What you can expect

During the test

Obtaining the blood sample for prothrombin time testing usually takes just a few minutes, like any other blood test.

After the test

Your blood might be sent to a laboratory for analysis. If the laboratory analysis is done on-site, you could have your test results within hours. If your doctor sends your blood to an off-site laboratory, it may take several days to receive the results.

In some anticoagulation clinics, a nurse will take a sample of your blood with a finger stick, and give you the test result within minutes, while you are still in the exam room.

Home testing

Home testing kits are available for people who have to take blood thinners for long periods and who have been trained in taking blood samples and testing them.

Nov. 24, 2015
References
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  2. AskMayoExpert. Cardiac surgery excessive bleeding. Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2014.
  3. Drews RE. Approach to the adult patient with a bleeding diathesis. http://www.uptodate.com/home. Accessed Sept. 16, 2015.
  4. PT and INR. Lab Tests Online. http://www.labtestsonline.org/understanding/analytes/pt/glance.html#. Accessed Sept. 16, 2015.
  5. Bambha K, et al. Model for end-stage liver disease (MELD). http://www.uptodate.com/home. Accessed Sept. 16, 2015.
  6. AskMayoExpert. Abnormal liver tests (adult). Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2014.
  7. Cameron JL, et al, eds. Coagulopathy in the critically ill patient. In: Current Surgical Therapy. 11th ed. Philadelphia, Pa.: Saunders Elsevier; 2014. http://www.clinicalkey.com. Accessed Sept. 16, 2015.
  8. Litin SC (expert opinion). Mayo Clinic, Rochester, Minn. Oct. 7, 2015.
  9. Prothrombin time. Mayo Medical Laboratories. http://www.mayomedicallaboratories.com/test-catalog/Clinical+and+Interpretive/9236. Accessed Sept. 16, 2015.
  10. AskMayoExpert. Monitoring anticoagulation effects of warfarin (adults). Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2015.