The thrombin time (TT) is a blood test that measures the time it takes for a clot to form in the plasma of a blood sample containing anticoagulant, after an excess of thrombin has been added. It is used to diagnose blood coagulation disorders and to assess the effectiveness of fibrinolytic therapy.
Blood clotting is an important step in healing from an injury, such as a cut. Forming a blood clot is a complicated process. It involves many blood components that must interact in a specific order.
Thrombin time is a measure of how long the blood's plasma, or the liquid portion of the blood, takes to form a clot. This test gives information about how well one particular blood component called fibrinogen is working.
A normal thrombin time is 11.3 to 18.5 seconds.
Thrombin time
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