A murine model of laparoscopic-assisted intervention

Background: In order to better investigate the effects of laparoscopic surgery, it is necessary to establish reliable, reproducible, and economical animal models of laparoscopic intervention. Here we describe a mouse model of laparoscopic-assisted colon resection. Methods: After successful induction of anesthesia the mouse is placed in Trendelenburg position and the peritoneal cavity is insufflated with carbon dioxide gas through an angiocatheter placed in the right upper quadrant. A 4-mm rigid scope with camera attachment is then inserted through a midline port created just caudal to the xiphoid. A second port is then created in the right lower quadrant to allow introduction of laparoscopic forceps into the peritoneal cavity. The cecum, which extends 1.5 cm beyond the ileocecal valve, is grasped with forceps and exteriorized through the operative port. Extracorporeally, the cecum is ligated and resected before the cecal stump is returned to the peritoneal cavity. The abdominal wall defects are then stapled closed. Results: This simple model can be mastered by individuals with very limited surgical experience. This laparoscopic model has been used successfully in our laboratory in a number of experiments with an intraoperative complication rate of 3.2% (3/94), which was similar to the open surgery group rate of 2.1% (2/95, p= 0.99 by chi square). We observed no postoperative leaks in either group. The only postoperative death occurred in the open resection group due to dehiscence of the laparotomy wound. Conclusions: We propose that this model may be useful for comparing the effects of open to laparoscopic surgery. Received: 19 June 1996/Accepted: 2 November 1996