Laparoscopic One Anastomosis Gastric Bypass (OAGB)/Mini Gastric Bypass (MGB): OAGB Technique

Abstract

One-anastomosis gastric bypass (OAGB) and mini-gastric bypass (MGB) is increasing exponentially worldwide. OAGB was developed in the year 2002. Although it shares some principles with MGB, such as creating only one anastomosis and avoiding an alimentary (Roux) limb, OAGB has progressively introduced several technical concepts and contrasting proposals. Among others, these include: (1) Complete small bowel (SB) measurement to determine biliopancreatic limb (BPL) and common channel (CCh) lengths, which are not fixed but calculated according to total SB length, body mass index (BMI), age, and other metabolic variables; (2) Dissection of the Angle of His and esophagogastric junction (EGJ) membrane with complete visualization of left and right crus and selective hiatoplasty, followed by the creation of a very long and narrow gastric pouch; (3) An anti-reflux mechanism, constructed by an ~10 cm latero-lateral continuous suture between the chosen SB and the distal part of the gastric pouch; and (4) Latero-lateral gastroenteric anastomosis of ~2.5 cm [wider than in Roux-Y Gastric Bypass (RYGB)], but not as wide as inMGB. Applying these measures in a considerable number of patients has resulted in a more robust operation with an excellent balance between safety and efficacy in the long-term outcomes analysis. Some groups perform “hybrid” procedures that include only some of the OAGB principles, and these have also slightly changed through the years. Since outcomes rely highly on its proper performance, this chapter presents a step-bystep description of the standardized current OAGB.