Cardiac morphology and left ventricular function in normotensive morbidly obese patients with and without congestive heart failure, and effect of weight loss

BACKGROUND: Prevention of hypothermia during abdominal surgery by insulating or heat-transferring methods has been the subject of numerous investigations. This study approaches the problem from a less discussed point of view, i.e. the effect of different surgical techniques on body temperature changes. METHODS: Body temperature was measured at 3 core and 6 skin points in 40 patients scheduled for cholecystectomy through open laparotomy or laparoscopy with pneumoperitoneum created and maintained with unwarmed carbon dioxide (CO2) insufflation. End-tidal CO2 was kept constant by adjustments of respiratory frequency. Anaesthesia, intravenous infusions, and draping of the patients were standardized. RESULTS: During the first 1 h of anaesthesia core temperatures decreased approximately by 0.7 degrees C and distal skin temperatures increased by 7 degrees C in both groups. At the end of surgery heat balance was similar in both groups. An increase of 2.5 1.min-1 in respiratory minute volume was needed to control end-tidal CO2 levels in the laparoscopy group during pneumoperitoneum which was maintained with a CO2 flow of 1.2 1.min-1 through the abdominal cavity. CONCLUSION: Laparoscopic technique with unwarmed carbon dioxide insufflation does not offer any advantage in terms of body temperature changes when compared to open surgery.