Effect of transfusion on hemoglobin flow and oxygen delivery in patients with sickle cell anemia--in vitro evaluation.

A method is given for the in vitro evaluation of transfusion therapy of patients with sickle cell anemia. Changes in volumetric flow rate, hemoglobin flow rate, and oxygen delivery at three values of PO2 (25, 40, and 80 mmHg) induced by transfusion of two units of AA blood in three patients are evaluated. The viscosity-shear rate data are obtained in a precision cone and plate viscometer with controlled environment. This data is then used to calculate flow rates in model tubes of varying diameters (50-500 microns). The increase in oxygenated hemoglobin flow rates at low oxygen tensions after transfusion can be striking-sometimes greater than a factor of two. A preliminary evaluation of the potential effect of auto-transfusion or androgen therapy on these flow rates is also discussed.