[Erythrocyte viscosity-deformability-aggregation. A clinical reality]

Current clinical practice and indications for drug therapy for vascular pathologies of different etiology reveal the need to measure blood viscosity, either on the spot or at the site of greatest impact. The Authors propose as easily performed method of calculation using Reid's well-known technique, which, based on the measurement of hematic filterability using filters with different sized pores, gives the viscosity of the various fractions which make up overall viscosity but which have a different impact on areas of the circulation and their functions: total blood viscosity, corpuscolar viscosity, plasma-erythrocytic viscosity. These are quantified in cP as a values which is independent of the degree of sanguification and are markers of a functional flow datum. Erythrocytic deformability, expressed as a percentage of the inverse viscous impact of red cells on total blood viscosity, is restricted to a narrow range in the control population, and is therefore a very reliable parameter for the assessment of pathological and pharmacological changes. In addition to normal values, changes in subjects suffering from thalassemia are used as a paradigmatic example of structural and morphological erythrocytic changes without other associated diseases. A model table illustrates the methods of calculation used to obtain the degree of filtration in cP from filtration data.