Postoperative outcomes of bariatric surgery performed by trainees: a retrospective single-centre study from a Swiss regional hospital

The involvement of surgical trainees in bariatric surgery remains controversial due to concerns about prolonged operative time and increased complication rates. This study evaluated the impact of trainee participation on postoperative outcomes in a Swiss regional hospital. All bariatric procedures performed between 2014 and 2023 were retrospectively analyzed. Procedures were stratified according to surgeon training level (trainee vs. non-trainee). Operative time, 30-day postoperative complications graded by Clavien–Dindo classification, and length of hospital stay were assessed. Factors associated with postoperative complications were evaluated using bivariate and multivariate logistic regression analyses. A total of 1,232 procedures were included, of which 518 (42%) were performed by trainees. Median operative time was longer in the trainee group (91 vs. 79 min; p < 0.001). Overall postoperative complications (Clavien–Dindo grade II–V) occurred in 4.5% of procedures and did not differ between groups (p = 0.211). In multivariate analysis, trainee involvement was not associated with postoperative complications. Procedures requiring an open approach were strongly associated with postoperative complications. Under structured supervision and adequate case volume, bariatric surgery performed by trainees is safe and yields perioperative outcomes comparable to those of fully trained surgeons, despite longer operative times.