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No increase in adverse outcomes for elective day surgery when doctor worked night before: Ontario study


Patients who underwent elective daytime procedures by physicians in Ontario who had provided medical services the night before did not have a higher risk of adverse outcomes than if their physician had not provided medical services the previous night, says a new study from the Institute for Clinical Evaluative Sciences (ICES).

The study, published today in the New England Journal of Medicine, examined the records of almost 40,000 Ontario patients who underwent one of twelve elective daytime surgeries, in both academic and community hospitals.

“Previous studies have looked at fatigue among medical trainees and found that it may affect their performance,” says Dr. Nancy Baxter, chief of general surgery at St. Michael’s Hospital, senior adjunct scientist at ICES, and senior researcher on the paper. “However, this is the first time that such a large-scale study has been conducted on sleep deprivation for staff physicians and surgeons and its impact on patient care, across a range of academic and community hospital settings.”

The researchers looked at outcomes of day surgeries for patients whose physician had treated patients between midnight and 7 a.m. the night before. They then looked at the outcomes of the same number of patients who underwent the same procedure by the same physician, when the physician had not treated patients after midnight. These outcomes included complications, mortality, readmission, length of stay and procedure duration.

“We found no difference in outcomes overall, or when stratified by procedure, physician age or academic status,” says Dr. Anand Govindarajan, the study’s lead author, an adjunct scientist at ICES and surgical oncologist at Mount Sinai Hospital. “Although we cannot quantify the number of hours that a physician was deprived of sleep, it is possible that an attending physician’s greater experience may compensate for performance loss so that clinical outcomes are not affected. More importantly, physicians may be monitoring their own fatigue levels and self-regulating by canceling surgeries or arranging coverage by colleagues if they feel too fatigued to perform surgery safely. They may also be proactively changing their post-call surgical caseload in anticipation of being sleep-deprived.”

“These data suggest that calls for broad-based policy shifts in attending surgeon duty hours and practices may not be necessary at this time,” comments Dr. Baxter. “However, these findings don’t minimize the professional responsibility of every physician to assess whether their individual level of fatigue precludes them from providing proper patient care.”

“Outcomes of daytime procedures performed by attending surgeons after night work,” was published today in the New England Journal of Medicine.

Author block: Anand Govindarajan, David R. Urbach, Matthew Kumar, Brian J. Murray, David Juurlink, Erin Kennedy, Anna Gagliardi, Rinku Sutradhar, Nancy N. Baxter.

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. For the latest ICES news, follow us on Twitter: @ICESOntario

St. Michael’s Hospital provides compassionate care to all who enter its doors. The hospital also provides outstanding medical education to future healthcare professionals in more than 23 academic disciplines. Critical care and trauma, heart disease, neurosurgery, diabetes, cancer care, and care of the homeless are among the Hospital’s recognized areas of expertise. Through the Keenan Research Centre and the Li Ka Shing International Healthcare Education Centre, which make up the Li Ka Shing Knowledge Institute, research and education at St. Michael’s Hospital are recognized and make an impact around the world. Founded in 1892, the hospital is fully affiliated with the University of Toronto.


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