Transit Bipartition After Sleeve Gastrectomy

Patients previously undergoing sleeve gastrectomy and followed at the bariatric/gastrosurgery clinic of Hospital das Clínicas de Ribeirão Preto will be enrolled consecutively after informed consent. Baseline assessments include medical-record review, anthropometry, GERD-HRQL, upper gastrointestinal endoscopy, high-resolution esophageal manometry, 24-hour esophageal pH monitoring, CT gastric volumetry, solid-meal gastric emptying scintigraphy, metabolic and hormonal testing, and stool collection for microbiota and fecal elastase analyses. Transit bipartition will create a side-to-side gastroileal anastomosis and a distal side-to-side ileoileal anastomosis while preserving pyloric and duodenal transit. Selected paired assessments will be repeated at 6 months. Body weight and comorbidities will be followed at 3, 6, 9, and 12 months, and upper gastrointestinal endoscopy will be repeated at 12 months to assess the mature gastroileal anastomosis. The target of 40 participants is expected to provide 34 complete baseline and 6-month T½ pairs after allowance for 15% attrition.