thromboelastography

THROMBOELASTOGRAPHY

TEG Principle

TEG Parameters

r time

• Time from initiation of trace until the amplitude of the trace reaches 2 mm

• Corresponds to initial fibrin formation

• Functionally related to plasma clotting and inhibitor activity

TEG Parameters

r time ↑ by

Factor deficiency Anti-coagulation Severe

hypofibrinogenaemia Severe thrombocytopenia

r time ↓ by

Hypercoagulability syndromes

TEG Parameters

K time

• Time from r until amplitude reaches 20 mm

• Measure of clot formation kinetics

angle

• Measures the rapidity of fibrin polymerization

• assesses rate of clot formation

TEG Parameters

k time ↑ or angle ↓by

Factor deficiency Hypofibrinogenaemia Thrombocytopenia

k time↓ or angle ↑ by

Hypercoagulability state

TEG ParametersMaximum amplitude

• is a direct function of the maximum dynamic properties of fibrin and platelet bonding

• represents the maximum strength of the fibrin clot

• Correlates more to platelet function and to lesser extent to fibrinogen

MA ↓ by

Thrombocytopenia

Thrombocytopathy

Fibrinolysis

Hypofibrinogenemia

TEG ParametersLY30

• measures % decrease in amplitude 30 min post-MA

• gives measure of degree of fibrinolysis

• normal range < 7.5%

LY60

60 minute post-MA data

Factor Deficiency

Heparin effect

Thrombocytopenia

Fibrinolysis

Hypercoagulable

Severe Coagulopathy

Heparin Effect