Evaluation of blood filters: dynamics of platelets and platelet aggregates.

Microaggregates of platelets have been found in stored blood and in extracorporeal circulation systems and the potential microembolism of these particles intensely studied. Four currently available filters were studied for their filtration effectiveness of induced platelet microaggregates and for the removal of normal platelets from blood collected in acid citrate dextrose or heparin. Dacron wool filtration significantly (P less than 0.001) reduced aggregates in 13 to 80 mu sizes to a level similar to that in normal blood. In general, as filtration effectiveness increased so did the elimination of normal platelets.