Rheological Factors Influencing Oxygen Transfer in Heart and Brain
Among numbers of factors affecting the oxygen transport to tissue from capillaries, capillary rheology and its distribution are most important in regulating the oxygen transport so as to comply with the metabolic requirement of organs such as heart and brain. To date, a number of studies have been performed to examine the role of the capillary topology (geometry and distribution) in the oxygen supply to tissue, but rheological factors have not yet received much attention (Niimi et al, 1983). The purpose of this research is to clarify the significance of the rheological factors in regulation of the oxygen transport to tissue from capillaries. Especially, we will emphasize how variable capillary hematocrits possibly affect the transcapi 1 lary oxygen transport. After describing some direct observations related to microcirculatory heterogeneity, such as the preferential flow in capillaries of heart and brain, we will numerically investigate the transcapillary oxygen transport phenomena by generating the flow conditions based on a “two-fluid model”.
KeywordsOxygen Transfer Oxygen Transport Capillary Blood Flow Coronary Microcirculation Rheological Factor
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