HEMODYNAMIC AND METABOLIC EFFECTS OF CO2 PNEUMOPERITONEUM IN AN EXPERIMENTAL-MODEL OF HEMORRHAGIC-SHOCK DUE TO RETROPERITONEAL HEMATOMA

Background: Diagnostic laparoscopy has been used in abdominal trauma p atients, although its role is not well defined. The safety of laparosc opic evaluation in trauma patients with severe intraabdominal hemorrha ge has not yet been analyzed. The purpose of this study is to evaluate the hemodynamic and metabolic effects of CO2, pneumoperitoneum (COI) in hemorrhaged animals through a retroperitoneal hematoma (RH). Method s: Twenty-two 15-20-kg mongrel dogs were monitored for systemic and pu lmonary hemodynamics, inferior vena cava pressure, and arterial blood gases. After 1 h of baseline, all animals were submitted to a RH. Afte r 45 min the dogs were randomized into two groups. Control (CTR): dogs were submitted only to a RH; pneumoperitoneum (PN): dogs were submitt ed to a RH and 45 min later they were insufflated to an intraabdominal pressure of 10 mmHg with medical-grade CO2, gas for 30 min. Echocardi ography was performed, only in PN animals, at baseline, 45 and 60 min after RH. Results: RH induced a shock condition with low, sustained le vels of arterial pressure, cardiac index, left ventricular stroke inde x, base excess, and oxygen delivery which were further depressed follo wing COI. Three deaths occurred in the PN group, all of them toward th e end of COI. During COI, hypercapnia was observed in one animal. COI did not impair systolic function or ejection fraction. Conclusions: CO I with an IAP of 10 mmHg may be deleterious in animals with hemorrhagi c shock due to an intraabdominal lesion. These findings could be clini cally significant in abdominal trauma patients.