Related Experiment Video
Updated: Jul 6, 2025

One-anastomosis Gastric Bypass OAGB in Rats
Published on: November 10, 2018
One Anastomosis Gastric Bypass as Revisional Surgery Following Sleeve Gastrectomy: A Systematic Review and
Hayato Nakanishi1,2, Kamal Abi Mosleh3, Mohammad Al-Kordi3
1St George's University of London, London, SW17 0RE, UK.
Background:
Although sleeve gastrectomy (SG) is the most performed metabolic and bariatric surgery (MBS) worldwide, some patients require conversional procedures due to weight recurrence or late complications. Recently, one-anastomosis gastric bypass (OAGB) gained popularity as a viable option to address those problems. The aim of this meta-analysis is to assess the safety and efficacy of conversional OAGB after primary SG in the management of patients with obesity.
Methods:
Cochrane, Embase, PubMed, Scopus, and Web of Science were searched for articles from their inception to February 2023 by two independent reviewers using the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) system. The review was registered prospectively with PROSPERO (CRD42023403528).
Results:
From 1,117 studies screened, twenty studies met the eligibility criteria, with a total of 1,057 patients with obesity undergoing conversional OAGB after primary SG. The mean age ranged from 28.2 to 49.5 years, and 744 patients (75.2%) were women. At one year after revisional OAGB, the pooled mean percent excess weight loss (%EWL) was 65.2% (95%CI: 56.9, 73.4, I2 = 97%). The pooled mean %EWL after conversional OAGB was 71.1% (95%CI: 62.2, 80.0, I2 = 90%) at two years and 71.6% (95%CI: 61.0, 82.2, I2 = 50%) at five years. Additionally, resolution rates of diabetes and hypertension were 65.4% (95%CI: 0.522, 0.785, I2 = 65%) and 58.9% (95%CI: 0.415, 0.762, I2 = 89%), respectively.
Conclusions:
Our meta-analysis demonstrated OAGB as an effective conversional procedure after primary SG in terms of weight loss and obesity-associated medical problems for selected patients. Despite the promising results, further randomized controlled studies with larger sample sizes and more extended follow-up periods are necessary to determine if the OAGB is the best conversional surgery after SG.
Related Concept Videos
Peptic Ulcer Disease V: Surgical Management and Nursing Care
Surgical Interventions for Peptic Ulcer Disease
Inflammatory Bowel Disease V: Surgical Management
Here are some common surgical interventions for IBD:

