一、引言心输出量是人体重要的心血管指标之一,阻抗法测心输出量因其具有无创性、使用简便和基本可靠等优点,引起了研究心血管工作者的注意。所用的仪器性能虽有不同,但原理基本一致。即在人体上加一高频电流,然后检测出测量段因血管容积波动造成的阻抗变化,据此算出心脏每搏排血量。 I. INTRODUCTION Cardiac output is one of the most important cardiovascular indicators in human body. Impedance cardiac output has attracted the attention of cardiovascular workers due to its advantages of noninvasiveness, ease of use and reliability. Although the performance of the instruments used are different, but the principle is basically the same. That is, in the human body plus a high-frequency current, and then detect the measurement section due to fluctuations in the volume of blood vessels caused by impedance changes, thus calculating the stroke volume of heart stroke.