Gastric bypass Technical aspects and long-term results

Sima, E. 2017. Gastric bypass. Technical aspects and long-term results. Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Medicine 1324. 67 pp. Uppsala: Acta Universitatis Upsaliensis. ISBN 978-91-554-9889-4. Roux-en-Y gastric bypass (RYGBP) achieves superior shortand long-term weight loss compared to other weight loss modalities. Different operative techniques have been developed to technically facilitate the surgical procedure, with consequences in the form of an array of postoperative complications and gastrointestinal symptoms. Furthermore, as our follow-up on operated patients extends beyond the first postoperative years, it becomes apparent that a significant number of patients experience unsatisfactory weight result. Current research is just starting to chart factors associated with postoperative long-term weight regain with the ultimate goal of preventing it. In Paper I it is found that the linear stapled technique for the gastrojejunostomy in laparoscopic RYGBP is associated with shorter operative time, in-hospital stay and a lower incidence of surgical site infections and anastomotic strictures compared to the circular stapled technique. Paper II demonstrates that, despite no differences in weight result, the 21-mm circular stapled technique for the gastrojejunostomy is associated with a higher incidence of vomiting and endoscopic anastomotic dilatations compared to the 25-mm circular stapled technique and the linear stapled technique in the long-term after RYGBP. Paper III shows that despite differences in body composition, long-term weight responders and non-responders after RYGBP did not differ in resting, glucose-induced or activity-related energy expenditure. Lastly Paper IV shows long-term weight result is associated with fasting levels of leptin and ghrelin, and that the response of these hormones to a glucose load might contribute to perpetuate obesity. Eduardo Sima, Department of Surgical Sciences, Akademiska sjukhuset, Uppsala University, SE-75185 Uppsala, Sweden.