Incidence of transfusion reactions and retention of procoagulant and anticoagulant factor activities in equine plasma.

Abstract

BACKGROUND: The extent of preservation of clotting factors and incidence of transfusion reactions to noncommercial equine plasma is not documented. HYPOTHESIS: Equine frozen plasma would retain its coagulation factor activity within the reference range and the incidence of transfusion reactions would be low. ANIMALS: Ten plasma donor horses. Fifty clinically ill hospitalized horses receiving plasma were reviewed to determine the incidence of reactions. METHODS: In vitro study and retrospective case review. Plasma was prepared by gravity sedimentation from whole blood refrigerated for 48 hours. The activities of factors VII through XII, antithrombin (AT), and Protein C were measured. Factor activities were compared for plasma samples obtained before blood collection (S0), after 48 hours of gravity sedimentation at 5 degrees C and after plasma separation (S1), and after 90 days of storage at -20 degrees C (S90). The medical records of 50 consecutive clinically ill horses receiving frozen plasma were reviewed to determine the incidence of transfusion reactions. RESULTS: The combined effect of plasma harvest, gravity sedimentation, decantation, and freezing caused significant reductions in factors IX, (43%P= .0013), X, (33%P= .0001), XI, (48%P= .0008), AT, (10%P= .02), and Protein C (26%P= .0001). Activities for all factors analyzed, except factor X, remained within the reference ranges. Transfusion reactions were recorded for 5/50 horses. CONCLUSIONS AND CLINICAL RELEVANCE: Clotting factors, AT, and Protein C were well preserved. The incidence of reactions to frozen plasma was 10%.