P35 GASTROESOPHAGEAL REFLUX DISEASE (GERD) AFTER BARIATRIC SURGERY – EXPLORING THE PATHOPHYSIOLOGICAL MECHANISMS AROUND THE OESOPHAGOGASTRIC JUNCTION

Abstract

Abstract Background It is not uncommon to get de novo GERD after certain types of bariatric surgery. Sleeve gastrectomy (SG), Adjustable Gastric Band ( AGB) and the One anastomosis gastric bypass (OAGB) have been frequently implicated to cause GERD. Roux Y gastric bypass (RYGB) is usually proposed as a curative procedure in patients who develop GERD after a LSG or LAGB. Hypothesis The alteration in mechanics around the Oesophagogastric junction (OGJ) after all types of bariatric surgery predispose to the development of GERD in varying proportions including the RYGB. Aims To theoretically explore the changes around the OGJ in the 4 most common types of bariatric procedures: AGB, SG, OAGB and RYGB Methods and results The following 6 variables that are frequently implicated in causing reflux are equated with each procedure and a score produced to quantify the potential effect on the OGJ. Elimination of the angle of HisInterruption of the Sling fibresInterruption of the Phreno-oesophageal membranePredisposition to the herniation through the hiatus.Effect on the Lower Oesophageal Sphincter residual pressure.Creation of a high-pressure zone below the LES promoting reflux. Based in a standardised technique of performing the 4 common operations, the following scores were obtained. AGB affected 5/6 variables, SG affected 6/6 variables, RYGB affected 5/6 variables and OAGB affected 5/6 variables that influence the antireflux barrier mechanism around the OG junction. Conclusion All bariatric surgeries technically affect the dynamics around the OGJ and indirectly reduce the efficacy of the antireflux barrier mechanisms. The varying contribution of certain individual factors may affect the relative incidence of GERD after surgery after different types of bariatric surgeries. The common recommendation that RYGB serves as a magic bullet against GERD is to be taken in context of the above mechanisms in action.