Intestinal perfusion during pneumoperitoneum with carbon dioxide, nitrogen, and nitric oxide during laparoscopic surgery.

OBJECTIVE: To find out what effect insufflation pressure and type of gas have on intestinal perfusion during pneumoperitoneum. DESIGN: Randomized, controlled, prospective, experimental study. SETTING: University affiliated animal experimental laboratory, Sweden. ANIMALS: Fasted, anaesthetised, domestic pigs of both sexes operated on laparoscopically (n = 7, weight 26-31 kg). INTERVENTIONS: Insufflation of carbon dioxide (CO2), nitric oxide (NO), or nitrogen (N2) at intra-abdominal pressures of 0, 5, 10, 15 and 20 mm Hg. MAIN OUTCOME MEASURES: Cardiac output, portal blood flow, and jejunal mucosal perfusion. RESULTS: Cardiac output decreased during N2 and NO (15, 20 mm Hg) but not during CO2 insufflation because of an accompanying tachycardia. Portal flow decreased during insufflation with N2 and NO (15, 20 mm Hg) and CO2 (20 mm Hg). Jejunal perfusion was reduced during N2 and NO insufflation (5-20 mm Hg) but remained unchanged during CO2 insufflation (5-20 mm Hg). CONCLUSIONS: Insufflation with CO2 maintained jejunal mucosal perfusion, probably as a result of hypercarbia as N2 at equal pressures reduced mesenteric flow. The vasodilator NO provided no haemodynamic benefit.