Increased transperitoneal bacterial translocation in laparoscopic surgery.

BACKGROUND: The indications for laparoscopic surgery have expanded to include diseases possibly associated with peritonitis such as appendicitis, perforated peptic ulcers, and diverticulitis. The safety of carbon dioxide (CO2) pneumoperitoneum in the presence of peritonitis has not been proved. Our previous investigations demonstrated increased bacteremia associated with CO2 insufflation. In effort to clarify the relative effects of intraabdominal pressure and type of gas, this study was designed to measure bacterial translocation with different gases at different pressures of pneumoperitoneum.
METHODS: For this study, 110 rats were given intraperitoneal bacterial innoculations with Escherichia coli and equally divided into five groups of 20 animals each. The study groups included a control group with no pneumoperitoneum administered (n = 30), insufflation at a commonly used pressure of 14 mmHg with helium (n = 20) and CO2 (n = 20), and low insufflation at 3 mmHg with helium (n = 20) and CO2 (n = 20) in an effort to minimize influences related to pressure. Blood cultures were checked at 15-min intervals for the first 45 min, then hourly thereafter for a total of 165 min after peritoneal inoculation with 2 x 10(7) E. coli.
RESULTS: There is increased risk of bacterial translocation in comparing groups that underwent pneumoperitoneum with those that did not in the rat peritonitis model. Furthermore, these findings are dependent on the presence or absence of gas, but not necessarily on the type of gas used for insufflation. In the low-pressure groups of both gases (helium and CO2), bacterial translocation was significantly increased, as compared with the control group. Low pressure also was associated with increased bacterial translocation, as compared with high pressure, but beyond 30 min of insufflation, no significant differences were apparent.
CONCLUSIONS: The risk of bacterial translocation in the E. coli rat peritonitis model is increased with insufflation using CO2 or helium, and this effect is more significant at lower pressures (3 mmHg) than at higher pressures (14 mmHg). However, no clinically applicable conclusions regarding the relative effects from type of gas or insufflation pressures could be confirmed.