Change in blood conductivity with flow rate
Tóm tắt
The change in the electrical conductivity of erythrocyte suspensions with flow rate is shown to be dependent on erythrocyte shape, volume concentration, the shear rate and the rate of change of shear rate with time. Rouleaux formation also affects the changes observed at low shear rates. It is shown that experimental observations are consistent with changes in erythrocyte orientation as the primary mechanism of the process. Other mechanisms that have been proposed, such as electrokinetic effects, oxidation-reduction processes at the electrodes and axial migration of erythrocytes, cannot account for the experimental observations. Changes in blood conductivity with flow rate rate are shown to have very limited use in bloodflow metering and to be inherently incapable of high accuracy in the measurement of timevarying flows.
Tài liệu tham khảo
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