Safe intraabdominal pressure of carbon dioxide pneumoperitoneum during laparoscopic surgery

The deliberate induction of carbon dioxide pneumoperitoneum during laparoscopic surgery could be a possible source of cardiovascular collapse. The effects of elevated intraabdominal pressure (IAP) on systemic hemodynamics and splanchnic blood flow created by insufflation of carbon dioxide were examined in anesthetized dogs.

Stepwise increases in IAP of 8 (n = 7), 12 (n = 7), and 16 (n = 7) mm Hg were applied to determine the threshold pressure that had minimum influence on these hemodynamics. Hemodynamic parameters were measured at baseline and 1, 2, and 3 hours after the start of insufflation.

At an IAP of 16 mm Hg, cardiac output was decreased significantly by 1 hour after the start of insufflation and became progressively lower during the procedure. Systemic vascular resistance was elevated significantly in parallel with the change in cardiac output. Although hepatic arterial blood flow was not decreased significantly, portal venous and superior mesenteric arterial blood flows were diminished significantly at 16 mm Hg, resulting in a decrease in total hepatic blood flow. No significant changes were observed in these parameters at 8 or 12 mm Hg.

Based on these results, an IAP from 8 to 12 mm Hg is recommended for laparoscopic surgery, to avoid complications caused by hemodynamic derangements.