The effect of pneumoperitoneum on bacterial clearance and RES functions in a model of E. coli peritonitis

The use of laparoscopic surgery in peritonitis has increased rapidly. The present study examined the effects of pneumoperitoneum on bacterial clearance. Spraque-Dawley rats were divided into six groups of seven animals. In groups 1 and 4, laparotomy with a midline incision was performed and 10(9) E. coli in a volume of 1 ml inserted into the peritoneal cavity. Groups 2, 3, 5, 6 received an identical quantity of E. coli by intraperitoneal injection. Groups 3 and 6 received carbon dioxide pneumoperitoneum at a constant pressure of 5 mmHg for 60 minutes after intraperitoneal injection of E. coli. In one hour groups; the mean bacterial counts per lung from the E. coli injection with laparotomy group was significantly higher than for the E. coli injection with pneumoperitoneum group (p < 0.05). The mean bacterial counts per kidney in the E. coli injection with laparotomy group was higher compared with the E. coli injection and E. coli injection with pneumoperitoneum groups (p < 0.0001). There was statistically significant difference in quantitative bacteraemia between the E. coli injection with laparotomy group and the E. coli injection or E. coli injection with pneumoperitoneum groups (p < 0.05). In four-hour groups; the mean bacterial counts of lungs and liver-spleen were significantly higher in the E. coli injection with laparotomy group than in the E. coli injection and E. coli injection with pneumoperitoneum groups (p < 0.05 and p < 0.001 respectively). The quantitative bacteria was significantly higher in the E. coli injection with laparotomy group than in the E. coli injection and E. coli injection with pneumoperitoneum groups (p < 0.05). This study demonstrates that pneumoperitoneum impairs the clearance of bacteria from the peritoneal cavity in an experimental model of peritonitis. However, we could not detect the deleterious effects of pneumoperitoneum compared with laparotomy.