“Weekday effect” not a factor in elective surgery mortality in Ontario

The day of the week elective surgery is performed in Ontario does not impact a patient’s risk of mortality, according to a new study from the Institute for Clinical Evaluative Sciences (ICES) satellite site in London, ICES Western.

“While previous studies have shown a higher risk of mortality in patients having elective surgery Friday rather than earlier in the week, our data indicates that’s not the case in Ontario,” says Dr. Christopher Vinden, the study’s senior author who is an adjunct scientist at ICES, associate scientist at Lawson Health Research Institute and associate professor of surgery at Western University’s Schulich School of Medicine & Dentistry.

The study examined all adult patients who underwent one of 12 elective daytime surgical procedures during a 10-year period from 2002 to 2012. The researchers included 402,899 procedures performed by 1,691 different surgeons and found no difference in 30-day mortality when Friday was compared with Monday.

“Our data suggests that despite differences in surgeon experience, the risk of 30-day mortality after elective surgery was similar regardless of which day of the week the procedure took place,” says Dr. Luc Dubois, the study’s lead author. Dr. Dubois is an assistant professor at Schulich, associate scientist at Lawson and a vascular surgeon at London Health Sciences Centre.

The researchers found that surgeon experience varied significantly by day of week, with those operating on Fridays having the least experience. Nearly all patients who had their procedure on a Friday had postoperative care on the weekend, while only 49.1 per cent of patients who were operated on a Monday did.

Procedures included were elective surgeries on the esophagus, kidney, pancreas, colon, liver, hip and knee replacements, aortic valve replacements and others. The 12 procedures were chosen because they are commonly only done electively and typically result in at least a two-day hospital stay.

“These results suggest that increased mortality after elective surgery occurring later in the week is not a universal phenomenon across all health care systems. Therefore, should be a correctable issue in those jurisdictions where it occurs,” adds Dubois.

“Association between day of the week of elective surgery and postoperative mortality” was published in the Canadian Medical Association Journal (CMAJ).