Routine coagulation tests

PT (Prothrombin Time) test

These tests include PT (prothrombin time), APTT (partial thromboplastin time), fibrinogen, and TT (thrombin time).

• PT test is performed to assess the deficiency and inhibitors of extrinsic factors (eg: Factor VII) and total factors (eg: Factor X, V, II, fibrinogen).

• PT measurement

The PT reagent is a source of tissue factor (also known as thromboplastin), phospholipids, and calcium chloride. The plasma is heated to 37 °C, pre-warmed PT reagent is added and the time for clot formation is measured in seconds. PT values depend on the reagents and equipment used and are determined by laboratories themselves. A normal PT is about 9-15 seconds.