胶体扩容对异氟醚-硬膜外阻滞复合麻醉时肝血流的影响

Polygeline Decreases the Disturbence of systemic and Hepatic Hemodynamics caused by Epidural Block Combined with Isoflurane Inhalation

目的：探讨硬膜外阻滞复合异氟醚吸入全麻对血流动力学和肝血流的影响及其静脉输入３．５％尿素交连明胶（ＵＧ）的作用。方法：１８只犬分两组，行胸段硬膜外阻滞后吸入０．５和１．０ＭＡＣ异氟醚。实验组硬膜外阻滞前开始静脉输入ＵＧ１２ｍｌ／ｋｇ。监测体循环、肺循环、肝动脉、门静脉血流动力学。肝血流用电磁血流仪测定。结果：对照组硬膜外阻滞后ＢＰ、ＨＲ、肝动脉阻力和门静脉血流均下降，加吸０．５ＭＡＣ异氟醚使外周血管阻力（ＳＶＲ）、肺动脉压和门静脉压降低；１．０ＭＡＣ后心排血量下降、肝动脉血流也比０．５ＭＡＣ时减少。心搏量（ＳＶ）于吸入异氟醚后有所升高。实验组硬膜外阻滞后ＨＲ减慢、ＳＶ增加而ＳＶＲ下降，肝脏循环稳定。吸入异氟醚后全身和肝脏血流动力学变化显著轻于对照组。结论：硬膜外阻滞后，随异氟醚浓度升高，体循环、肺循环、肝动脉、门静脉血流动力学发生显著变化；胶体液扩容对此有明显的防治作用。

Objective: To explore whether colloid solution 3.5% polygeline (UG) could change the effects of epidural block combined with isoflurane inhalation on systemic, pulmonary and hepatic hernodynamics. Methods: 18 healthy mongrel dogs anesthetic with epidural block combined with 0. 5 or 1. 0 MAC isoflurane inhalation were divided into 2 groups randomly, control group(group I )and UG group (group Ⅱ ). In group Ⅱ, UG of 12ml/kg was infused introvenously. Systemic, pulmonary and hepatic hemodynamics were studied. Blood flow of hepatic artery and portal vein was monitored continuously with electromagnetic flowmeter. Results: In group I, HR, MAP, hepatic artery resistance and portal vein blood flow decreased significantly after epidural block. Combined with 0. 5MAC isoflurane, SVR, MPAP, PVP decreased and SV increased. With 1. 0 MAC, CO decreased and hepatic artery blood flow was lower than that in 0. 5 MAC. Ⅱ group Ⅱ, after epidural block HR and SVR decreased and SV increased significantly. There was no significant change of hepatic hemodynamics. During isoflurane inhalation, changes of systemic, pulmonary and hepatic hemodynamics were significantly less important than those in group I. Conclusion: Epidural block combined with high concentration of isoflurane inhalation causes disturbance of systemic, pulmonary and hepatic hemodynamics. The disturbance can be prevented effectively by UG infusion.