International Normalized Ratio
(INR)

Is a type of calculation based on PT test results? Prothrombin is a protein made by the liver. It is one of several substances known as clotting (coagulation) factors

- Sample type:

Blood should be collected in a blue-top tube containing 3.2% buffered sodium citrate.

- Uses:

It is used to monitor blood-thinning medicines, which are also known as anticoagulants. The INR, or international normalized ratio, can also be used to check if you have a blood clotting problem.

- Precautions:

1) Avoid medicines that thin blood and increase bleeding risk, such as aspirin, Naprosyn and ibuprofen.

2) Take care with contact sports and activities that can cause injuries, bruising and bleeding.

3) Minimize contact with toxic chemicals.

4) Avoid prolonged use of a tourniquet

- Interfering factors:

1) Vitamin K consumption,

2) drug interactions,

3) herbs interactions

4) disease states,

5) alcohol intake

6) And thus warfarin dosing.

- Pre analytical errors:

1) .Use errors specimen collected and those unrelated to order

2) .Entry insufficient specimen quantity

3) Or specimen-integrity concerns).

- Corrective action:

Vitamin K is a safe and effective antidote to warfarin. Both oral and intravenous (IV) routes are effective in reducing a raised INR due to warfarin with a similar correction of INR by 24 hrs. IV has a more rapid response, within 6-8 hours. Anaphylaxis to IV vitamin K is rare.

- Post analytical errors:

Sample storage and disposal

Archiving of laboratory documentation

Post-analytical quality indicators

- Reference rang :

In healthy people an INR of 1.1 or below is considered normal.

An INR range of 2.0 to 3.0 is generally an effective therapeutic range for people taking warfarin for disorders