Does peritoneal mobilization increase laparoscopic acidosis?

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.