In Reply:-Gunter correctly points out that it is possible to freeze the plasma after separation from a donated unit of blood, and thereby have the plasma, in addition to the erythrocytes, available from the same donor, when necessary. The potential reduction of the number of donors to which the recipient is exposed is the rationale for the recommendation to use whole blood rather than the combination of packed cells and fresh frozen plasma to treat massive blood loss. 
Although it is possible to carry out Gunter's suggestion in a small blood center, it would be logistically more difficult to effect for nondirected allogeneic units in larger centers or when transportation is required. It is easier (and likely less prone to error) to store the unit as whole blood rather than as two separate entities, although this results in some decrease in concentration of coagulation factors V and VIII. Separated, frozen plasma and erythrocytes should be made available on request for donor-designated and autologous units.
Richard B. Weiskopf, M.D., Professor, Departments of Anesthesia and Physiology and Cardiovascular Research Institute, University of California, San Francisco, 521 Parnassus Avenue, C450, San Francisco, California 94143-0648.
(Accepted for publication August 21, 1996.)