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 2 (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 2 (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. Graphical abstract