RESUMO
INTRODUCTION: The purpose of this study is to investigate the occurrence of thermal injury in the extrahepatic bile ducts when monopolar electrosurgery is used to perform dieresis of the cystic duct and cystic vessels in laparoscopic cholecystectomy. METHODS: Female pigs (n=40) of the Large White breed were separated into 2 groups of 20 animals. In the experimental groups, dieresis of the cystic duct and cystic vessels was performed with monopolar electrosurgery using a hook-like dissector using a power setting of 20 W, whereas in the control group this procedure was performed with a pair of Metzenbaum scissors disconnected from any kind of thermal energy source. Occurrence of distal thermal injury was evaluated on 2 occasions, on the 3rd and 28th days postoperatively. It consisted of exploratory laparotomy, cholangiography and both macroscopic and microscopic examination of the surgical specimen, which included cystic duct stump, hepatic duct and choledochus. RESULTS: The presence of distal thermal injury, classified as second degree, 1.2 mm in the portion near the clipping area, was observed in only one of the cystic duct stumps after microscopic examination, without statistical significance. No thermal injury was observed in the extrahepatic bile ducts. CONCLUSIONS: Monopolar electrosurgery produced negligible thermal injury in the extrahepatic bile ducts after laparoscopic cholecystectomy.
