Laparoscopic sleeve gastrectomy to Roux-en-Y gastric bypass conversion versus primary Roux-en-Y gastric bypass: a propensity score matching analysis

Background: Secondary bariatric surgery rates have increased, accounting for approximately 19% of the total bariatric cases in the last years, most commonly conversion of sleeve gastrectomy to gastric bypass. Using the MBSAQIP, we evaluate the outcomes of this procedure compared to the primary RYGB surgery.

Methods: The new variable, conversion of sleeve gastrectomy to RYGB in the 2020 and 2021 MBSAQIP database was analyzed. Patients who underwent primary laparoscopic RYGB and those who underwent laparoscopic sleeve gastrectomy to RYGB conversion were identified. Using Propensity Score Matching analysis, the cohorts were matched for 21 preoperative characteristics. We then compared 30-day outcomes and bariatric-specific complications between primary RYGB and conversion from sleeve gastrectomy to RYGB.

Results: There were 43,253 primary RYGB procedures performed and 6,833 conversions from sleeve gastrectomy to RYGB. The matched cohorts (n = 5912) for the two groups have similar pre-operative characteristics. Propensity-matched outcomes showed that conversion from sleeve gastrectomy to RYGB was associated with more readmissions (6.9% vs 5.0%, p < 0.001), interventions (2.6% vs 1.7%, p < 0.001), conversion to open (0.7% vs 0.2%, p < 0.001), length of stay (1.79 ± 1.77 days vs 1.62 ± 1.66 days, p < 0.001), and operative time (119.16 ± 56.82 min vs 138.27 ± 66.00, p < 0.001). There were no significant differences in mortality (0.1% vs 0.1%, p = 0.405), and bariatric-specific complications such as anastomotic leak (0.5% vs 0.4%, p = 0.585), intestinal obstruction (0.1% vs 0.2%, p = 0.808), internal hernia (0.2% vs 0.1%, p = 0.285) or anastomotic ulcer (0.3% vs 0.3%, p = 0.731) rates.

Conclusion: Conversion from sleeve gastrectomy to RYGB is a safe and feasible operation with reasonable outcomes compared with primary RYGB.