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Microfluidic Flow Chambers Using Reconstituted Blood to Model Hemostasis and Platelet Transfusion In Vitro
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Primary haemostasis and its assessment by laboratory tests

A J Reininger1

  • 1Abteilung für Transfusionsmedizin und Hämostaseologie, Klinik für Anästhesiologie, Klinikum der Universität München, Ziemssenstr. 1, 80336 München, Germany. Armin.Reininger@med.uni-muenchen.de

Hamostaseologie
|January 31, 2006
PubMed

Platelets constantly patrol the inner surface of blood vessels searching leaks to be sealed, in order to prevent blood loss. When they detect a vessel injury their action can be divided into three phases. ADHESION: The platelets adhere to the injured blood vessel wall via their receptors glycoprotein (GP) Ib and integrin alpha2bbeta3 (GPIIb/IIIa) mediated by the ligands von Willebrand factor (VWF), fibrinogen and others. AGGREGATION: Platelets stick to each other through fibrinogen bridging integrin alpha2bbeta3 (GPIIb/IIIa) on adjacent platelets. SECRETION: During activation the content of platelet granules is released by exocytosis, thus augmenting and propagating formation of a haemostatic plug or thrombus. Laboratory tests mimic one or several aspects of these three phases to obtain reliable data on a patients platelet function. In this overview assays, test principles, and pitfalls are presented.

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