Extended Work Hours Associated with Increased Risk of Medical Errors, Death
Researchers from the Division of Sleep Medicine at Brigham and Women's Hospital (BWH) found that doctors-in-training, or interns, were four times more likely to make fatigue-related medical errors that contributed to the death of a patient after working five extra long shifts per month, 24 or more hours without rest, compared to months when they did not work extended-duration shifts. The study appears in the December 12, 2006 issue of the journal Public Library of Science (PloS) Medicine and focuses on the issue of interns working within work-hour limits set by the Accreditation Council for Graduate Medical Education (ACGME).
"These data demonstrate that the standard practice of scheduling young doctors to work marathon shifts lasting 30 consecutive hours twice a week during their training presents a grave risk to the patients with whose care they are entrusted," said senior author Charles A. Czeisler, MD, PhD, chief of the Division of Sleep Medicine at BWH and Baldino Professor of Sleep Medicine at Harvard Medical School (HMS).
Czeisler and colleagues conducted a web-based survey across the US in which 2,737 interns from across specialties completed 17,003 confidential monthly reports. Each intern acted as his or her own control.
The researchers observed that compared to months in which no extended-duration shifts were worked, interns were:
- 3.5 times more likely to report at least one fatigue-related significant medical error during months they worked one to four extended duration shifts
- 7.5 times more likely to report at least one fatigue-related significant medical error during months they worked five or more extended-duration shifts
- 8.7 times more likely to report at least one fatigue-related preventable adverse event that harmed the patient during months they worked one to four extended-duration shifts
- 7 times more likely to report at least one fatigue-related preventable adverse event that harmed the patient during months they worked five or more extended-duration shifts
- 4.1 times more likely to report at least one fatigue-related preventable adverse event that resulted in the death of the patient during months they worked five or more extended-duration shifts
- More likely to report more attentional failures - or "nodding off or falling asleep" - during lectures, rounds and clinical activities including surgery during months they worked five or more extended duration shifts.
In 2003, the ACGME implemented work-hour limits for all physicians-in-training in the United States. Under these guidelines, interns are limited to work a maximum of 30 hours in a row and no more than 80 weekly hours, averaged over four weeks. Additionally, interns are supposed to be off from work one in seven days.
A separate BWH study this fall found that interns from across the country commonly reported non-compliance with work-hour limits in the first year following implementation of restrictions set by the ACGME. In addition, interns' average work duration showed only a minor decrease and their average sleep time only slightly increased.
"It is clear that sleep deprivation takes its toll over time on physicians," said author Laura Barger, PhD, a research associate in Medicine at BWH and HMS. "While tradition holds that forcing young doctors to work extended-duration shifts teaches them to become better doctors, the evidence shows that this method of education is dangerous to patients."
Health and Human Services' Agency for Healthcare Research and Quality and the National Institute for Occupational Safety and Health within the Centers for Disease Control and Prevention funded this research.