Basic factors determining the hemorheological disorders in the microcirculation.

Hemorheological properties and disorders are very specific in the microcirculation since blood is actually not a fluid in the capillaries and in the adjacent arterioles and venules. This is because almost half of the blood volume constitutes the red and white blood cells whose size is commensurable with the microvessels lumen. Based on perennial investigations we concluded that the advancement of blood in capillaries is primarily dependent on the "structure" of the flowing blood that determines the resistance to blood advancement in the microvessels rather than on the well-known hydrodynamic relationships characteristic for the larger blood vessels. Basing on the perennial research of the hemorheological disorders in the microvessels we succeeded to specify the principal factors determining the blood flow resistance in the microcirculation. These factors are as follows: the erythrocyte enhanced aggregability > their deformability > the local hematocrit > the blood plasma viscosity. Solution of these theoretical problems is very important for the theory and practical medicine, since the blood rheological disorders in the microcirculation play a significant role in development and outcome of such essential diseases as the cerebral and cardiac infarcts, the diabetus mellitus, arterial hypertension, tumor grow, and many others.