Carbon dioxide pneumoperitoneum prevents intraperitoneal adhesions after laparotomy in rats

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°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.