Shibata K, Yamamoto Y, Kobayashi T, Murakami S
Department of Anesthesiology, School of Medicine, Kanazawa University, Japan.
Anesthesiology. 1991 Feb;74(2):303-8. doi: 10.1097/00000542-199102000-00017.
The question as to whether reduction of plasma catecholamine concentration contributes to the beneficial effects of upper thoracic epidural anesthesia on survival during hemorrhagic shock was examined. Twenty-six dogs were anesthetized with halothane and nitrous oxide, and blood was withdrawn to reduce the mean arterial blood pressure (MAP) to 40 mmHg. The 12 dogs in group A received both upper thoracic epidural anesthesia before the hemorrhage and intravenous infusion of epinephrine (450 ng.kg-1.min-1) and norepinephrine (150 ng.kg-1.min-1) during hemorrhage. The 14 dogs in group B received none of these. At 20 min after the start of the bleeding, plasma catecholamine concentrations were increased in both groups more than ten-fold. There were no significant intergroup differences with respect to these concentrations at any point during the experimental period. During the 100-min period of hemorrhage, 1 of the 12 animals in group A and 10 of the 14 in group B died. A significant difference in survival was seen between the two groups over the 100-min hypotensive period (P less than 0.01 by the generalized Wilcoxon test). These results suggest that the survival benefit of upper thoracic epidural anesthesia cannot be explained simply by differences in the level of catecholamines in the plasma, and that perhaps differences in the level of catecholamines at the nerve endings or other factors may be more important.
研究了血浆儿茶酚胺浓度降低是否有助于上胸段硬膜外麻醉对失血性休克患者生存的有益作用。26只狗用氟烷和氧化亚氮麻醉，抽血使平均动脉血压（MAP）降至40mmHg。A组12只狗在出血前接受上胸段硬膜外麻醉，并在出血期间静脉输注肾上腺素（450 ng·kg-1·min-1）和去甲肾上腺素（150 ng·kg-1·min-1）。B组14只狗未接受上述任何处理。出血开始后20分钟，两组血浆儿茶酚胺浓度均增加了十倍以上。在实验期间的任何时间点，两组之间这些浓度均无显著差异。在100分钟的出血期内，A组12只动物中有1只死亡，B组14只中有10只死亡。在100分钟的低血压期，两组之间的生存率存在显著差异（广义Wilcoxon检验，P<0.01）。这些结果表明，上胸段硬膜外麻醉的生存益处不能简单地用血浆中儿茶酚胺水平的差异来解释，也许神经末梢儿茶酚胺水平的差异或其他因素可能更重要。
