Intravascular hemolysis secondary to ABO incompatible platelet products. An underrecognized transfusion reaction.

Transfusion of ABO-incompatible platelets to a cardiac surgery patients resulted in acute intravascular hemolysis complicated by ventricular tachycardia. Nine similar cases with significant morbidity or mortality have been reported in similar settings. Five fatalities caused by transfusion of ABO-incompatible platelet products have been reported to the US Food and Drug Administration during the last 4 years. Non-group O patients, particularly those with small plasma volumes, receiving multiple non-group specific platelets in a short time are at risk for intravascular hemolysis caused by passively infused anti-A1 or anti-B. To prevent intravascular hemolysis in such at-risk patients, the indications for platelet transfusion must be continually assessed. If transfusion of ABO-incompatible platelet products is necessary, consideration should be given to minimizing the accompanying plasma via further concentration of the platelets or by saline washing of platelet products.