心脏双瓣置换术麻醉期间血流动力学变化

Hemodynamic changese during the procedure or double cardiac valve replacement.

采用Ｓｗａｎ－Ｇａｎｚ导管及热稀释原理测定心排血量方法，对４９例择期行二尖瓣及主动脉瓣双瓣置换术麻醉期间的血流动力学进行了测定。结果表明：麻醉前心脏指数（ＣＩ）、左心功指数（ＬＶＷＩ）属正常范围，但平均肺动脉压（ＭＰＡＰ）、肺毛细血管嵌压（ＰＣＷＰ）、肺总阻力指数（ＰＴＲＩ）、右心功指数（ＲＶＷＩ）明显异常。诱导后右心前负荷（ＲＡＰ）升高，右心后负荷（ＭＰＡＰ、ＰＣＷＰ）、平均动脉压（ＭＡＰ）、（ＣＩ及左、右心作功降低，显示有心功能可能受抑；气管插管及锯胸骨后血流动力学各项指标均不同程度地回升并超过诱导前，提示心血管功能仍保持对应激的反应能力；主动脉及腔静脉插管时ＣＩ、ＭＡＰ、ＭＰＡＰ、ＰＣＷＰ、ＬＶＷＩ及ＲＶＷＩ均显著降低，显然与此期间近心性、出血及搬动、挤压心脏、严重心律失常等干扰左、右心前后负荷的平衡有关；体外循环后，由于手术纠正了瓣膜病变所致的血流障碍，ＭＰＡＰ、ＰＣＰＰ、ＰＴＲＩ、及 ＲＶＷＩ显著持续下降，而反映肺血管阻力的ＰＶＲＩ无变化；心肺转流（ＣＰＢ）结束后ＭＡＰ、ＳＶＲＩ明显减低，心脏功能也受损，提示此期间应尽早应用心血管活性药并提高患者的血细胞比容。

The hemodynamics of 49 scheduled patients during anesthesia and opration for mitral and aortic valve replacement were studied with the insertion of SwanGanz catheter and by the method of thermodilution technics.Pre-anesthesia CI and LVWI were in the nor mal range with abnormal MPAP, PCWP, PTRI and RVWI.Increase of RAP and decrease in MPA,PCWP, MAP, CI, LVWI and RVWI were observed during induction of anesthesia. The hemodynamic parameters returned to or exceded the pre-anesthesia values after trachcal intubation and sternotomy. The CI, MAP, MPAP, PCWP, LVWI and RVWI decreased signifi- cantly after insertion of aorta and vena cava catheter. The reduction of MPAP, P(IWP,PTRI and RVWI post-cardiopulmonary bypass (CPB) were significant and persistent with no change of PVRI.The lower MAP,SVRI and deterioration of cardiac performance post-CPB indicate that the administeration of positive inotropir agents and restoration of hematocrit are nec essary as early as possible.