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In Vitro Thrombosis Test for Ventricular Assist Devices
Published on: March 21, 2025
Use of viscoelastic haemostatic assay in emergency and elective surgery
Maximus C F Yeung1, Steven Y T Tong1, Paul Y W Tong1
1Department of Surgery, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital, Pokfulam, Hong Kong.
Objectives:
To review the current evidence for the use of viscoelastic haemostatic assays in different surgical settings including trauma, cardiac surgery, liver transplantation, as well as the monitoring of antiplatelet agents and anticoagulants prior to surgery.
Data Sources:
PubMed database.
Study Selection:
Key words for the literature search were "thromboelastography" or "ROTEM" in combination with "trauma", "antiplatelet", "cardiac surgery", "liver transplantation" or "anticoagulants".
Data Extraction:
Original and major review articles related to the use of viscoelastic haemostatic assays.
Data Synthesis:
Haemostatic function is a critical factor determining patient outcomes in emergency or elective surgery. The increasing use of antiplatelet agents and anticoagulants has potentially increased the risks of haemorrhages and the need for transfusion. Conventional coagulation tests have limitations in detecting haemostatic dysfunctions in subgroups of patients and are largely ineffective in diagnosing hyperfibrinolysis. The viscoelastic haemostatic assays are potentially useful point-of-care tools that provide information on clot formation, clot strength, and fibrinolysis, as well as to guide goal-directed transfusion and antifibrinolytic therapy. They may also be used to monitor antiplatelet and anticoagulant therapy. However, standardisation of techniques and reference ranges is required before these tests can be widely used in different clinical settings.
Conclusions:
Viscoelastic haemostatic assays, as compared with conventional coagulation tests, are better for detecting coagulopathy and are the only tests that can provide rapid diagnosis of hyperfibrinolysis. Goal-directed administration of blood products based on the results of viscoelastic haemostatic assays was associated with reduction in allogeneic blood product transfusions in trauma, cardiac surgery, and liver transplantation cases. However, there is currently no evidence to support the routine use of viscoelastic haemostatic assays for monitoring platelet function prior to surgery.
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