PT INR (Prothrombin Time)

Also known as Prothrombin Time International Normalized Ratio

₹360

This test is for

Male, Female

Understanding PT INR (Prothrombin Time)

What is PT INR (Prothrombin Time)?

A PT INR (Prothrombin Time) (PT/INR) test helps detect bleeding disorders and monitor the treatment if you are on blood-thinning medicines, such as warfarin. This test also helps to detect liver diseases or check for clotting function before planning surgery.

Prothrombin is a protein and type of clotting (coagulation) factor made by the liver. It helps stop bleeding in case of injuries by forming blood clots. A prothrombin time (PT) helps detect and diagnose a bleeding disorder or an excessive clotting disorder, while the international normalized ratio (INR) is calculated from a PT result and is used to monitor how well blood-thinning medication (anticoagulant), such as warfarin, is working to prevent blood clots.

A PT INR (Prothrombin Time) test can be done if you have symptoms of bleeding or clotting disorders, such as unexplained heavy bleeding, easy bruising, unusual heavy nose bleeds, leg swelling, redness on the legs, or chest pain. Usually, overnight fasting (8-12 hours) is preferred before a PT/INR test, and a duly-filled coagulation requisition form is mandatory for sample collection.

Test result ranges are approximate and may differ slightly between different labs depending on the methodology and laboratory guidelines. Talk to your doctor about your specific test results. Narrate your complete medical history to help the doctor correlate your clinical and laboratory findings. The test results will help them determine your medical condition, make recommendations for lifestyle modifications such as diet and exercise, decide whether or not medication will be required to manage your condition, and formulate your overall treatment plan.

What is PT INR (Prothrombin Time) used for?

A PT INR (Prothrombin Time) test is done:

To detect and diagnose bleeding disorders or clotting disorders.
Before planning a surgical procedure.
To monitor the efficacy of the treatment with anticoagulant medications, such as warfarin.

What does PT INR (Prothrombin Time) measure?

A PT INR (Prothrombin Time) test helps to detect bleeding or clotting disorders. This test measures the time a blood sample takes to clot after chemicals are added to it. INR is a calculation that adjusts the chemicals added to the sample to measure PT and make the test results comparable among different labs.

Interpreting PT INR (Prothrombin Time) results

Interpretations

Prothrombin time longer than the normal range indicates a bleeding disorder where blood takes a longer time to clot.

Prothrombin time shorter than the normal range indicates a clotting disorder where blood takes lesser time to clot.

The PT and aPTT tests are usually performed and evaluated simultaneously, and the results may be interpreted as follows:

PT RESULT	aPTT RESULT	CONDITIONS INDICATED
High	Normal	Liver diseases, Vitamin K deficiency, reduced activity of Factor VII, Disseminated Intravascular Coagulation (DIC), Warfarin treatment
Normal	High	Reduced activity of Factors VIII, IX, XI, or XII, Von Willebrand disease, autoantibodies destroying one or more coagulation factors
High	High	Reduced activity of Factors I, II, V or X, liver diseases, DIC, an overdose of Warfarin
Normal	Normal	Normal hemostasis usually. However, normal results may also appear in a mild reduction in coagulation factor activity and mild cases of Von Willebrand disease.

Answers to Patient Concerns & Frequently Asked Questions (FAQs) about PT INR (Prothrombin Time)

Frequently Asked Questions about PT INR (Prothrombin Time)

Q. How is a PT/INR test performed?

Your doctor will clean the skin using an antiseptic alcohol cotton swab or wipe and take out a blood sample from your veins using a needle. The blood sample will be stored safely and transported to the lab for analysis.

Q. Is there any risk associated with a PT/INR test?

There is usually no risk associated with this test. However, some people may feel a slight sting when a needle is pricked and experience some bleeding that is normal and usually not bothersome. Rarely, some people may also experience slight swelling or bruising at the site of the needle prick. Applying ice 3-4 times a day for about a week may help reduce swelling and bruising. If it does not get better, consult your doctor.

Q. What are some apparent symptoms of bleeding or clotting disorders?

Visible symptoms of bleeding or clotting disorders include unexplained heavy bleeding, abnormal menstrual bleeding in women, easy bruising and bleeding, frequent nosebleeds, bleeding gums, and repeated heart attacks or strokes.

Q. What other tests can be performed along with a PT/INR test?

Liver tests such as aspartate aminotransferase (AST) and alanine aminotransferase (ALT) can be performed along with a PT/INR test.

Q. What conditions can affect blood clotting to cause bleeding disorders?

Certain inherited conditions such as hemophilia, clotting factor deficiency, vitamin K deficiency, liver diseases, bone marrow disorders, von Willebrand disease, and cancers like leukemia can cause bleeding disorders.

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