The Effect of Agitation of Stored Human Blood on Microaggregate Formation

Abstract

Microaggregates (MA) composed of platelets and white blood cells form during the storage of human blood. These particles are believed to be a cause of pulmonary insufficiency in patients receiving massive blood transfusions. The present controlled study determined the effect of constant gentle agitation of CPD[citrate-phosphate-dextrose]-anticoagulated blood, during storage at 4.degree. C, on the formation of MA. Using a Model T Coulter Counter, it was found that agitated blood contained significantly lower volumes of MA at 7 and 14 days than did nonagitated controls. Significant elevations, above control levels, of plasma free hemoglobin, lactic dehydrogenase, and potassium indicated significant injury to cellular components of agitated blood. This study raises serious doubts concerning the potential clinical usefulness of blood agitation during storage to prevent MA formation.