Kasaba T, Tanaka N, Takasaki M
Department of Anesthesiology, Miyazaki Medical College.
Masui. 1998 Aug;47(8):939-43.
The choice of epidural anesthesia for patients with bronchial asthma is controversial. We studied the effect of epidural anesthesia on airway constriction induced by methacholine or capsaicin in cats. Cats were anesthetized with pentobarbital and mechanically ventilated. Peak airway pressure and compliance, as well as cardiac sympathetic and vagal nerve activity were recorded. We sprayed 0.2% methacholine of 0.2% capsaicin into the trachea to produce airway constriction, and 15 min after drug spray we injected 2% lidocaine 1.0 ml into the epidural space. Methacholine increased peak airway pressure by 25% and decreased compliance by 26%. Capsaicin increased peak airway pressure 20% and decreased compliance 22%. After epidural anesthesia, cardiac sympathetic nerve activity decreased to 40% and 44%, vagal nerve activity decreased to 92% and 61% of control values in methacholine and capsaicin groups, respectively. However, here were no changes in the peak airway pressure and compliance in the two groups. These results suggest that epidural anesthesia, even if epidural anesthesia decrease sympathetic nerve activity, has no effect on the airway constriction induced with methacholine or capsaicin.
支气管哮喘患者硬膜外麻醉的选择存在争议。我们研究了硬膜外麻醉对猫体内由乙酰甲胆碱或辣椒素诱发的气道收缩的影响。猫用戊巴比妥麻醉并进行机械通气。记录气道峰值压力和顺应性，以及心脏交感神经和迷走神经活动。我们将0.2%的乙酰甲胆碱或0.2%的辣椒素喷入气管以产生气道收缩，在喷药15分钟后，我们将2%利多卡因1.0毫升注入硬膜外腔。乙酰甲胆碱使气道峰值压力增加25%，顺应性降低26%。辣椒素使气道峰值压力增加20%，顺应性降低22%。硬膜外麻醉后，在乙酰甲胆碱和辣椒素组中，心脏交感神经活动分别降至对照值的40%和44%，迷走神经活动分别降至对照值的92%和61%。然而，两组的气道峰值压力和顺应性均无变化。这些结果表明，硬膜外麻醉即使降低了交感神经活动，对由乙酰甲胆碱或辣椒素诱发的气道收缩也没有影响。
