Safety of limb lengthening after Roux-en-Y gastric bypass: an analysis of the MBSAQIP database

Background: Roux-en-Y gastric bypass (RYGB) effectively treats severe obesity, but some patients may require revisional surgery like limb lengthening (LL) for postoperative weight gain. Objectives: This study aims to compare 30-day serious complications and mortality rates between LL and primary RYGB, given limited safety data on LL. Methods: Patients who underwent LL and RYGB were identified from the 2020 and 2021 MBSAQIP databases, the only years in which LL data were available. Baseline characteristics and 30-day rates of serious complications and mortality were analyzed. Results: A total of 86,990 patients underwent RYGB and 455 underwent LL. Patients undergoing RYGB were younger (44.4 versus 49.8 yr, P < .001), had a higher body mass index (BMI) (45.5 versus 41.8 kg/m², P < .001) and higher rates of comorbidities including diabetes (30.0 versus 13.6%, P < .001). RYGB and LL had similar operative duration (125.3 versus 123.2 min, P = .5). There were no statistical differences between cohorts for length of stay (LOS) (1.6 RYGB versus 1.6 LL d, P = .6). After LL, there were higher 30-day rates of reoperation (3.3 versus 1.9%, P = .03) and deep surgical site infections (1.3 versus .5%, P = .03) compared to RYGB. There were no differences in overall serious complications (5.1 LL versus 5.0% RYGB, P = 1.0) and mortality (.2 LL versus .1% RYGB, P = .5). Multivariable logistic regression adjustment found that previous venous thromboembolism was associated with serious complications after LL. Conclusions: When compared to primary RYGB, LL has a favorable safety profile with similar 30-day rates of serious complications and mortality.