For many of us, college was the last time we "pulled an all nighter." For medical interns, however, staying up all night is as common as finding a television re-run of ER.

Dr. David Andorsky, a resident at Brigham and Women’s Hospital, explained, "I go home and collapse and take a nap. For interns, it is a way of life. I am very aware of how much sleep I’m getting."

For a long time it has been accepted as part of the job - until a recent landmark study at Brigham and Women's Hospital, published this October in the New England Journal of Medicine.

The study's objective was to quantify trainees' work and sleep hours and validate The Accreditation Council for Graduate Medical Education (ACGME)'s recent limit on work hours for U.S. medical residents.

When Harvard researchers limited work periods for interns to a maximum of 24 hours and held work weeks to 80 hours, significantly fewer patient medical errors occurred than for interns who worked longer, more traditional shifts and weeks with more work hours.

In a second study of 20 interns, the Harvard researchers found that those working the longer, traditional shifts got less sleep per week than when they worked on a more restricted schedule. When the interns were on the restricted work reschedule (less work, more sleep), they had "less than half of the rate of attentional failures while working on-call nights."

Dr. Andorsky, who participated in the study, acknowledged a big difference working on the modified schedule. "I felt more excited to be there, awake and alert." The studies were conducted among first year interns in intensive and coronary care units where, presumably, intern alertness would be at a premium.

Dr. Charles Czeisler, an author of the study, explained, "The key issue that we looked at is whether it is appropriate or safe to have interns work 30 hours in a row rather than focusing on the total number of hours they worked in a week. We found that the 30 hour shift is the Achilles heal of the medical education system in the United States, having an impact on the patient's safety and medical education.

"The work hour regulations are set at 80 hours a week. It isn't just a matter of cutting work hours and increasing sleep. You need to time the schedules appropriately to allow people to sleep at the correct circadian time without having too much time awake."

Brigham and Women's Hospital in Boston has begun implementing a new policy based on this research that regulates the shifts of first year interns by restricting:

• Work to 80 hours or less per week;
• Shifts to 24 hours or less
• Assignments so that after 18 hours of continuous work interns cannot write orders for patient care activities.

When asked about the experience, Dr. Andorsky said, "It is brave to open up your ICU to scrutiny and errors. The findings apply to all ICUs in the country. Patient safety and resident work hours are critically important. It isn't all about work hours. Doctors need to be awake and informed."

This article was published in the Winter 2005, Volume 7, Issue 1 of sleepmatters.