[Methods influencing intraoperative heat balance in the sterile enclosure (author's transl)].

More and more operations are performed in a sterile enclosure ("Sterilboxe") with a high fresh air turnover to achieve an optimum aseptic standard. This study investigated the question whether the climate of the "Sterilboxe" has a depressing effect on the body temperature of anaesthetized patients. Furthermore various devices were tested for their value in compensating for heat losses. The temperature of 55 patients was recorded during major operations. We found evidence, that there was regularly a fall of core temperature during operations in the "Sterilboxe", somewhat different to the behaviour of temperature in conventional theatres. Three methods for the compensation of heat loss were compared each against other and against the control whilst continually recording the oesophageal temperature. In the control group the temperature fall was 0.44 degrees C/h, in the group in which respiratory gases were optimally warmed and humidified the decrease was only 0.11 degrees C/h. Warming up all perfused liquids in a water-bath heat-exchanger showed a fall of temperature of 0.2 degrees C/h; with a Fenwal heatexchanger temperature decreased by 0.27 degrees C/h.