Welham K C, Mohapatra S N, Hill D W, Stevenson L
Intensive Care Med. 1978 Jan;4(1):43-50. doi: 10.1007/BF01683136.
The suitability of the peak value of the first derivative of the thoracic electrical impedance dZ/dtmax has been investigated in dogs as a non-invasive index of changes in myocardial contracility by comparing if with the peak left ventricular dP/dt and the peak values of aortic blood velocity and acceleration. An increase in the inspired halothane concentration was used to produce changes in contracility. In 5 dogs the combined values for the correlation coefficient between dZ/dtmax peak velocity and acceleration were respectively 0.937, 0.954 and 0.950. In 14 out 15 comparisons p less than 0.001 and in one, p less than 0.01. On these grounds, dZ/dt max is proposed as a variable worthy of sconsideration in patient monitoring.
通过将胸电阻抗一阶导数的峰值dZ/dtmax与左心室dp/dt峰值以及主动脉血流速度和加速度的峰值进行比较，研究了其作为犬心肌收缩力变化的无创指标的适用性。吸入氟烷浓度的增加用于产生收缩力的变化。在5只犬中，dZ/dtmax峰值速度与加速度之间的相关系数合并值分别为0.937、0.954和0.950。在15次比较中的14次，p<0.001，1次p<0.01。基于这些理由，dZ/dt max被提议作为患者监测中一个值得考虑的变量。
