Red Cell Aggregation and Red Cell Deformation: Their Influence on Blood Rheology in Health and Disease

Abstract

After decades of empirical description of both the bulk viscosity of blood and the microscopic appearance of intravascular blood flow, the work of GOLDSMITH and MASON (1,2), CHIEN (3) and associates, as well as that of MERRILL and WELLS (4) and WELLS and SCHMID-SCHONBEIN (5), has recently focused on a more detailed analysis of the underlying factors responsible for the rheological behavior of blood. The study of the microrheology was introduced by GOLDSMITH and MASON (1,2) as an approach for the understanding of the macrorheology of fluids, but it has more than heuristic value in the field of hemorheology. The microrheology of blood governs flow in the vast majority of the conduits in the mammalian circulation (6,7), since these most important channels of the circulation, are of the same dimension as the red cells and red cell ggregates. Knowledge of the microrheo1ogy of blood therefore is of paramount practical importance. This report is based on some of the studies and theories about the mechanisms that allow blood to flow and is concerned with variables that interfere with the fluidity of blood under pathological conditions.