토끼에서 엔푸루렌-에피네프린에 의한 부정맥에 흉추 경막외마취와 미주신경 절단의 효과

Background : To evaluate the effects of thoracic epidural anesthesia, with or without bilateral vagotomy, epinephrine-induced arrhythmias were studied in 31 rabbits anesthetized with 1 MAC enflurane. Methods : Logdose protocol was used for the infusion of epinephrine; its arrhythmic dose being defined as the smallest infusion rate produced four or more continuous or intermittent arrhythmias within 15 seconds. Results : The values (geometric mean) of arrhythmic doses and the plasma concentration of epinephrine during arrhythmia were as follows: 10.21 g·kg 1·min 1 and 83.16 ng/ml in epidural control group; 118.90 g·kg 1·min 1 and 677.76 ng/ml in epidural lidocaine group (P＜0.05); 6.34 g·kg-1·min 1 and 96.42 ng/ml in intravenous lidocaine group; 8.65 g·kg 1·min-1 and 44.64 ng/ml in vagotomized-epidural control group; and 12.03 g·kg 1·min 1 and 95.35 ng/ml in vagotomized- epidural lidocaine group. Conclusions : The data suggest that thoracic epidural anesthesia raises the threshold for enflurane- epinephrine arrhythmias in rabbits and that this effect is eliminated by bilateral vagotomy. (Korean J Anesthesiol 1997; 33: 617∼626)