Changes of Core Temperature on Tourniquet Duration

Background: Core temperature changes during tourniquet inflation and deflation have been reported. The aim of this study is to investigate the extent of core temperature changes during inflation and deflation, depending on tourniquet time. Methods: Esophageal temperature in sixty patients who undergoing knee arthroscopy with tourniquet longer than 1 h (group L, n = 30) and less than 1 h (group S, n = 30) were measured before inflation, 30 and 60 min after inflation, just before deflation, and 1 min interval for 10 min after deflation. Results: Tourniquet time in L and S group was 109 ± 20 min and 46 ± 10.7 min, respectively. Compared to baseline value of 35.7 ± 0.07℃, significant increase of 0.14 ± 0.02℃, 0.25 ± 0.03℃, 0.4 ± 0.05℃ were observed at 30, 60 min after inflation, and just before deflation, respectively in group L, and the increase of 0.11 ± 0.03℃ and 0.18 ± 0.03℃ at 30 min after inflation and just before deflation, respectively in group S. Temperatures from 2 to 10 min after deflation were significantly lower than value of just before deflation in each group (P＜0.05). At 10 min after deflation, 0.76 ± 0.13℃ in group L and 0.4 ± 0.04℃ in group S were lower than values of just before deflation in each group (P＜0.05). Temperature at 10 min after deflation was significantly different between the groups (P＜0.05). Conclusions: Extent of core temperature decrease after tourniquet deflation was dependent on the duration of tourniquet application. (Korean J Anesthesiol 2007; 53: 453~7)