Seminars in thrombosis and hemostasis
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Semin. Thromb. Hemost. · Oct 2010
ReviewCritical factors contributing to the thromboelastography trace.
The thromboelastography trace provides a graphical and numerical representation of the viscoelastic changes associated with fibrin polymerization. When used with whole blood, the shape of this trace is a composite of the effects of white and red cell content and composition, platelet number and function, fibrinogen concentration, as well as coagulation protein function and balance. The trace is also influenced by pharmacological agents such as anticoagulants, antiplatelet therapy, and coagulation factor supplementation. ⋯ New applications for pharmaceutical monitoring and patient screening are being explored. This review gives a broad overview of the applications of the technology. In particular it considers the factors that most influence the characteristics of the trace, be they preanalytical, analytical, or clinical.
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Semin. Thromb. Hemost. · Oct 2010
ReviewCoagulation abnormalities in the trauma patient: the role of point-of-care thromboelastography.
Current recommendations for resuscitation of the critically injured patient are limited by a lack of point-of-care (POC) assessment of coagulation status. Accordingly, the potential exists for indiscriminant blood component administration. Furthermore, although thromboembolic events have been described shortly after injury, the time sequence of post-injury coagulation changes is unknown. ⋯ Thromboelastography (TEG), a time-sensitive dynamic assay of the viscoelastic properties of blood, closely parallels the CBM, permitting timely, goal-directed restoration of hemostasis via POC monitoring of coagulation status. TEG-based therapy allows for goal-directed blood product administration in trauma, with potential avoidance of the complications resulting from overzealous component administration, as well as the ability to monitor post-injury coagulation status and thromboprophylaxis. This overview addresses coagulation status and thromboprophylaxis management in the trauma patient and the emerging role of POC TEG.
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Semin. Thromb. Hemost. · Oct 2010
ReviewQuality assurance and quality control of thrombelastography and rotational Thromboelastometry: the UK NEQAS for blood coagulation experience.
Global hemostasis devices are currently being employed in operating rooms to assess the bleeding risk and outcomes for patients undergoing surgery. Two devices currently available are the TEG (Thromboelastograph; Haemoscope Corp., Niles, IL) and the ROTEM (Rotation Thromboelastometer; Pentapharm GmbH, Munich, Germany). Both measure the speed of clot formation, the strength of the clot when formed, and clot fibrinolysis kinetics. ⋯ The precision of the tests varied greatly for both devices, with coefficients of variances ranging from 7.1 to 39.9% for TEG and 7.0 to 83.6% for ROTEM. Some centers returned results that were sufficiently different from those obtained by other participants to predict alterations in patient management decisions. Our data indicate that regular EQA/proficiency testing is needed for these devices.
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Semin. Thromb. Hemost. · Oct 2010
ReviewClinical utility of thromboelastography: one size does not fit all.
Coagulation management requires the balancing of different components that contribute to clot formation. These components include the interactions between platelets, procoagulant, anticoagulant, and fibrinolytic factors. ⋯ In contrast, thromboelastography is a test that monitors the different phases of clot formation and lysis, providing the clinician with a tool for making informed therapeutic decisions. This review provides an overview of thromboelastography in the management of hypocoagulable and hypercoagulable conditions.
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Semin. Thromb. Hemost. · Oct 2010
ReviewStandardization of thromboelastography: values and challenges.
Laboratory evaluation of hemostasis has been performed using plasma for several decades. The cell-based model of coagulation has now led to renewed interest in the global assays of coagulation such as thrombin generation and thromboelastography. These tests have remained as research tools, however, because of the lack of studies to demonstrate their reliability. ⋯ It is therefore critical to standardize the assay to achieve clinical relevance. This article summarizes the TEG-ROTEM Working Group's efforts to try and standardize thromboelastography and the challenges faced in this process. Although this has been the first effort to standardize this test, it is extremely important to continue this work, so that we may investigate the usefulness and possible applications of thromboelastography in evaluating the process of hemostasis.