Prothrombin Time (PT)

How to Subscribe
MLS & MLT Comprehensive CE Package
Includes 176 CE courses, most popular
$109Add to cart
Pick Your Courses
Up to 8 CE hours
$55Add to cart
Individual course$25Add to cart
Need multiple seats for your university or lab? Get a quote
The page below is a sample from the LabCE course Fundamentals of Hemostasis. Access the complete course and earn ASCLS P.A.C.E.-approved continuing education credits by subscribing online.

Learn more about Fundamentals of Hemostasis (online CE course)
Prothrombin Time (PT)

The prothrombin time (PT) is a screening test that helps to assess the functionality of both the extrinsic and common pathways. The effectiveness and presence of factors I, II, V, VII, and X are assayed in this diagnostic test, as they are all found in these two pathways.
PT results are used in conjunction with other diagnostic tests, as well as the clinical picture of the patient, to determine any hemostatic abnormalities that may be present. In addition to being an integral part of the coagulation disorder assessment process, the PT is also used to determine the therapeutic effectiveness of oral anticoagulants by monitoring drugs such as warfarin.
PT test results are reported as the number of seconds needed for a clot to form in the patient specimen using the laboratory's instrument/reagent system; this value can be converted to the International Normalized Ratio (INR).