Diagnosis: Platelet Function Testing: Thromboelastography
• Platelet function studies have historically been used to investigate the cause of unexplained bleeding. The majority of platelet-related bleeding can be attributed to defects of primary hemostasis, such as von Willebrand disease, inherited platelet disorders, and drug-induced platelet dysfunction.
• Platelet function tests are also increasingly used to monitor the therapeutic efficacy of antiplatelet agents used to treat patients at high risk for atherothrombosis.
• The basis of using thromboelastography to evaluate platelet function is to evaluate the contribution of platelets to clot strength in a whole blood samples.
• Advantages of thromboelastography: It measures global coagulation (i.e., clotting factors, platelets, fibrinolysis) and can potentially be used at the point of care (e.g., in the operating room).
• Disadvantages of thromboelastography: To test the platelet-specific contribution to clot formation and strength, additional platelet activators (arachidonic acid or adenosine diphosphate [ADP]) must be used, thereby increasing the complexity of the test.