Blood flow and pressure propagation in the canine femoral artery

Abstract

A series of experiments has been performed on the femoral artery of 20 anesthetized dogs in order to test the predictions of a theoretical, hemodynamic model. Simultaneous measurements of intra-arterial pressure and differential pressure, external vessel diameter and volume blood flow were recorded on analog tape and subsequently subjected to Fourier series analysis. Recordings were taken during control conditions and during periods of unilateral vagal stimulation and topical drug application. From the Fourier analysis of the recorded variables, values of hydraulic fluid impedance and propagation characteristics were computed for comparison to the model. Experimental values of fluid impedance, resistance and inductance compared well with the predictions of the model within the limitation of experimental errors. The propagation characteristics of the model were tested on data from the literature. The latter were used to compute values of phase velocity and attenuation coefficient, which were found to be in good agreement with the theoretical predictions of the model. The apparent propagation constant, obtained from pressure and differential pressure data, were used to compute values of (true) phase velocity. These were also found to agree well with the theoretical model. The ability of linearized wave propagation models to predict blood flow and pressure propagation values in the canine femoral artery has several important implications.