大鼠门静脉部分结扎后血流动力学的动态变化

Dynamic changges of hemodynamics in partial portal-vein ligative rats

目的 :通过动态观察血流动力学的变化 ,探讨门静脉高压发生、发展和维持的全过程。方法 :采用有创和无创相结合的方法 ,对血流动力学指标在门静脉部分结扎 (PVL)后不同时点进行检测。结果 :PVL大鼠表现为心输出量增加 ,全身血管扩张 ,血管阻力降低 ,局部血流量增加 ,血容量增加 ,平均动脉压降低和门静脉压升高。PVL后 2 4h即出现全身血管扩张 ,此后一直保持扩张状态。术后 48h心脏在射血分数不变的情况下 ,每搏输出量增加 ,同时局部血流量增加 ,心输出量增加。术后 72h血流动力学变化趋于稳定。结论 :全身血管扩张是血流动力学改变发生的始发因素 ,血容量增加。

Objective:To study the complete process of portal hypertensive emersion,development and maintenance by dynamic view of the changes of hemodynamics.Methods:The changes of hemodynamics of post partial portal vein ligation(PVL) in different time were measured with combination of injurious and uninjurious methods.Results:The PVL rats was characterized by increased cardiac output,regional blood flow,blood volume and portal pressure, decreased vascular resistance, mean arterial pressure and dilated systemic vasculature. Dilatation of systemic vasculature appeared at 24 hour post operation and maintains this dilatational state thereafter. Increased stroke volume at 48 hour post operation in the condition of unchanged ejection fraction was reflected by increased blood volume and increased regional blood flow and cardiac output simultaneously. Hemodynamics maintained stable at 72 hour post operation.Conclusion:Systemic vessel dilatation is the primary cause of the changes of hemodynamics. Increase of blood volume,regional blood flow and cardiac output are the secondary.