Deficiencies may be congenital or acquired secondary to liver disease, warfarin anticoagulation, disseminated intravascular coagulation, or massive replacement with red blood cells and crystalloid/colloid solutions. FFP should not be used for Hemophilia B (Factor IX) deficiency unless Factor IX concentrate is not available. FFP, but not thawed plasma, can be used for Factor V deficiency. Recombinant or Factor VIII concentrates should be used to replace Factor VIII.
Usually, there is an increase of at least 1.5 times the normal PT or PTT, or an INR ≥ 1.6 before clinically important factor deficiency exists. This corresponds to factor levels