Does pneumoperitoneum during laparoscopy increase bacterial translocation?

Background: To evaluate the impact of laparoscopy in the presence of peritonitis, this study was designed to assess bacteremia caused by E. coli-induced peritonitis with a carbon dioxide pneumoperitoneum in a rat model. Methods: Sixty Sprague-Dawley rats were divided into inoculum groups (no E. coli, 10⁶ colony-forming units [CFU] E. coli, and 10⁸ CFU E. coli), followed by induction of a carbon dioxide pneumoperitoneum or no pneumoperitoneum. Fifteen-minute-interval blood cultures were obtained to determine time of bacteremia development. Statistical assessment to determine significant differences among groups was done using ANOVA and t-test analysis. Results: A total of 20 animals with E. coli introduced into the peritoneum and a carbon-dioxide-induced pneumoperitoneum had more frequent positive blood cultures at all time intervals compared to identical inoculum subgroups without a pneumoperitoneum. ANOVA revealed a significant difference in bacteremia within the same concentration inoculum groups in animals receiving a pneumoperitoneum vs none (p < 0.01). Bacteremia increased significantly as inoculum concentrations increased (25% with 10⁶ E. coli inoculum vs 80% with 10⁸ E. coli), especially among the insufflated subgroups (45% with 10⁶ E. coli vs 100% with 10⁸ E. coli) over 180 min (p < 0.01). Conclusion: Carbon dioxide pneumoperitoneum increases the incidence of E. coli bacterial translocation from the peritoneum into the bloodstream in this rat model.