硬膜外阻滞对血流动力学及肝血流的影响

今天看到一篇文献，觉得对临床有些情况可能会有借鉴意义，如果心功能储备很差，全麻诱导后会导致低血压、血流灌注降低的，是否能先来个硬膜外阻滞呢？会不会使得血流动力学比较平稳呢？

摘要译文

利多卡因胸腰椎硬膜外阻滞对异丙酚麻醉犬全身血流动力学和肝血流的影响

背景
全身麻醉抑制循环减少肝血流量（HBF）。

与吸入麻醉相比，全凭静脉麻醉（TIVA）的循环抑制作用较弱，而使用局麻药的硬膜外阻滞通过阻断交感神经和扩张血管增加血流量。

目的
我们研究了胸腰椎硬膜外联合TIVA麻醉对犬HBF的影响。

方法
6只比格犬在T13和L1之间放置硬膜外导管，并用丙泊酚和维库溴铵麻醉。每隔1-2周给予生理盐水（对照组）或2%利多卡因（0.2ml/kg，然后是0.2ml/kg/hr）。从硬膜外注射前（T0）到110分钟，每隔10分钟记录心率（HR）、心脏指数（CI）、平均动脉压（MAP）和全身血管阻力指数（SVRI）。使用吲哚青绿试验测量清醒状态下和硬膜外注射后90分钟的HBF。

结果
HR和CI在不同治疗组之间没有差异。利多卡因治疗后MAP和SVRI显著低于对照组，最低MAP值为T10时的65±11 mmHg。与T0相比，利多卡因治疗后，HBF在T30、T60和T90显著升高（P<0.05）；而对照组在任何时间点都没有明显变化。

结论
尽管该技术降低了MAP，但与对照组相比，HBF要么维持在麻醉前水平，要么增加，这可能是由于选择性阻断交感神经节引起的肝动脉血管扩张所致。

原文摘要

Effects of thoracolumbar epidural anesthesia with lidocaine on the systemic hemodynamics and hepatic blood flow in propofol anesthetized dogs

General anesthesia reduces hepatic blood flow (HBF) from circulatory depression. Total intravenous anesthesia (TIVA) is associated with decreased circulatory depression compared to inhalation anesthesia, and epidural anesthesia using local anesthetics increases blood flow by blocking the sympathetic nerves and expanding blood vessels. We investigated the effects of thoracolumbar epidural anesthesia with TIVA on HBF in dogs. Six Beagle dogs had epidural catheters placed between T13 and L1 and were anesthetized with propofol and vecuronium. Physiological saline (control) or 2% lidocaine (0.2 ml/kg, followed by 0.2 ml/kg/hr) was administered at 1-2 weeks intervals. Heart rate (HR), cardiac index (CI), mean arterial pressure (MAP), and systemic vascular resistance index (SVRI) were recorded at 10-min intervals from before epidural injections (T0) to 110 min. Indocyanine green test was used to measure HBF during the awake state and until 90 min after epidural injections. HR and CI did not differ between treatments. MAP and SVRI after lidocaine were significantly lower than those of controls, and the lowest MAP value was 65 ± 11 mmHg at T10. Compared to T0, after lidocaine treatment, HBF was significantly higher at T30, T60 and T90 (P<0.05); while, after control treatment, no significant change was evident at any time point. Despite a decrease in MAP by this technique, HBF was either maintained at pre-anesthetic levels or increased in comparison to controls, probably due to vasodilation of the hepatic artery induced by the selective blockade sympathetic ganglia.

日积月累

epidural anesthesia硬膜外麻醉
intravenous anesthesia静脉麻醉
associated with与…有关; 参加; 与…相联系
inhalation anesthesia吸入麻醉
blood vessels血管; blood vessel的复数
cardiac index心脏指数；心指数；心脏输出指数
arterial pressure动脉压