侧支体外循环的集中参数模型

A Lumped Parameter Model of the Peripheral Extra-corporeal Circulation

我们运用流体网络理论 ,建立了三参数单元的侧支体外循环集中参数模型。以三种不同外部压力泵源作为循环动力 ,使用体重为 2 0 kg狗的生理数据 ,探讨在心脏停止跳动时 ,血液由右颈总静脉流出 ,经离心血泵、人工肺回到左股动脉这样一种循环方式下 ,狗的脑、心、肺供血情况。建模中考虑静脉管的可坍塌性以及心脏停止跳动时的瓣膜开闭情况。我们采用能很好解决刚性问题的 GEAR算法求解常微分方程组 ,从而保证了计算结果的收敛。该计算结果表明侧支体外循环能够给狗提供一定量的血液供应 ,为狗恢复自主心跳与呼吸提供条件 ,从理论上证明了侧支体外循环进行急救的可行性 。

A three-element model of lumped parameter in peripheral extra-corporeal circulation of an animal has been proposed and set up according to the fluid network theory. GEAR method, appropriate for the computation of the rigid problems, was used to solve the ordinary differential equations, so that a good convergence of the solution to the equations has been achieved. Physiological data of a 20kg dog, obtained from our animal experiments were used to calculate the pressure and flow rate of important organs. The results of the mathematical model and animal tests showed that the peripheral extra-corporeal circulation could supply enough blood to the important organs, e.g. hrt and brain, when the natural heart beating stopped. The results from both theoretical and experiments are critical to the cardiopulmonary cerebral resuscitation for the animals as well as for human beings.