Randomized Trial Comparing Gastric Bypass With and Without Cholecystectomy

We suggest performing a prospective randomized pilot trial comparing RYGB without concomitant cholecystectomy with RYGB with concomitant cholecystectomy for patients with absence of gallstones in preoperative ultrasound. Patients with ultrasonographically confirmed gallstones in the gallbladder undergo concomitant cholecystectomy at time of RYGB and are excluded from the study.Patients who meet the inclusion criteria will be randomized according to a randomization list generated by the CRC of the University Hospital of Geneva. The randomization envelops will be opened by the study staff at the appropriate time prior to the scheduling of gastric bypass after subject selection. The randomization assignment insert will contain information specifying whether the cholecystectomy will be performed or not during gastric bypass procedure.

A total of 90 consecutive obese patients attending the Unit of Visceral Surgery of the University Hospital of Geneva who meet the criteria for bariatric surgery and where the preoperative ultrasound confirms absence of gallstones will be recruited for the study.

A prospective open randomized pilot study design will be used. At 6 follow-up visits (at discharge, 1 ,3 ,6 ,12 and 18 months post-surgery), patients will be evaluated.

This study will be conducted in compliance with the protocol, the current version of the Declaration of Helsinki, the ICH-GCP or ISO EN 14155 as wella s all national legal and regulatory requirements, the LPth (Loi sur les produits thérapeutiques 812.21) and the OClin (Ordonnance sur les essais cliniques des produits thérapeutiques 812.214.2).

Description of surgical technique One optical trocar, three 12 mm trocars and one 5 mm trocar are placed. No additional trocar has to be placed for concomitant cholecystectomy. The intervention will start with the cholecystectomy laparoscopically. A small gastric pouch (around 20-30 cc) is created using blue cartridge staplers. A standard robotic RYGB with a 75 cm biliary limb and a 150 cm antecolic alimentary limb is performed. A hand-sewn gastrojejunal and jejunojejunal anastomois are performed, using a single layer running suture of Vicryl 2.0.

Data Collection:

Pre-Operative demographic data and other variables will be collected at baseline and at some of the 6 follow-up points (at discharge, 1,3,6,12,18 months):

Ultrasound, Patient Demographics and pre-Operative History will be collected, including: Gender, age on admission for operation, BMI, Height, Weight, ASA score, history of abdominal surgery, co- morbidities (Type 2 diabetes requiring Insulin or oral medication), Hypertension requiring medication, Coronary heart disease, including history of myocardial infarction, angina pectoris, coronary artery surgery Pulmonary comorbidities including history of pulmonary embolism, Sleep Apnea Tobacco use, Medication used by patient, Systolic and diastolic blood pressure, heart rate, Fasting plasma glucose, HbA1c, laboratory findings, QOL using the EQ-5D-5L questionnaire

Intra-Operative Assessment: Intra-Operative data such as complications (organ lesion, bleeding, conversion), operative time, docking times, estimated blood loss will be collected

Post-Operative Assessment: From surgery to discharge, the following patient information will be collected: complications according to Clavien/Dindo Classification system, re- operation, re-admission, length of hospital stay

Our hypothesis is that the approach without cholecystectomy would be superior in terms of a decrease of perioperative adverse events and postoperative complications, as well as lenght of operation, lenght of hospital stay, overall costs with a very low risk of biliary complication in the follow up.