Resident study: Hours worked do make a difference

Medicine mulls a trade-off between a reduction in medical errors and less time for medical training.

By Myrle Croasdale, AMNews staff. Dec. 6, 2004.

During his first year at Brigham and Women's Hospital in Boston, every medical mistake Christian Ruff, MD, and his fellow interns made in the intensive care unit was tracked as part of the Harvard Work Hours, Health and Safety Study.

Although most mistakes were caught before patients were harmed, the mistakes themselves were preventable, researchers say, because it was primarily fatigue that caused the interns to make them.

Two studies, one measuring the impact of sleep deprivation on medical errors, the other examining how much interns slept and how often they nodded off while on duty, were recently published in the New England Journal of Medicine.

Some physician leaders say the studies vindicate the time limits placed on all residents a year and a half ago. Others say the amount of improvement in patient safety might not justify the cost to resident education. But all agree that the data provide fresh reason to re-evaluate patient care and the hours all physicians, not just residents, work.

For one of the studies, interns worked an average of 80 hours a week, with call periods of 24 hours and longer, then switched to a schedule of 63 hours a week, with call limited to 16 hours.

The interns made 36% more serious medical errors while working the longer schedule than during the shorter one. They also made twice as many serious diagnostic errors when working longer hours.

Ironically, the 80-hour schedule was put into place just 18 months ago in an effort to improve conditions for both patient and resident safety, the researchers noted.