Emergency assessment of hemostasis in the bleeding patient

W L Chandler1

  • 1Department of Pathology and Genomic Medicine, The Methodist Hospital, Houston, TX 77030, USA. wlchandler@tmhs.org

Emergency hemostasis testing is typically used to determine which blood products are needed to correct hemostatic defects associated with bleeding. Rapid assessment of hemostasis can be performed using standard or viscoelastic hemostasis tests in the clinical laboratory, satellite laboratory, or using point-of-care methods. The major drawback of standard coagulation testing is that most clinical laboratories are focused more on accuracy than on turnaround time. Improving turnaround times may require revision of the entire approach to performing the testing in the clinical laboratory including specimen processing, testing, and reporting. An advantage to rapid central laboratory testing is the availability to all areas of the hospital, not just the emergency department or operating rooms. Use of point-of-care assays can improve turnaround times, but point-of-care tests typically show more variation and lower precision. Viscoelastic global hemostasis tests can be used for rapid assessment as well, but care needs to be taken in the interpretation of the results. Viscoelastic testing is currently the only method that can detect severe fibrinolysis. Platelet function testing is useful for detection of hereditary platelet function problems and some antiplatelet medication monitoring, but is less useful for preoperative bleeding risk assessment or diagnosing the cause of acquire bleeding syndromes. This review will highlight different approaches to the rapid assessment of hemostasis.

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