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Updated: Apr 11, 2026

Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay
Published on: September 9, 2012
Viscoelastic hemostatic fibrinogen assays detect fibrinolysis early
Purpose:
Viscoelastic hemostatic assays are emerging as the standard-of-care in the early detection of post-injury coagulopathy. TEG and ROTEM are most commonly used. Although similar in technique, each uses different reagents, which may affect their sensitivity to detect fibrinolysis. Therefore, the purpose of this study is to determine the ability of each device to detect fibrinolysis.
Methods:
TEG (Rapid, Kaolin, Functional Fibrinogen) and ROTEM (EXTEM, INTEM, FIBTEM) were run simultaneously on normal blood as well as blood containing tPA from healthy volunteers (n = 10). A two-tailed, paired t-test and ANOVA were used to determine the significance between parameters obtained from normal blood and blood with tPA, and individual TEG and ROTEM assays, respectively.
Results:
TEG detected significant changes in clot strength and 30-min lysis after the addition of tPA (p < 0.0001). All ROTEM assays detected changes in the 30-min lysis (p < 0.0001), but only INTEM detected changes in clot strength (p < 0.05). Kaolin and Rapid TEG assays detected greater changes in clot strength and lysis, but INTEM and EXTEM had decreased lysis onset times compared to TEG (p < 0.001). Functional Fibrinogen and FIBTEM assays detected lysis sooner than other TEG/ROTEM assays, and were comparable.
Conclusions:
TEG assays detect greater changes in clot strength compared to ROTEM. Despite this, Functional Fibrinogen and FIBTEM assays detect fibrinolysis sooner than their corresponding intrinsic and extrinsic assays. Therefore, fibrinogen assays should be employed in actively bleeding trauma patients in order to provide timely antifibrinolytic therapy.
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