Robotically assisted minimally invasive biliary surgery in aporcine model

Abstract

Background: A robotic surgery system has the potential both to reduce the effects of tremor and fatigue and to enhance dexterity in the performance of complex, fine endosurgical tasks. We report a prospective study of robotically assisted minimally invasive biliary surgery in a porcine model using the Zeus robotic surgical system (Computer Motion, Goleta, Ca, USA). Methods: For this study, 50-kg domestic swine were used. Minimally invasive robotically assisted cholecystectomy was performed in 16 animals, either longitudinal or transverse common bile duct incision, T-tube placement, and suture repair of the common bile duct. Retrieval of 12 simulated bile duct calculi was attempted. Eight animals were monitored for 6 weeks postoperatively. Liver function tests and cholangiography were performed 2 and 6 weeks after surgery. Results: The median setup time for the robotic system was 45 min (range, 10-120 min). The median operative time was 40 min (range, 25-60 min) for cholecystectomy and 80 min (range, 40-165 min) for bile duct dissection, exploration, and repair. Of 12 bile duct calculi, 11 were retrieved successfully. Cholangiography demonstrated no leaks, and the anastomotic stenotic index (diameter of the proximal bile duct divided by the diameter of distal bile duct) at 6 weeks was 0.98. The results of the liver function tests remained normal in all animals. One postoperative death unrelated to operative technique occurred. Complications included one minor splenic laceration and two intraoperative gallbladder perforations. Conclusions: Robotically assisted minimally invasive biliary surgery in this animal model is both feasible and safe. The Zeus system provides enhanced dexterity, which facilitates precise laparoscopic suture repair of small bile ducts.