Imagine yourself as a hospital patient. Your doctor walks in and lets out a long yawn. When you ask why he is so tired, he admits to working nonstop for the last 24 hours. He says that he works these marathon shifts many times a month.
Should you be concerned for your safety?
Increasing evidence suggests yes. Physicians who work marathon shifts -- those longer than 24 hours -- can cause real harm to patients, according to new research.
And physicians themselves say long hours can be detrimental to their performance.
"I have far too many memories of looking up the wrong drugs and catching myself just in time, of staring blankly at a nurse when asked to make a decision, of forcing friends to talk to me on the cell phone the whole way home so I wouldn't fall asleep at the wheel," said Dr. Jenny Blair, an emergency medicine resident at the University of Chicago.
"I have forgotten things, poked myself with a needle during a laceration repair," recalled Dr. Jeanette Hammerstein, an emergency room doctor at Hackley Health Care in Muskegon, Mich.
In a large study published in this week's issue of the journal Public Library of Science Medicine, researchers suggest that when doctors work five or more marathon shifts in a month, they are seven times more likely to make errors that harm patients -- and four times more likely to make errors that result in patient deaths.
"These marathon shifts, anytime that happens, is dangerous," said Dr. Charles Czeisler, chief of the division of sleep medicine at Brigham and Women's Hospital in Boston, and senior author of the study.
Researchers conducted a Web-based survey across the United States, in which 2,737 first-year doctors from different specialties completed 17,003 confidential monthly reports.
The study also found that these first-year doctors were more likely to fall asleep during rounds -- and even surgery -- when they worked five or more marathon shifts in a month.
Blair and Hammerstein aren't the only doctors who report that sleep deprivation has affected their performance.
"What I do remember is being bone-tired at 6 in the morning as I began a new day after being awake since 5 the previous morning. It's a horrible feeling that can make you cranky and angry," said Dr. Scott Terranella, at the University of Massachusetts in Worcester, Mass.
Dr. Amy Hennessy, of Virginia Commonwealth University School of Medicine, said marathon work hours made her a "more angry and emotional person."
"There were several days when I would get home and just start crying for the smallest reasons, or would just feel angry at my patients when they hadn't done anything wrong," said Hennessy.
There have been efforts to address the problem. In 2003, the Accreditation Council for Graduate Medical Education set work-hour limits for all residents -- doctors completing their specialty training -- in the United States. These regulations limit residents to work a maximum of 30 hours nonstop per shift and no more than 80 hours a week.
But the regulations still allow residents to work two 30-hour shifts a week and up to nine 30-hour shifts a month.
While evidence mounts that marathon work hours increase medical errors and cause patients harm, not everyone agrees that work hours should be shortened. Some doctors argue that long shifts are essential for continuity of patient care.