Increasing whole blood oxygen affinity during rapid exchange transfusion: a potential hazard

Whole blood cell separators are being used to achieve partial exchange transfusions in patients with hemoglobin S. The rate and extent of the alteration of whole blood oxygen affinity, incurred by this procedure, has been determined in a patient with Hb S/C disease. The implications in terms of oxygen delivery to the tissues are described for this patient and also for patients with the more severe disease associated with Hb S/S. It is concluded that whole blood cell separators should be used with an awareness of the possible detrimental effects of acute increases of whole blood oxygen affinity in these patients.