Principles and practice of thromboelastography in clinical coagulation management and transfusion practice.

In the recent years, thromboelastography has become a popular monitoring device for hemostasis and transfusion management in major surgery, trauma, and hemophilia. Thromboelastography is performed in whole blood and assesses the viscoelastic property of clot formation under low shear condition. Thromboelastography can be performed with a variety of activator and inhibitors at different concentrations representing the most important factors for different intervals and clot formation variables reported in multiple studies and algorithms. Furthermore, fibrinogen levels and platelet counts have a major influence on thromboelastographic variables. In addition, differences in patient populations, devices, and preanalytical conditions contribute to some conflicting findings in different studies.