与人体血液需求量自适应的血泵流量控制算法

Algorithm for Controlling Blood Pump Flow Rate Adaptively with Requirement of Human Body

目的 为了使血泵驱动器能够根据患者的生理需求调节血泵输出,提出基于心率的自适应血泵控制算法,该算法得出的算法流量能随着生理需求而变化.方法 基于心率与心输出量之间的关系,将血泵输出流量设计成为心率的函数,根据文献中提供的正常人体心率与心输出量的数据,利用最小二乘法求得算法中的常量系数.为验证算法的准确性,计算出根据算法所得到的血泵输出流量与正常人体自然心脏心输出量之间的最大误差和相关系数.结果 当心率为75次/min时,根据上述算法得到的流量能达到5.01L/min;在50～120次/min心率范围内,算法中流量会随着心率的提高而增大;算法流量与自然心脏心输出量的相对误差为1%,相关系数为0.997.结论 以上结果表明,该算法可以根据受试者的血液需求量自动调整血泵工作状态.

Objective In order to regulate the blood pump responsing to the demand of patient＇ s cardio output, we proposed an adaptive blood pump control algorithm based on heart rate, so that the blood flow derived from the algorithm varies with the physiological needs. Methods Based on the relationship between heart rate and cardiac output, the algorithm was designed as a function of the heart rate. According to the data of heart rate and cardiac output derived from literatures, the constant coefficients were obtained through the least squares algorithm. To verify the accuracy of the algorithm, we calculated the maximum error and the correlation coefficient between the pump flow and cardiac output. Results With the algorithm,, the blood pump flow rate was 5.01L/min when heart rate of 75 beats/min, and the blood pump flow rate gradually became larger with the increase of heart rate within heart rate range from 50 to 120 times / min. The relative error between blood pump flow rate obtained from algorithm and cardiac output was 1%. Conclusion These results suggest that the algorithm for controlling blood pump flow rate regulate the pump in response to the demand of patient＇s cardio output.