Impact of body mass index on perioperative outcomes of laparoscopic major hepatectomies

Abstract

Background: Data on the effect of body mass index on laparoscopic liver resections are conflicting. We performed this study to investigate the association between body mass index and postoperative outcomes after laparoscopic major hepatectomies. Methods: This is a retrospective review of 4,348 laparoscopic major hepatectomies at 58 centers between 2005 and 2021, of which 3,383 met the study inclusion criteria. Concomitant major operations, vascular resections, and previous liver resections were excluded. Associations between body mass index and perioperative outcomes were analyzed using restricted cubic splines. Modeled effect sizes were visually rendered and summarized. Results: A total of 1,810 patients (53.5%) had normal weight, whereas 1,057 (31.2%) were overweight and 392 (11.6%) were obese. One hundred and twenty-four patients (3.6%) were underweight. Most perioperative outcomes showed a linear worsening trend with increasing body mass index. There was a statistically significant increase in open conversion rate (16.3%, 10.8%, 9.2%, and 5.6%, P