Transfusion of Blood Components

Abstract

Single units of whole blood may be conveniently, economically, and efficiently processed to supply individual preparations of red blood cells platelets and plasma. Although whole blood may be required for acute hemorrhage, concentrated red blood cells may be administered for other anemias. This fractiona-tion salvages 250-300 ml of platelet containing plasma per unit of whole blood for the preparation of platelet or plasma transfusions. In certain circumstances, transfused "packed" cells may, in fact, be more desirable than that of whole blood for optimal management of the primary disease. Platelets may be infused to thrombocytopenic patients in platelet-rich plasma or in platelet concentrates. In the absence of bleeding or sepsis administration of 1 x 1011 platelets will raise the circulating platelet count by an increment of 12, 500 cells/cu. mm in a recipient of one square meter one hour after transfusion. Platelet-poor plasma can be frozen, lyophilized or cryoprecipitated and in these forms it can supply labile clotting factors. Granulocytes, obtained from chronic myelogenous leukemic donors, have been transfused into leukopenic subjects and have been associated with beneficial changes in their clinical courses. Several instances of homologous myeloid grafts have been reported following the administration of these cells. Albumin infusions are not associated with hepatitis, and they may be used for volume expansion although the beneficial effects depend upon the availability of extravascular fluid. Hypoalbuminemia associated with a rapid turnover of intravascular protein responds poorly even to massive albumin transfusions. The decision to employ fibrinogen preparations should take into consideration the frequency of hepatitis associated with these transfusions. Hypofibrinogenemia secondary to defibrination or fibrinolysis may be exacerbated by the administration of fibrinogen and may respond to heparin or epsilon-aminocaproic acid.