It is surprisingly common for surgical residents to be fatigued, adding to concerns about how long hours and nighttime shifts could contribute to serious medical mistakes, a new study shows.
"This study is the first to quantify resident surgeon fatigue and its predicted risk for error," said study co-author Dr. Frank McCormick, of Harvard Combined Orthopedic Residency Program and Massachusetts General Hospital. "Fatigue levels were higher than anticipated, especially on the night float rotation."
The results, published in the Archives of Surgery Monday, state that on average, surgical residents were functioning at less than 80 percent of their full mental capacity nearly half of the time they were awake.
To get that data, researchers gave 27 orthopedic surgical residents watch-like instruments that measured both sleep and activity, as well as mental fatigue. The physicians in training averaged a little more than five hours of sleep per day, although individual amounts fluctuated from more than seven hours to less than three.
The prevalence of fatigue was high.
Overall, residents functioned at less than 80 percent of their full mental capacity due to fatigue almost half of the time they were awake, and were at less than 70 percent mental effectiveness nearly 30 percent of the time.
Notably, so-called "night-float" rotations led to higher levels of fatigue than day-shift rotations, despite the fact that the shift was designed to keep hospitals staffed through the night while complying with requirements that limit the number of hours residents can work. Residents have an 80-hour weekly limit (averaged over four weeks), and cannot work more than 24 hours at a time -- measures the Accreditation Council for Graduate Medical Education adopted in light of staff services and cuts that put additional pressure on residents, making programs more rigorous than ever.
In commentary on the new study, also published in the Archives of Surgery, Dr. Thomas Tracy Jr., pediatric surgeon-in-chief at the Hasbro Children's Hospital in Rhode Island, said the fact that fatigue is common is not startling, "but its pervasiveness is a finding we simply cannot avoid and may have paid lip-service to in the past."
Dr. Jeffrey Rothschild, a professor of sleep medicine at Harvard University who was not associated with the new research, in 2009 authored a study that found surgical procedures performed the day after an attending surgeon or OB-GYN worked overnight were not tied with significantly higher complication rates. However, there was an increased risk of complications in surgical procedures done during the night by doctors who'd slept fewer than six hours.
"It's been a concern for many years," he said.
McCormick stressed that in the current study, no actual errors were recorded; researchers were simply measuring the risk of error. He added that simply changing hours by eliminating the night shift can make a clear, measurable difference. McCormick's next step is to see how using devices monitoring sleep and fatigue could be adopted by hospitals in order to make changes before any problems arise.
But what this means for patients right now remains murky.
"What you'd like to be able to say to your surgeon in the morning is, 'Did you get a good night's rest?' The question is, "What happens if the answer is that they didn't?'" said Rothschild. "It's a great question, and right now there's no simple answer."