RHEOLOGY OF HUMAN BLOOD. STUDIES ON THE FLOW OF FRESH VENOUS BLOOD AND OF CITRATED BLOOD THROUGH TUBING OF DIAMETERS BETWEEN 0.09 AND 0.20 CM

Abstract

Numerous studies have demonstrated that the rheological properties of blood are anomalous , in particular , that rate of flow through cylindrical tubing is not related linearly to the imposed gradient in pressure and that the viscosity of blood increases at low rates of flow ( 1-10 ). sitate that any study of the rheological properties of blood must examine the dependence of viscos- ity upon applied shearing stress . Investigative work on blood is complicated by the finding that the very removal of blood from the vascular system is associated with changes plasma proteins-or they may be related to structural damage of the cells and other proc- vented and data obtained on blood almost in its native state by a procedure first described by Hurthle ( 15 ), in which capillary needles were introduced into the carotid arteries of a dog ; to examine the rheological properties of human with a method based on the Hfirthle principle . different pressure gradients were obtained during human subject through a needle and polyethyl-