Using a Vortex To Disaggregate Platelet Clumps

Abstract

Clumping of platelets in blood anticoagulated with EDTA is a main cause of reports of falsely low platelet counts by automated analyzers. To obtain reliable platelet counts in such cases, laboratorians often collect and analyze a citrated or nonanticoagulated blood specimen. The patient thus is subjected to a second venous or capillary puncture, and the availability of results is delayed. Our data on an alternative approach suggest that reliable automated platelet counts can be obtained from many blood specimens that reveal microscopic platelet clumps after mixing them by vortex and rerunning the samples through the analyzer. Mixing the blood by vortex at the maximum possible speed for 1 to 2 minutes disaggregated platelet clumps completely in 44% of specimens and partially in another 49% of specimens.