The efficacy of warming blanket on reducing intraoperative hypothermia in patients undergoing transurethral resection of bladder tumor under general anesthesia

ABSTRACT

BACKGROUND: Perioperative hypothermia, defined as a core temperature under 36℃, increases the risk of cardiac complication, bleeding and infection. This study aimed to compare the hypothermia-preventing effects of a warming blanket (Ready-heat®) and one-layer cotton blanket in patients undergoing transurethral resection of the bladder (TURBT) under general anesthesia. METHODS: Patients undergoing TURBT under general anesthesia were allocated to the warming blanket (N = 23) or one-layer cotton blanket (N = 23) groups. Ten minutes before induction of anesthesia, warming blanket or one-layer cotton blanket was applied according to the assigned group. Tympanic temperature was measured just before induction of anesthesia. Esophageal temperature and tympanic temperature were measured from 20 min after induction of anesthesia at 10-min intervals. Tympanic temperature was measured at 10-min intervals over a 30-min period in the post-anesthesia care unit (PACU). In addition, the incidence and intensity of shivering and thermal comfort were also measured. RESULTS: The core temperature during general anesthesia showed no significant intergroup difference. The warming blanket group showed a lower incidence of hypothermia at 1 h after induction of anesthesia. Tympanic temperature, the incidence and intensity of shivering, and thermal comfort in the PACU showed no significant intergroup differences. CONCLUSIONS: Application of the warming blanket or one-layer cotton blanket for 10 min before induction of anesthesia showed no hypothermia-preventing effects. However, at one hour after induction of anesthesia, warming blanket application reduced the incidence of hypothermia to a greater degree than one-layer cotton blanket.