IT IS KNOWN that changes in body temperature occur during surgical operations with the patient under general anesthesia. Early investigations1-3 demonstrated that the body temperature frequently fell by 0.5 to 1.5 C; reasons suggested for this finding were loss of body heat by radiation in cold operating rooms,1,4 decrease in cellular oxidation,5 cutaneous vasodilation, and decreased muscular activity.6 It soon became apparent that hyperpyrexia could also occur during operations and in the immediate postoperative period.7 Moschcowitz in 19168 and Cutting in 1931,9 in a review of the literature, attributed hyperpyrexia during anesthesia to high ambient temperature and humidity frequently observed in operating rooms before the advent of air-conditioning. However, in the study by Clark and Orkin in 195410 patients showed a rise in body temperature at all ambient temperatures including those as low as 14.5 to 18 C (58 to 64 F).
GOLDBERG MJ, ROE CF. Temperature Changes During Anesthesia and Operations. Arch Surg. 1966;93(2):365-369. doi:10.1001/archsurg.1966.01330020157027