Abstract
In rigid tubes the electrical conductance of blood has been shown to vary with the blood velocity within certain limits. The change in conductance was independent of any increase in the blood volume but was related to the diameter of the tube and the velocity of the flow. The larger the diameter of the tube the greater was the percentage change in conductance at any specific velocity. The conductance changes depend on the velocity and the integral of the velocity, and so if the blood flow has a velocity pulse the conductance variations will also be phasic. The conductance changes in rigid tubes are the result of axial accumulation and orientation of the RBC's, as a function of velocity, although axial accumulation appears to be of much smaller magnitude than predicted theoretically.