Conversion of One Anastomosis Gastric Bypass to Roux-en-Y Gastric Bypass: Results of a Retrospective Multicenter Study.

Background: One anastomosis gastric bypass (OAGB) may expose the patient to certain specific complications. Here, we report the results of conversion of OAGB to Roux-en-Y gastric bypass (RYGB) in terms of outcomes and weight loss.

Methods: Between January 2009 and January 2019, all patients undergoing conversion of OAGB to RYGB because of complications due to OAGB (n = 23) were included. The primary efficacy endpoint was the effectiveness of converting OAGB to RYGB. The secondary endpoints were overall mortality and morbidity during the first 3 postoperative months, specific morbidity, reoperation, length of hospitalization, weight loss, and progression of comorbidities related to obesity at 2-year follow-up.

Results: Indications for conversion were bile reflux (n = 14; 60.9%), severe malnutrition (n = 3; 13%), gastro-gastric fistula (n = 4; 17.4%), and anastomotic leak (n = 2; 8.7%). The median time interval between OAGB and conversion to RYGB was 34 months (0-158). At the time of RYGB, median body mass index (BMI) was 28.0 kg/m (18.2-50.7), representing a median BMI change of 14.0 (- 1.7-43.5). Fifteen surgeries (65.1%) were completed laparoscopically. Five complications (21.7%) were recorded, including 2 major ones (8.7%). Reoperation rate was 4.3% (n = 1). At 24 months of follow-up (n = 18; 78.3%), median BMI was 28.7 kg/m (19.4-35.4), representing a median BMI change of 19.5 (12.2-43.1). No patient complained of bile reflux or persistent malnutrition.

Conclusion: RYGB performed as revisional surgery for complications after OAGB is an effective procedure with no major weight regain at 2 years of follow-up.