Development of comuter controlled assisted circulation system

利用微机研制了体外循环用泵控制系统。计算机监测的参数有中心静脉压、主动脉压、储血槽内的血容量、静脉拔管中一个小塑料袋的塌陷情况。在整个体外循环过程中，动脉输注和静脉回撤线的泵都是通过接口单元自动控制的。该系统通过比例积分控制算法调节中心静脉压力，以保持血管内容积恒定。设计了一种筛选算法来去除引入压力测量的伪影。在脱机期，灌注师可以选择中心静脉压控制或储血容量控制。应用计算机泵灌注治疗100例儿童心内直视手术，灌注流量和中心静脉压控制满意，手术稳定。与常规人工控制泵灌注相比，平均主动脉压和中心静脉压、净液体平衡、总排尿、血液化学和尿液分析均无显著差异。该系统具有实用价值，有望提高泵灌注的安全性。

A pump control system for a cardiopulmonary bypass is developed utilizing a microcomputer. The parameters monitored by the computer are central venous pressure, aortic pressure, blood volume in a reservoir, and collapsing of a small vinyl bag in a venous withdrawal tube. Both pumps in the arterial infusion and the venous withdrawal line are automatically controlled through an interface unit throughout cardiopulmonary bypass. The system regulates central venous pressure with a proportional-integral control algorithm to maintain intravascular volume constant. A screening algorithm is devised to remove artifacts introduced to the pressure measurement. At the weaning period, a perfusionist can select either the central venous pressure control, or a reservoir blood volume control. Computerized pump-purfusion was applied on 100 children cases during open heart surgery, where perfusion flow and central venous pressure were controlled satisfactorily with stable operation. Compared with conventional manually controlled pump-perfusion, no significant difference was noted in mean aortic pressure and central venous pressure, net fluid balance, total urination, blood chemistry, and urinalysis. This system is useful and is expected to improve the safety of pump-perfusion.