want to help them with time management. We would be unnecessarily obtrusive if we cited programs if they had one or two residents over."

Do residents lie to cover up their extended work hours so their programs won't be cited? "We are aware that residents in some surgical specialties lie on their duty hour reports to ACGME," says Philibert. "It's a professionalism issue." ACGME addresses those situations with program directors, she says. "We want the data to be accurate. We don't want it to be whitewashed and for us just to look compliant."

Czeisler contends that, based on his research, compliance is far less than what is reported to ACGME. "It's not an isolated incident. It's 60% of the months, 85% of the interns reporting violations," he says.

There is one area of concord on the issue of work hours: The ACGME is reviewing different scheduling structures, including the shorter shifts implemented at Brigham and Women's Hospital as a part of the ICU study.

"We are still exploring the effect of our putting in these [duty hours] standards," says Philibert. "We are still open to future refinements. We think of the duty hour limits as one of a whole host of standards that make for good patient care."


1. Lamond N, Dawson D. Quantifying the performance impairment associated with fatigue. J Sleep Res 1999; 8:255-62.

2. Barger LK, Cade BE, Ayas N, et al. Extended work shifts and the risk of motor vehicle crashes among interns. N Engl J Med 2005; 352:125-134.

3. Ayas NT, Barger LK, Cade BE, et al. Extended work duration and the risk of self-reported percutaneous injuries in interns. JAMA 2006; 296:1,055-1,062.

4. Barger LK, Ayas NT, Cade BE, et al. (2006) Impact of Extended-Duration Shifts on Medical Errors, Adverse Events, and Attentional Failures. PLoS Med 2006; 3(12): Available at

5. Landrigan CP, Rothschild JM, Cronin JM, et al. Effect of reducing interns' work hours on serious medical errors in intensive care units. N Engl J Med 2004; 351(18):1838-1848.