Development of a noninvasive method for determining blood viscosity

The aim of the study is to develop a new method for noninvasive determination of dynamic viscosity. In the developed method, the methods of mathematical modelling and the laws of rheology, mechanics, biomechanics and human physiology were used. It has been shown that an increase in blood viscosity leads to functional failure of various organs and tissues, disorders of the coronary and cerebral circulation. As a result of the analysis, it was revealed that blood can be considered as a colloidal suspension in which particles of erythrocytes and platelets are suspended, and the viscosity of such a colloidal system in microcirculation does not obey the Newtonian law. At the same time, the main factors that significantly affect blood viscosity include: blood pressure of hematocrit, platelet count, absolute amount of fibrinogen proteins and microglobulins, and lipoprotein concentration. A mathematical model has been obtained for determining the viscosity of the colloidal dispersed blood system, considering the concentration of the dispersed phase (blood cells) and the structure formation of blood; a model for determining the thickness of the boundary layer of blood corpuscles adsorbed on the inner surface of blood vessels is proposed and the mechanism of blood structure formation associated with the surface charges of erythrocytes and platelets is shown.