One Anastomosis Gastric Bypass for Severe Obesity in 6,722 Patients: Early Outcomes From the Assuta Surgery Registry

Background: One-anastomosis gastric bypass (OAGB) is an emerging type of bariatric metabolic surgery (BMS). Our study aimed to evaluate the short-term (≤30-day) postoperative safety of OAGB.

Methods: Electronic medical records of all OAGBs performed between January 2017 and December 2021 at a high-volume bariatric center in Israel were scanned using the MDClone software. Data regarding patients' characteristics, surgical procedure, ≤30-day postoperative complications, and their classification according to Clavien-Dindo grade were gathered. Moreover, multivariate logistic regression analysis was used to identify factors related to early postoperative complications after OAGB.

Results: A total of 6,722 patients underwent a primary (74.1%) or revisional (25.9%) OAGB procedure at our institution during the study period. Their preoperative mean age and body mass index (BMI) were 40.6±11.5 years and 41.2±4.6 kg/m2, respectively, and 75.0% were females. Respective mean operating time and length of stay were 67.3±26.6 minutes and 2.2±1.4 days. Complications occurred in 258 patients (3.8%), and include mainly bleeding (n=133, 2.0%), leaks (n=32, 0.5%), and obstruction/strictures (n=19, 0.3%). According to Clavien-Dindo classification, complication rate for grades 1-2 and grades 3a-5 were 1.6%; and 1.4%, respectively. The mortality rate was 0.03% (n=2). The rate of readmission and reoperation were 1.9% and 0.9%, respectively. Age ≥60 years, ≥3 hours of operating room time, and cholecystectomy concomitant with OAGB were independent predictors of early post-OAGB complications.

Conclusions: OAGB was found to be a safe primary and revisional BMS procedure in the ≤30-day postoperative term. The most common early complications were gastrointestinal bleeding (2.0%), leak (0.5%), and stricture (0.3%).