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Updated: Jul 30, 2025

Leveraging Turbidity and Thromboelastography for Complementary Clot Characterization
Published on: June 4, 2020
Evaluating the Association Between Fibrinogen and Rotational Thromboelastometry and the Progression to Severe
Mary Yurashevich1, Morgan Rosser1, Maria Small2
1Department of Anesthesiology, Duke University School of Medicine, Durham, NC, USA.
Aim:
This study aims to investigate the ability of fibrinogen and rotational thromboelastometry (ROTEM) parameters measured at obstetric hemorrhage protocol initiation to predict severe hemorrhage.
Methods:
In this retrospective study we included patients whose hemorrhage was managed with an obstetric massive transfusion protocol. Fibrinogen and ROTEM parameters EXTEM clotting time (CT), clot formation time (CFT), alpha angle, A10, A20, lysis index 30 min after CT (LI30), FIBTEM A10, A20, were measured at initiation of the protocol with transfusion based on a predefined algorithm. Patients were grouped into either severe or nonsevere hemorrhage based on: peripartum fall in hemoglobin ≥4 g/dL, transfusion of ≥4 units of blood product, invasive procedures for hemorrhage control, intensive care unit admission, or death.
Results:
Of the 155 patients included, 108 (70%) progressed to severe hemorrhage. Fibrinogen, EXTEM alpha angle, A10, A20, FIBTEM A10, A20 were significantly lower in the severe hemorrhage group while the CFT was significantly prolonged in the severe hemorrhage group. In univariate analysis, predicted progression to severe hemorrhage yielded areas under the receiver operating characteristic curve (95% confidence interval [CI]) of: fibrinogen: 0.683 (0.591-0.776), CFT: 0.671 (0.553, 0.789), EXTEM alpha angle: 0.690 (0.577-0.803), A10: 0.693 (0.570-0.815), A20: 0.678 (0.563-0.793), FIBTEM A10: 0.726 (0.605-0.847), and A20: 0.709 (0.594-0.824). In a multivariable model, fibrinogen was independently associated with severe hemorrhage (odds ratio [95% CI] = 1.037 [1.009-1.066]) for every 50 mg/dL decrease in fibrinogen drawn at obstetric hemorrhage massive transfusion protocol initiation.
Conclusion:
Both fibrinogen and ROTEM parameters measured at the initiation of an obstetric hemorrhage protocol are useful parameters for predicting severe hemorrhage.
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