Association Between Temperature Management Using Passive Thermal Insulation and a Modified Aldrete Score During Cryoablation of Paroxysmal Atrial Fibrillation Under General Anesthesia

ABSTRACT Background Unintentional intraoperative hypothermia (core temperature < 36°C), a common and frequently preventable complication in patients undergoing surgery under general anesthesia (GA), involves adverse effects on coagulation and prolonged recovery from GA. Thus, this study aimed to clarify the effect of passive thermal insulation (PTI) with a heat insulation blanket (HIB) on successful early recovery from GA in patients undergoing cryoablation for atrial fibrillation (AF) under GA. Methods Fifty‐five patients undergoing cryoablation under GA for nonvalvular paroxysmal AF were prospectively assigned to the Blanket ( n = 28) or Control (conventional towelettes; n = 27) group. The esophageal temperature was measured using an esophageal temperature probe before and after cryoablation. The esophageal hypothermia was defined as a temperature < 36°C. The Δ in esophageal temperature was defined as the difference between the pre‐ and post‐anesthesia temperature. The primary endpoint of this study was successful early recovery from GA, defined as a Modified Aldrete score (MAS) ≥ 9 at 2 h after the discontinuation of sedation/anesthesia in patients undergoing cryoablation under GA. Results This study demonstrated that the PTI using HIBs significantly reduced the incidence of esophageal hypothermia from 93% to 68% and increased the rate of successful early recovery from GA from 37% to 64%. Conclusions PTI using HIBs was associated with a smaller decline in esophageal temperature and a higher proportion of patients achieving MAS ≥ 9 at 2 h after discontinuation of anesthesia during cryoablation under GA. Larger studies using validated core temperature measurements and clinically meaningful recovery endpoints are warranted. Trial Registration This study was registered in the University Hospital Medical Information Network Clinical Trial Registry of Japan (UMIN000057904)