Forced-air warming versus routine thermal care and core temperature measurement sites

Hypothermia occurs commonly during the perioperative period and is preventable with proper warming measures and body temperature monitoring. Using a prospective, randomized study design, we compared forced-air warming (Warm Touch, Mallinckrodt Medical, Inc, St Louis, MO) (n = 15) with routine thermal care (n = 14) during the intraoperative and early postoperative periods. The results show that compared with routine thermal care, forced-air warming resulted in higher core temperatures both intraoperatively and postoperatively. The incidence of shivering was lower and thermal comfort scores were higher in the warming group. A secondary focus in this study was to assess the correlation between body temperatures measured at the urinary bladder, oral cavity, rectum, and tympanic membrane. The results indicated that the sites most highly correlated with tympanic temperature (listed in order of most to least correlated) were the bladder, rectum, and oral cavity. Assuming tympanic temperature is most representative of "core" temperature, oral measurements were likely to underestimate core temperature, whereas bladder and rectal temperatures overestimated core temperature. The relationship between body temperatures measured at commonly used monitoring sites must be recognized by nurses to account for the tendency to overestimate or underestimate core temperature. This knowledge can be applied in the management of patients in the operating room or PACU and specifically in the evaluation of PACU patients before discharge.