Effect of Ultrafiltration and Carbon Dioxide on Antithrombin Activity of Fresh and Stored Human Plasma

Abstract

The author''s previous finding of a rise in antithrombin titer after 5-10 days of storage of plasma in direct relationship with its degree of decalcification was confirmed. Antithrombin titer of both fresh and stored plasma is redueed by ultrafiltration or treatment with CO2 and to a limited degree, by treatment with O2. Treatment with N2 and absorption with Ca3(PO4)2 are ineffective. Concns. of prothrombin and of the labile factor are not modified by any of these procedures, with the exception of O2 which inactivates variable amts. of the labile factor. Blood collected with citrate-dextrose soln. for transfusion shows a limited rise of antithrombin activity during storage, which can be reduced to almost normal values by ultrafiltration or passage of CO2. When this blood is transfused after a storage of more than 2 weeks, the antithrombin titer of plasma is slightly and temporarily raised. This effect may be of clinical significance only in patients receiving heparin or having a circulating anticoagulant. In these cases, preliminary ultrafiltration or treatment with CO2 of the blood or plasma to be transfused might be advisable.