THE OPTIMUM PNEUMOPERITONEUM PRESSURE FOR LAPAROSCOPIC SURGERY IN THERAT MODEL - A DETAILED CARDIORESPIRATORY STUDY

Background: There is increasing interest in the rat model of laparosco pic surgery, This study evaluates the cardiorespiratory effects of inc reasing CO2 pneumoperitoneum (PP) in the rat. Methods: Nine Sprague-Da wley rats were subjected to CO2 PP at pressures of 2, 5, 10, and 15 mm Hg or control (no PP) under anesthesia. Catheters were placed in the f emoral artery and the jugular vein to measure heart rate (HR), blood p ressure (MAP), and arterial pH, PCO2, PO2, and HCO3. A thermistor prob e in the aortic arch measured cardiac output (CO) and blood temperatur e (BT). Results: CO2 PP had no effect on CO, MAP, or BT at any pressur e. CO2 PP greater than 5 mmHg caused significant bradycardia and CO2 P P greater than 10 mmHg caused significant respiratory acidosis. Conclu sions: CO2 PP pressures above 10 mmHg in rat should be avoided when pe rforming laparoscopic surgery in the rat model.