Explain the clinical significance of a prolonged time with each of the following:

Question

a. Bleeding time
b. Prothrombin time
c. Activated partial thromboplastin time
d. Thrombin time

What will be an ideal response?

Answer 1

Answer:
Bleeding time: Indicates a potential problem with platelet function. A platelet count in conjunction with a bleeding time would give more information about whether this is a platelet production problem or a platelet function problem. Prolonged bleeding times can be seen in patients with von Willebrand's disease, aspirin intake, and quantitative and qualitative platelet disorders.
Prothrombin time: Indicates a potential problem with the extrinsic pathway and/or common pathway. The PT is also used to monitor Coumadin therapy (along with the INR). Prolonged PT can be seen in factor VII deficiency.
Activated partial thromboplastin time: Indicates a potential problem with the intrinsic pathway and/or common pathway. The APTT is also used to monitor heparin therapy. Prolonged APTT can be seen in hemophilia patients and VWD patients
Thrombin time: Indicates a potential problem with conversion of fibrinogen to fibrin. It is also extremely sensitive to heparin contamination.