Does peritoneal mobilization increase laparoscopic acidosis?

Abstract

PURPOSE: It was hypothesized that laparoscopic colon surgery may be associated with increased absorption of CO₂ resulting from mobilization of lateral peritoneal reflections. METHODS: Six pigs underwent laparotomy with removal of a measured quadrant of peritoneum before insufflation to 15 mmHg with CO₂. Six paired control animals also underwent insufflation with CO₂ to 15 mmHg. Measurements of the end-tidal CO₂ (PetCO₂), arterial blood gas analysis for CO₂(PaCO₂), and pH were performed before insufflation, at 5 and 10 minutes following insufflation, then at successive 15-minute intervals for a total of two hours, and 15 minutes following desufflation. No attempt was made to correct the hypercarbia by increasing minute ventilation. RESULTS: PaCO₂ reached its maximum level at two hours with values of 70.77±5.54 mmHg and 64.62±5.18 mmHg in the peritonectomized and control groups, respectively. PetCO₂ also peaked at two hours to 60±13 mmHg for the study group and 54±11 mmHg for controls. pH reached its nadir at two hours, falling from a baseline of 7.45±0.08 to 7.23±0.09 in the study group, and from 7.42±0.04 to 7.24 ±0.04 in the control group. There were no statistically significant differences between the two groups for any of the parameters measured at each time interval. CONCLUSIONS: The hypothesis that peritonectomy produces greater CO₂ absorption during CO₂ pneumoperitoneum was disproved under these experimental conditions.