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Patient Safety and Quality

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Extended resident work hours jeopardize both resident health and patient safety

In 2003, the Accreditation Council for Graduate Medical Education mandated a maximum 80-hour work week for medical residents, restricted continuous on-call shifts to 30 hours, and insisted that residents have 1 day off per week. However, flexibility in meeting these standards has largely permitted a continuation of the status quo in most hospitals. Very little data support the scheduling of medical trainees to work shifts longer than 24 hours, according to researchers at the Harvard Work Hours Health and Safety Group. In a recent paper, they reviewed the physiological principles underlying fatigue, as well as the results of a series of studies by the Group which quantified the negative effects of extended work shifts on resident health and patient safety.

For example, a nationwide survey by the Group found that residents who had worked 24 hours or longer were 2.3 times more likely to have a motor vehicle crash following that shift than when they worked less than 24 hours. Also, the monthly risk of a crash increased by 16 percent after each extended duration shift. A randomized trial by the Group showed that interns working a traditional on-call schedule (which routinely included shifts of more than 30 hours) slept nearly 6 fewer hours per week, had twice as many attentional failures on duty overnight, made 36 percent more serious medical errors, and made nearly 6 times more serious diagnostic errors than when working on a schedule that limited continuous duty to 16 hours.

In contrast, an intervention study by the Group found that restricting residents to 16 hours of scheduled continuous duty increased sleep duration outside work, improved attentiveness on duty overnight, and reduced the rate of medical errors. These improvements occurred despite the addition of a fourth resident to the team and an increase in the number of hand offs between physicians. This suggests that the perceived risk of changing continuity of care due to shortened shifts is less than the risk of error due to sleep deprivation. Eliminating these extended duration shifts outright is likely to have a much greater impact of resident health and patient safety than attempting to achieve an arbitrary work-hour limit of 80 hours per week, conclude the researchers. Their work is supported in part by the Agency for Healthcare Research and Quality (HS12032, HS15906, and HS13333).

See "When policy meets physiology," by Steven W. Lockley, Ph.D., Christopher P. Landrigan, M.D., M.P.H., Laura K. Barger, Ph.D., and Charles A. Czeisler, Ph.D., M.D., in the August 2006 Clinical Orthopaedics and Related Research 449, pp. 116-127.

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