Platelet function testing

Blood platelets contribute to normal haemostasis in two main ways. They adhere to subendothelial microfibrils and collagen in the blood vessel wall, after which they change shape, undergo a specific release reaction, and aggregate with each other to form a primary haemostatic plug. As a consequence of these events, particularly during release and aggregation, procoagulant activities are generated, chiefly involving the platelet membrane phospholipids (platelet factor 3) so that blood coagulation is initiated at, and is largely localised to, the areas ofplatelet aggregation. Quantitative or qualitative platelet disorders may result in a pronounced bleeding tendency, mainly due to failure of platelet plug formation, but also to a lesser extent to the suboptimal activation of blood coagulation. This Broadsheet sets out to describe the methods which can be used reliably to detect and classify such bleeding disorders.