Voltage clamp method for the use of electrical admittance plethysmography in human body segments
Voltage clamp method for the use of electrical admittance plethysmography in human body segments
复制标题
电压钳法在人体节段中使用电导纳体积描记法
DOI：
10.1007/bf02510798
复制
发表时间：
1995
影响因子：
3.2
通讯作者：
M. Nakagawara
中科院分区：
文献类型：
--
作者：
K. Yamakoshi;M. Nakagawara
电阻抗（NYBOER，1970; KUBICEK等人，1970）或导纳体积描记法（ITO等人，1976年; YAMAKOSHI等人，1978）仍然可以是用于无创测量血容量变化和/或血流的最简单和最方便的方法之一，仅需要将电极附接在所涉及的身体节段上。因此，已经有许多关于心输出量（CO）（或每搏输出量，SV）和局部血流量（LBF）的无创测量的研究，结合静脉闭塞技术，特别是使用阻抗法（GEDOES和BAKER，1989）。相比之下，我们以前使用的adamittance体积描记技术，它承担的阻抗的反比关系。该方法在简单性和实用性方面比阻抗法有更大的改进，因为要测量的变量仅是用于SV确定的导纳脉动（dY/dt）的一阶导数（ITo等人，1976; BUKHA等人，1981）和仅在静脉闭塞后的导纳变化（6 Y）用于LBF测量（YAMAKOSm等，1978; 1979; t980; SHIMAZU等人，1982年）。然而，用电路获得生物阻抗信号的高精度测量比用相对容易的恒流技术获得的生物阻抗信号的测量困难得多，因为模拟IC分频器通常用于执行生物阻抗信号的倒数转换。BUKHAm等人，1981年）。因此，在这项工作中，我们提出了一种电压钳方法，以获得具有相当高的精度的生物导纳信号，但非常简单的电路，没有这样的模拟分压器。介绍了所设计装置的外形、主要电路及测量精度。并给出了在CO和LBF测量中的应用。
ELECTRICAL IMPEDANCE (NYBOER, 1970; KUBICEK et aL, 1970) or admittance plethysmography (ITO et al., 1976; YAMAKOSHI et aL, 1978) may still be one of the simplest and most convenient methods for the non-invasive measurement of blood volume change and/or blood flow, requiring only the attachment of electrodes on the body segment concerned. There have therefore been many studies on the non-invasive measurement of cardiac output (CO)(or stroke volume, SV) and regional blood flow (LBF), in conjunction with the venous occlusion technique, in human limbs particularly using the impedance method (GEDOES and BAKER, 1989). In contrast, we have previously used the adamittance plethysmography techifique, which bears an inverse relation to that of impedance. This method is more improved with respect to simplicity and practicability than the impedance method, as the variable to be measured is only the first derivative of admittance pulsations (dY/dt) for SV determination (ITo et aL, 1976; BUKHA~ et al., 1981) and only the admittauce change (6Y) following the venous occlusion for LBF measurement (YAMAKOSm et al., 1978; 1979; t980; SHIMAZU et al., 1982). However, the highly accurate measurement of the bio-admittanee signal has been much more difficult to obtain with electrical circuitry than the measurement of the bio-'mlpedance signal obtained by the relatively easy technique of the eomtant current~ areuit, because an analogue IC divider was conventionally used to perform the reciprocal conversion of the bio-impedanee signal CtTO et aL, 1976; YAMAKOSI-a et aL, 1979; BUKHAm et al., 1981). In this work, we therefore propose a voltage clamp method to obtain the bio-admittance signal with fairly high accuracy, but with very simple circuitry without such an analogue divider. The outline, main electric circuits and measurement accuracy of a device designed. by this method are presented, together with an application to CO and LBF measurements.