Abstract
Platelets were removed from 25 patients with leukemia during remission and were frozen for subsequent transfusion. With 5 per cent dimethyl sulfoxide as a cryoprotective agent, we froze 3 to 5 units of pooled platelet concentrate by simply placing the platelets in the vapor phase of a liquid nitrogen freezer. Ninety-one transfusions of platelets stored for 13 to 400 days were administered. The mean freeze-thaw loss was 13 per cent, and the corrected one-hour increment in platelet count was 13,700 per microliter, corresponding to a recovery of 53 per cent of the predicted value. In many patients most or all of the transfusion requirements were met with frozen platelets. Our results indicate that frozen platelets can circulate and function hemostatically. Autologous frozen platelets are of particular value in the management of alloimmunized patients and have become an integral part of our transfusion support program. (N Engl J Med 299:7–12, 1978)
INCREASED availability of platelets for transfusion has largely eliminated hemorrhage as a factor limiting aggressive chemotherapy for leukemia and other cancers. Despite immunosuppressive and cytotoxic therapy, however, the majority of patients with leukemia become alloimmunized and refractory to non-histocompatible platelets within four to six weeks after transfusions are begun,
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thereby potentially severely compromising maintenance and reinduction chemotherapy. Previous studies from this laboratory demonstrated the feasibility of platelet-pheresis of patients with leukemia in remission and freezing the platelets for transfusion during subsequent periods of thrombocytopenia, with a resulting decrease in the need to locate HLA-matched donors.
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Changes in technic have improved . . .