Viscosity of normal human blood under normothermic and hypothermic conditions

Abstract

Although blood viscosity varies in relation to shear rate, hematocrit, and temperature, equipment is now available with which it may be measured in respect to each of these variables. A simple, clinically practical technique for such measurement is presented. Blood from 60 normal subjects was adjusted to hematocrits 0, 20, 40, 60, and 80, and the viscosity-shear rate relationships measured at 37.0, 32.0, 27.0, and 22.0 C. The data obtained are presented as a reference for future studies using this method. Technical details are discussed and some deserving areas of application are considered. shear rate; cone-plate viscometer; hematocrit-viscosity relationships; blood, plasma; hematocrit; temperature; blood flow impedance; perfusion; shock; oliguria; dyspnea; coma; heart surgery; blood rheology; metabolism Submitted on May 31, 1963