From one-anastomosis gastric bypass to Roux-en-Y gastric bypass: causes and postoperative complications of a single center study

Introduction: Bariatric surgery emerges as a rapid and effective solution for obesity and its related co-morbidities. With long-term follow up for one-anastomosis gastric bypass (OAGB), several complications arise that might necessitate surgical correction including revision to normal anatomy or conversion to either RYGB or sleeve gastrectomy. Methods: Between June 2020 to June 2022, we retrospectively reviewed medical records of patients who had OAGB at our institution later had conversion to RYGB. Exclusion criteria included if less than 18 years old, had previous upper gastrointestinal surgeries other than OAGB, Contraindications for abdominal insufflation and not fit for general anesthesia, Primary study objective was causes of conversion of OAGB to RYGB. Results: Sixty-five patients were included. Several indications for conversion to RYGB exist; however, predominant cause was biliary reflux n=28 (43.1%) followed by marginal ulcer n=20 (30.8%).Two patients had surgical site infection. Four patients had respiratory tract infection. Two patients had intraluminal bleeding while one patient had intrabdominal (extraluminal bleeding). Both patients were managed conservatively.one patient had jejuno-jejunal anastomotic site stricture that was managed by surgical revision. One patient had anastomotic leakage with localized collection drained percutaneously. Difference between weight and BMI before undergoing RYGB and 1 year after follow-up were evaluated. Weight and BMI after 1 year were statistically lower compared to weight (115.2±16.5 vs 89.8±11.25, p=0.0001) and BMI (35.8±4.69 vs 27.9±3.18, p=0.0001) before RYGB. Conclusion: Laparoscopic conversion to RYGB from OAGB is a safe effective surgical procedures with a low rate of complications.