Arterial Blood Gases (ABG) Test


Arterial blood gas is a test to look for gases in the blood.

The Arteries

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Reasons for Test

This test measures the amount of oxygen and carbon dioxide in the blood. It also checks blood acidity (pH). It is often used to see how well the lungs or kidneys are working. It can also check to see if oxygen therapy is helping someone.

Possible Complications

Problems are rare, but all procedures have some risk. The doctor will go over some problems that could happen, such as:

  • Bleeding
  • Bruising
  • Injury to the artery

What to Expect

Prior to Test

The technician may press on arteries in the wrist. This is to check blood flow.

Description of Test

The site will be swabbed clean. The needle will then be inserted into the artery. Blood will be withdrawn. The needle will be removed.

After Test

Gauze will be held on the site to help stop bleeding. You may also be given a bandage. This test takes about 5 to 10 minutes.

How Long Will It Take?

A few minutes

Will It Hurt?

There may be slight pain when the needle is inserted.


Based on the test results, your doctor can assess lung and kidney function.

Call Your Doctor

Call your doctor if you have:

  • Signs of infection, such as fever and chills
  • Bleeding or severe bruising
  • Weakness, tingling, or numbness in hands or feet

If you think you have an emergency, call for medical help right away.


American Association for Respiratory Care
National Heart, Lung, and Blood Institute


The Lung Association


Arterial blood gases (ABG) test. University of Michigan Health website. Available at: Accessed August 27, 2021.
Blood gases. Lab Tests Online—American Association for Clinical Chemistry website. Available at: Accessed August 27, 2021.
Dyspnea—approach to the patient. EBSCO DynaMed website. Available at: Accessed August 27, 2021.
Last reviewed August 27, 2021 by EBSCO Medical Review Board Nicole Meregian, PA
Last Updated: 8/27/2021

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