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What will doctors do with this test?
Doctors often need to compare the results of a prothrombin time test with others, especially partial thromboplastin time. They will use this test to diagnose what is causing your bleeding episodes, why is blood clotting spontaneously in your veins and arteries, and how is your liver working as a synthesis center of coagulation factors.
If you’re receiving warfarin or another anticoagulant medication, you might need an additional calculation known as the international normalized ratio (INR). They are both fundamental to monitor the effectiveness of blood-thinning therapy.
Along with partial thromboplastin time, this test is mostly used to evaluate clotting disorders. It is beneficial when patients have spontaneous bleeding episodes and give clues as to their source. However, they are not diagnostic tests and do not hold the final answer.
Additional tests can be performed in patients with bleeding episodes, including a platelet count, fibrinogen tests, and more complicated tests such as the von Willebrand factor and lupus anticoagulant testing, useful for further investigations in patients with a prolonged coagulation time.
