Tanaka Y, Morimoto T, Watari H, Miyazaki M
Jpn J Physiol. 1976;26(4):345-53. doi: 10.2170/jjphysiol.26.345.
The relationship between the hematocrit value and the absolute value of impedance of whole blood was analyzed. The results indicated that the hematocrit value was linearly proportional to the logarithm of the impedance of whole blood over the range of hematocrit values of 10 to 60% with a correlation coefficient of 0.995. The circuit used for detection of the impedance of whole blood was described. It required no adjustments during measurements and had a wide linear range. The sources of error during continuous measurements were the rate of blood flow through the sensor cell, the temperature of the blood, and the concentrations of plasma proteins and ions. Accordingly, the flow and temperature of blood were kept constant during measurements. Changes in the concentrations of plasma proteins and ions within physiological ranges caused errors of +/- 2.0%. Typical results of continuous measurements were presented, showing that the hematocrit values obtained by this method agreed well with those obtained by the conventional methods from the packed cell volume. An advantage of this method over the conventional methods was that it could follow rapid and transient changes in the hematocrit.
分析了血细胞比容值与全血阻抗绝对值之间的关系。结果表明，在血细胞比容值为10%至60%的范围内，血细胞比容值与全血阻抗的对数呈线性比例关系，相关系数为0.995。描述了用于检测全血阻抗的电路。该电路在测量过程中无需调整，线性范围宽。连续测量期间的误差来源包括流经传感器池的血流速度、血液温度以及血浆蛋白和离子的浓度。因此，测量期间保持血液的流速和温度恒定。血浆蛋白和离子浓度在生理范围内的变化会导致±2.0%的误差。给出了连续测量的典型结果，表明通过该方法获得的血细胞比容值与通过传统方法从红细胞压积获得的值吻合良好。该方法相对于传统方法的一个优点是它可以跟踪血细胞比容的快速和瞬时变化。
