Basically, a blood test that tells us how long it takes for your blood to clot. Used frequently to determine if there is a bleeding disorder, to monitor patients on Coumadin (a common anticoagulant), or prior to surgery to insure one has the ability to clot normally.
Why should I have a Prothrombin Time Test?
- If you have unexplained bruising or bleeding
- If you are on the blood-thinner (anti-coagulant) Coumadin, or
- If you are planning to have surgery
Reference Range(s)
PT: 9.0-11.5 sec
INR:
| Reference range | 0.9-1.1 |
| Moderate – intensity Warfarin therapy | 2.0-3.0 |
| Higher – intensity Warfarin therapy | 3.0-4.0 |
Clinical Significance Screening test for abnormalities of coagulation factors that are involved in the extrinsic pathway. Also used to monitor effects of Warfarin therapy and to study patients with hereditary and acquired clotting disorders.
Aliases: PT
If you have an elevated Prothrombin Time you should consult your physician immediately.
However, if you are on the “blood-thinner” Coumadin you are expected to have an elevated PT within the following range:
On anticoagulant medications: 2.0 – 3.0