Comparison of immunologic and physiologic effects of CO2 pneumoperitoneum at room and body temperatures

Background: Prolonged and complex laparoscopic procedures expose patients to large volumes of cool insufflation gas. The aim of this study was to compare the effects of a conventional room temperature carbon dioxide (CO2) pneumoperitoneum with those of a body temperature pneumoperitoneum. Methods: Patients were randomized to undergo laparoscopic cholecystectomy with a CO2 pneumoperitoneum warmed to either body temperature (n = 15) or room temperature (n = 15). The physiologic and immunologic effects of warming the gas were examined by measuring peroperative core and intraperitoneal temperatures, peritoneal fluid cytokine concentrations, and postoperative pain. Results: The mean duration of surgery was 32 min in both groups. Core temperature was reduced in the room temperature group (mean, 0.42 degrees C; p < 0.05). No reduction in temperature occurred when the gas was warmed. Greater levels of cytokines were detected in peritoneal fluid from the room temperature insufflation group tumor necrosis factor alpha (TNF-alpha): mean, 10.9 pg/ml vs. 0.42, p < 0.05; interleukin 1 beta (IL-1 beta): mean, 44.8 pg/ml vs. 15.5, p < 0.05; and IL-6: mean, 60.4 ng/ml vs. 47.2. Then was no difference in postoperative pain scores or analgesia consumption between the two groups. Conclusions: The authors conclude that intraoperative cooling can be prevented by warming the insufflation gas, even in short laparoscopic procedures. In addition, warming the insufflation gas leads to a reduced postoperative intraperitoneal cytokine response.