Carbon dioxide pneumoperitoneum prevents intraperitoneal adhesions after laparotomy in rats

Abstract

Purpose: The aim of this study was to assess whether carbon dioxide insufflation (CDI) pneumoperitoneum prevents intraperitoneal adhesions (IPAs).

Methods: Laparotomy was performed in 40 8-week-old Lewis rats and their bowels delivered through the wound and manipulated. The rats were divided into 4 groups, namely, those that would have laparotomy (Lp group, n = 15), Lp with CDI (Lp-CDI group, n = 15), Lp and bowel anastomosis (LpBA group, n = 5), and LpBA with CDI (LpBA-CDI group, n = 5). LpBA and LpBA-CDI group rats had 1 cm of ileum excised and end-to-end anastomosis performed. To accelerate IPA formation, all rats then had their bowels heated to 45 degrees C for 40 seconds and 0.5 mL of Lewis rat blood spilled over them. Rats in the control group (n = 5) had Lp alone without heating or blood spillage. Pneumoperitoneum involved insufflating carbon dioxide into the peritoneal cavity through a cannula at the time of final abdominal closure to create pneumoperitoneum to a pressure of 5 mm Hg. All rats had relaparotomy 10 days after surgery and IPAs were assessed blindly using an IPA severity score (IPASS: 0 = no adhesions, 1 = no serosal tears during adhesiolysis, 2 = serosal tears during adhesiolysis, 3 = bowel perforation during adhesiolysis). Only the worst IPA in each rat was scored. Rats were killed after the peritoneum and bowels were excised for histopathology.

Results: Pneumoperitoneum resolved in approximately 5 days. There were no associated side effects. The Lp-CDI group had significantly lower IPASS than the Lp group (0.23 +/- 0.46 vs 1.07 +/- 1.18, P < .05), and the LpBA-CDI group had significantly lower IPASS than the LpBA group (1.50 +/- 0.61 vs 2.40 +/- 0.55, P < .05). Histopathology showed pneumoperitoneum had no effect on the peritoneum or bowels.

Conclusions: Our results suggest that CDI pneumoperitoneum appears to prevent IPA, especially between bowel-bowel IPA.