News | July 15, 2007

Study Shows the Impact of Limiting Hours for Physician Trainees

July 16, 2007 — Four years ago this month, new rules went into effect that restricted the long hours worked by many physicians in training. Now researchers at the Stanford University School of Medicine have shown that the regulations are associated with somewhat lower death rates in high-risk medical patients in teaching hospitals.

The new work hours are not, however, associated with an improved outcome for surgical patients in teaching hospitals.

The study, which will appear in the July 17 issue of the Annals of Internal Medicine, is the largest analysis to date of the impact of work-hour regulations on physicians in training, known as medical residents. It appears alongside a Yale University study in the same issue that found the work-hour regulations improved the medical outcomes for internal medicine patients on three of seven measures.

Medical residents, who total more than 100,000 in the United States, have historically logged long work weeks -- sometimes more than 100 hours. Concern over these long hours began to grow in the mid-1980s, when a New York patient's death was attributed to medical resident error and fatigue. Numerous studies since have found that sleep deprivation among caretakers can cause clinical performance to suffer.

In 2003, the organization that evaluates and accredits medical residency programs in the United States, the Accreditation Council for Graduate Medical Education, enacted new work limits for residents of no more than 80 hours a week or more than 30 hours straight.

By cutting back hours, residents would be required to hand off patients more frequently to other clinical teams. Some worry that important patient details could fall through the cracks in the process, resulting in more medical errors.

After running their analysis, researchers determined that the regulations appeared to benefit medical patients: for every 400 patients admitted to a teaching hospital after the regulations went into effect, there was one fewer death than before. I

The researchers also determined that the regulations did not appear to have an impact on surgical patients, a finding the authors called "striking." Researchers offer several possible explanations: the smaller number of surgical patients may have limited the researchers' power to detect statistically significant differences. It is also possible that any errors due to fatigue may have been offset by transfer-of-care errors, or that the majority of errors occurred during surgery by attending physicians or senior residents - whose hours did not change appreciably under work-hour caps.

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