Despite new shift rules, surgical residents get about five hours of sleep per day and are frequently fatigued, raising the risk of medical errors, according to a small study in the Archives of Surgery.
For the study, conducted from 2010 to 2011, Harvard researchers questioned 27 orthopedic surgical residents at Massachusetts General Hospital and Brigham and Women's Hospital about their sleeping patterns and asked them to complete daily sleep and work logs for two weeks while wearing an "actigraphy" wristwatch that monitors movements.
They found that:
- Residents averaged 5.3 hours of sleep per day;
- Residents' average sleep levels ranged from 2.8 hours daily to 7.8 hours daily;
- Residents were so fatigued that they reached "impairment" equivalent to be legally intoxicated for 27% of their waking hours; and
- Night-shift residents were more fatigued than day-shift residents.
Based on their fatigue levels, the researchers determined that the residents were 22% more likely to cause a medical error than well-rested physicians. Specifically:
- Residents working the day shift were 19% more likely to make a mistake; and
- Residents working the night shift were 24% more likely to make a mistake.
During the study period, hospitals began implementing new Accreditation Council for Graduate Medical Education residency program requirements that include a maximum shift limit of 16 hours for first-year residents.
According to the study authors, the new shift limits do not do enough to reduce residents' fatigue. "I think that this study suggests that it's more than just regulatory changes," says lead author Frank McCormick.
In an accompanying editorial, Brown University's Thomas Tracy writes that the findings show that "we simply cannot avoid [fatigue] and may have paid lip service to [it] in the past." He recommends targeting fatigued residents for preventive intervention and implementing cultural and process changes within hospitals to discourage sleep deprivation (Seaman, Reuters, 5/21).