Ankle Brachial Pressure Index
What is an Ankle Brachial Pressure Index (ABI) Test?
This is a test that uses sound waves to measure the blood pressure in your arms and ankles. The higher blood pressure in your arm is compared to the high blood pressure in each of your ankles. Let your nurse know if you are diabetic, have kidney failure, or hyperparathyroidism as these conditions can affect the results of the test.
How does it work?
Blood pressures are taken in each arm and on each ankle using a blood pressure cuff and a small, hand held device called a Doppler. A Doppler lets your nurse hear the pulse in your arteries after the blood pressure cuff is deflated. During the ABI procedure, the Doppler will be pressed against the pulses in your arms, tops of your feet, and inside your ankles.
Why is an ABI done?
The ABI test is done to check for peripheral arterial disease. This is a condition where the arteries in your arms or legs are narrowed. If you have peripheral arterial disease, an ABI can be used to see if your treatment is helping or if another approach may be needed.
Before your ABI
You will be asked to rest in bed for about 10 minutes before the test to allow your blood pressure to normalize (get back to your normal after your previous activity). You will be asked to remove your shoes, socks, and clothes from your upper arms to allow accurate blood pressure readings to be taken.
What happens during the test?
During the test you will be asked to lie on your back while your nurse measures the blood pressures in both your arms and ankles using the Doppler. To help the Doppler work, a gel is applied to the areas where the Doppler will be placed. This may feel cool and a bit moist. The gel will be wiped off at the end of the test.
The nurse will measure your blood pressure on each of your arms. Then the nurse will measure your blood pressure on each of your ankles from two different arteries on top of your foot and the inside of your ankle. This should take about 15 minutes to complete.
What are the risks?
The ABI test is very safe. There are no known risks from sound waves. The test is painless, but you may feel pressure on your arm or ankle while the blood pressure cuff is inflated. This will not last long and should stop when the air is released from the cuff. If you have severe leg or arm pain, let your nurse know as your doctor may want to order a different test.
Your test results__________________________________
Right ABI________________ Left ABI______________
ABI Severity of Disease
>1.40 |
Non-compressible (results not reliable) |
1.00-1.40 |
Normal |
0.91-0.99 |
Borderline |
0.41-0.90 |
Mild to moderate |
0.00-040 |
Severe |
Your doctor will talk to you about the results of the ABI and how they affect your treatment plan. This may be done while you are in the hospital, or at future clinic visit.
The information provided should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Any duplication or distribution of the information contained herein is strictly prohibited.
Last Updated: 02/19/2013
Copyright © 02/19/2013 University of Wisconsin Hospitals and Clinics Authority. All rights reserved. Produced by the Department of Nursing. HF#7062
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