Platelet transfusion. Current techniques, remaining problems, and future prospects.

Abstract

The use of platelet transfusions to stop or to prevent bleeding in patients with thrombocytopenia or platelet dysfunction has accelerated in the past decade. Platelet counts and bleeding times, performed in conjunction with careful clinical evaluation of the patient, are appropriate guides in assessing the need for platelet transfusion. Complications of platelet transfusions are similar to those of red cell transfusions, with some additional concerns. Pooled random donor or single-donor apheresis concentrates, either randomly or selectively matched, are the major platelet products available. In most cases, transfusion requirements can be satisfied by use of random donor units. Proper evaluation of the effectiveness of transfused platelets is essential in determining the dose and frequency of future platelet transfusions. Refractoriness to random donor platelets eventually occurs in many recipients. This is most commonly associated with alloimmunization to histocompatibility antigens, but other platelet alloantigens may play a role. Many in vitro tests for platelet antibodies have been developed, and the clinical utility of these assays in selecting compatible platelets is now under evaluation. Strategies and different approaches to the management of thrombocytopenic patients with hypoplastic bone marrow states are also reviewed.