Development, standardization, and evaluation of NOTES cholecystectomy using a transsigmoid approach in the porcine model: an acute feasibility study.

BACKGROUND: Transluminal cholecystectomy is feasible. However, the procedure is time consuming, difficult, and poorly standardized so far. In the present study we therefore aimed to further evaluate and optimize a transsigmoid approach for cholecystectomy with minimal transabdominal assistance in the porcine model.
METHODS: After a pilot series of 6 pigs, NOTES (natural-orifice transluminal endoscopic surgery) cholecystectomy was performed in a standardized manner in another 12 pigs. A transsigmoid approach was applied via a specially designed trocar (ISSA) with a double-channel gastroscope advanced into the peritoneal cavity. After identification of the infundibulum, the cystic duct and artery were closed by application of hemostasis clips. After dissection of these structures, the gallbladder was separated from the liver by electrocautery following injection of isotonic saline solution. A grasper introduced through a modified Veress needle (initially used for establishing the hydroperitoneum) and an additional transcutaneous stay suture were used to ease preparation of the gallbladder.
RESULTS: Transluminal cholecystectomy was successfully performed in all animals. No serious acute complications occurred; minor bleeding in 4 out of 12 cases (1 cystic artery and 3 liver parenchyma) was successfully handled by electrocautery. Clip application to close the cystic duct and artery resulted in complete sealing. Standardization of the procedure was associated with a significant decrease in total operating time (113.3 +/- 31.8 minutes for the first 6 pigs and 73.6 +/- 17.2 minutes for the last 6 pigs).
CONCLUSIONS: In pigs with a healthy gallbladder, our standardized technique of transsigmoid cholecystectomy could be performed relatively fast with acceptable complication rates at this level of evolution, as shown in these acute experiments.