EFFECT OF MOTION ON THE ELECTRICAL CONDUCTIVITY OF THE BLOOD

Abstract

The electrical resistance of defibrinated beef blood and dog''s blood varies with the velocity of flow when the blood is put in motion. The tendency for the resistance to increase at slow flows is an "electrode effect" depending on the interaction between some samples of blood and some types of electrodes. The decrease in resistance at faster flow''s is the true "flow effect." The change is primarily one of pure ohmic resistance, as shown by the fact that it occurs when either alternating or direct current is used for making the conductivity measurements. The exps. here reported show that the flow effect is peculiar to blood and is due to the presence of the formed red blood cells in the flowing stream, and that the property of the erythrocytes to stick together in clumps which are subsequently separated by the flow motion is responsible for the resistance changes.