Platelet Increments and Their Relationship to Acidification

Acidification of platelet‐rich plasma to a pH of approximately 6.5 by the use of additional ACD anticoagulant solution before preparation of platelet concentrates results in a greater increment of the one‐hour posttransfusion platelet count and better clinical hemostatic effects when compared with preparations whose pH values are reduced to approximately 6.7 to 6.8. The latter preparations show greater tendency to aggregate spontaneously and a larger response to ADP in vitro than those at a pH of 6.5. If maximum recovery of platelets from a single donor is the primary objective, platelet‐rich plasma should be acidified to pH 6.5 before preparation of platelet concentrates. 1969 AABB