No Weekday Effect in Bariatric Surgery-a Retrospective Cohort Study

Purpose Major abdominal surgery carried out in the later part of the week has been associated with increased complication rates. The aim of this study was to explore whether the weekday of surgery affects the 30-day complication risks after primary Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG). Material and Methods Prospectively collected data, extracted from the Scandinavian Obesity Surgery Registry (SOReg), of all patients who underwent primary laparoscopic RYGB or SG between 2010 and 2017 were included in this retrospective cohort study. Multivariate logistic regression adjusted for differences in case-mix and operating center by weekday of surgery. Results In total, 49,349 patients were included in this study. The overall 30-day complication rate was 7.2% (n = 3574), whereof 2.9% (n = 1428) had a severe complication, i.e., requiring intervention in general anesthesia or more. The 30-day mortality rate and readmission rate were 0.02% (n= 12) and 7.6% (n= 3726), respectively. The highest overall complication rate was seen in patients operated on Wednesdays and Thursdays (7.7%), while severe complications were most common on Wednesdays (3.3%). However, a large variation in severe complications was seen between centers, from 0.4 to 8.0%. After adjustment for case-mix and operating center, there was no significant increased risk of overall complications, severe complications, or readmission rates by weekday of surgery, except for a lower readmission rate in patients operated on Tuesdays. Conclusion The result of the present study supports the notion that bariatric surgery can be performed safely on all weekdays.