Coagulation Testing- PT
Prothrombin Time assay (PT):
Pathways
measured:
Clotting
factors monitored:
Clotting factors not monitored that are in these pathways:
Extrinsic pathway
Common pathway
VII, X, V, I, and II
III, IV, PF3, and XIII
Why
these are not measured:
III, IV, PF3:
Substitutes added in reagent
XIII
Instrument detects fibrin monomer formation and
stops