In the June 6, 2006, issue of the Annals of Internal Medicine, researchers from the University of Chicago report that although average sleep time for interns in the study increased only modestly -- by about one hour -- the interns felt that even small gains in sleep led to substantial improvements in fatigue, sleep quality and ability to care for their patients.
"This is a proven method of alleviating fatigue in industries that combine high intensity with long shifts," said study director Vineet Arora, M.D., instructor of medicine at the University of Chicago, "yet is has been neglected by the one industry that studies sleep. Our results show that a well timed nap can provide a significant boost in physician concentration and take away some of the burden of chronic sleep deprivation."
The researchers studied 38 first-year medical residents (also known as interns) on the general medicine service at the University of Chicago Hospital from July 2003 to June 2004. For several month-long periods during that year, the interns were on-call every fourth night. Interns on-call often work a 30-hour shift, consisting of a full day, then a night on-call, followed by a shorter day. Each intern wore an "Actiwatch" for the entire month, which recorded his or her movements around the hospital, time in bed and time asleep.
For two weeks out of each month on-call, interns followed the standard schedule, grabbing a little sleep whenever they could during the night shift. For the other two weeks they had access to protected time, allowing them to nap. Those on the nap schedule were "strongly encouraged" to forward the care of their patients to a designated "night-float" resident who would cover for them between midnight and 7 a.m.