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Deformation and haemolysis of red cells in shear flow

1974; Royal Society; Volume: 338; Issue: 1613 Linguagem: Inglês

10.1098/rspa.1974.0078

2053-9169

E. G. Richardson,

Erythrocyte Function and Pathophysiology

Many in vitro experiments are performed to investigate mechanical damage to red blood cells. A theoretical interpretation of such experiments involving high shear-rate flows is presented here. Since haemolysis affects individual cells attention is concentrated on a single cell. The model chosen for analysis is an ellipsoid in a uniform shear flow. The small size of the cell ensures a small particle-based Reynolds number and hence the applicability of existing solutions for slow flow past an ellipsoid. Assuming a flexible elastic membrane the resulting stresses and displacements are calculated for low shear-rates. Passing to higher shear-rates the behaviour of Rand’s viscoelastic membrane breakdown model when subjected to the calculated stresses is investigated. The non-uniform rate of cell rotation produces a prediction of steady growth of strain, without increase of applied stress, until haemolysis occurs. When cell shapes predicted for low shear-rates are compared with observations there is adequate agreement and a qualitative explanation of other observed phenomena may be given. The predicted times to haemolysis are evaluated for various shear-rates and compared with published experimental results giving order of magnitude agreement.