PLASMA AND WHOLE-BLOOD VISCOSITY

The physical aspects of viscosity [in humans] were reviewed. The measurement of plasma viscosity affords a useful non-specific index of disease which some believe to be superior to that provided by the ESR [erythrocyte sedimentation rate]. Studies of red cell flexibility and internal viscosity are directly relevant to any understanding of blood flow through small vessels. Such studies may throw more light on the behavior of sickle cells and other deformed or damaged erythrocytes in the micro-circulation. The interactions of red cell aggregation, low shear rate and fibrinogen or fibrinogen degradation product concentrations must be considered in any observation on the pathogenesis of venous thrombosis. The manufacture and marketing of drugs which purport to lower blood viscosity and increase red cell flexibility indicate that therapeutic manipulation of the physical properties of blood is becoming both a reality and an objective.