Maintenance of body temperature by heated humidification.

Though difficult to prove conclusively, humidification of anesthetic gases during prolonged surgery appears beneficial. Even slight falls in body temperature are detrimental, causing significant increases in O2 consumption in the immediate postoperative period. A new heated humidifier which supplies gases at 100% relative humidity at 35 degrees C at the patient inlet has been used both to supply humidity and to prevent a fall in interoperative temperature. This was successfully employed in 19/25 prolonged procedures. The warmed humidified gases contributed significantly to the maintenance of homeostasis during anesthesia.