Thrombin Time (TT)

Measures the adequacy of the COMMON PATHWAY i.e. the conversion of fibrinogen to fibrin catalysed by thrombin. Thrombin is added directly to plasma at 37°C thus by-passing the intrinsic and extrinsic systems.
The patient's thrombin time is then compared to a normal or control plasma sample which is tested at the same time.
Normal TT: 10 - 12 seconds.