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Study finds surgeons with modest sleep deprivation do not have more complications during surgeries


Lack of sleep is associated with impaired performance especially in simple, repetitive tasks and has led to controversial work hour restrictions on surgeons in training to prevent medical errors. But new research by the Institute for Clinical Evaluative Sciences (ICES) Western and Lawson Health Research Institute shows that the safety of one of the most common surgical procedures is unaffected by modest sleep deprivation.

“We know that modest sleep deprivation has an effect, that the effect is maximal in mundane and monotonous tasks such as driving, but has less effect on cognitively challenging tasks. Whether disrupted sleep has an effect on complex tasks such as surgery is not clearly defined. We deliberately selected gall bladder surgery for this study because it is the most common general surgical operation done in Ontario and most general surgeons would consider it to be fairly straightforward. We felt that its ‘mundaneness’ would maximize the probability of demonstrating a signal of the adverse impact of sleep deprivation if it exists,” says lead author Dr. Christopher Vinden, an experienced surgeon at London Health Sciences Centre and associate professor of surgery at Western University.

The study, published today in JAMA, is the first population-based study to examine the association between surgeons operating the night before a major elective surgery and patient outcomes. The findings show no higher risk of complications of daytime elective cholecystectomy when a surgeon did (vs. did not) operate the night prior.

The population-based, matched, retrospective cohort study examined 94,183 elective daytime (started between the hours of 7 a.m. and 6 p.m.) laparoscopic cholecystectomies performed by a surgeon on a non-holiday weekday between April 1st, 2004 and March 31st, 2011 in Ontario.

Of these surgeries, there were 2,078 procedures where 331 different surgeons across 102 community hospitals had operated between midnight and 7 a.m. the night before. Each “at-risk” surgery was randomly matched to four other elective laparoscopic cholecystectomies performed by the same surgeon where there was no evidence they had operated the night before.

No significant associations were found in conversion rates to open operations, complications due to surgery, or death between surgeons operating the night before compared with when they did not operate the previous night.

“These findings are reassuring because they do not support safety concerns related to surgeons operating the night before performing elective surgery. Restructuring healthcare delivery to avoid surgeons operating during the day after they operated at night would have important cost, staffing and resource implications. One estimate is that healthcare costs could increase by over $1-million per life saved if all physicians were constrained by work hour restrictions. In some rural under serviced areas restricting surgeon work hours may not be possible without reducing access to care in these settings,” says Danielle Nash, a co-author on the study and an epidemiologist at ICES Western.

The study “Complications of daytime elective laparoscopic cholecystectomies performed by surgeons who had operated the night before” is in the current issue of JAMA.

Authors: Christopher Vinden, Danielle M Nash, Jagadish Rangrej, Salimah Z Shariff, Stephanie N Dixon, Arsh K Jain, Amit X Garg.

ICES is an independent, non-profit organization that uses population-based health information to produce knowledge on a broad range of healthcare issues. Our unbiased evidence provides measures of health system performance, a clearer understanding of the shifting healthcare needs of Ontarians, and a stimulus for discussion of practical solutions to optimize scarce resources. ICES knowledge is highly regarded in Canada and abroad, and is widely used by government, hospitals, planners, and practitioners to make decisions about care delivery and to develop policy.

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Lawson Health Research Institute. As the research institute of London Health Sciences Centre and St. Joseph's Healthcare London, and working in partnership with Western University, Lawson Health Research Institute is committed to furthering scientific knowledge to advance healthcare around the world. www.lawsonresearch.com


  • Julia Capaldi
  • Communications & Public Relations, Lawson Health Research Institute
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