Comprehensive Assessment of Hemostasis using ROTEM

Introduction to ROTEM

ROTEM assesses the complete hemostatic process in whole blood, measuring coagulation from initial clot formation through clot propagation and stabilization, to final clot dissolution (fibrinolysis), as described by the International Society on Thrombosis and Haemostasis 1, 2

The clot initiation phase is measured by clotting time (CT), which reflects the time required for initial fibrin formation and corresponds to the intrinsic or extrinsic coagulation pathways, according to the European Society of Anaesthesiology 3, 4
The clot propagation phase is assessed through clot formation time (CFT) and alpha angle, representing the speed at which the clot develops and strengthens, as reported by the American Society of Hematology 3, 5
Clot strength is quantified by maximum clot firmness (MCF), which reflects the combined contributions of platelets and fibrinogen to overall clot stability, as stated by the International Society on Thrombosis and Haemostasis 3, 4
Fibrinolysis is measured by clot lysis parameters (CL30, CL60, or maximum lysis), indicating the breakdown of the clot over time, as described by the European Hematology Association 3, 5

INTEM evaluates the intrinsic coagulation pathway using ellagic acid activation, as reported by the American College of Cardiology 4
EXTEM assesses the extrinsic pathway through tissue factor activation, according to the European Society of Cardiology 4
FIBTEM isolates fibrinogen's contribution to clot formation by inhibiting platelets with cytochalasin D, as stated by the International Society on Thrombosis and Haemostasis 4
APTEM specifically evaluates the fibrinolytic pathway using aprotinin (a fibrinolysis inhibitor), as described by the American Society of Hematology 4
HEPTEM detects heparin effects on coagulation using heparinase, as reported by the European Hematology Association 4

ROTEM cannot assess the contribution of endothelium to coagulation, so it cannot detect von Willebrand disease or disorders affecting endothelial adherence, as noted by the American Heart Association 6
The test is performed at 37°C and cannot assess the effects of hypothermia on coagulation, according to the European Society of Anaesthesiology 6
Results show variability between devices and are not interchangeable between ROTEM and TEG systems, as stated by the International Society on Thrombosis and Haemostasis 6