Arterial Blood Gases - ABG, What is it?
Written by Mike Cohen   

Arterial blood gases, called ABGs, are a series of blood measurements that are ordered as a single test. This test is used mainly to check lung function and acid levels in the body.

Who is a candidate for the test?

Any time there is a question about breathing problems, oxygen and carbon dioxide exchange, or acid levels in the body, this test can be helpful.

Examples include:
- people with shortness of breath due to lung problems
- people with rapid breathing due to heart or blood conditions
- people who are unconscious
- people who are suspected of having too much or too little acid in the body, such as someone with kidney failure
- people on artificial breathing machines called ventilators. ABGs are done regularly to assure that the machines are set correctly.

How is the test performed?

A blood sample from an artery is needed to do this test. In most cases, an artery on the palm side of the wrist is used to get the blood. Sometimes, an artery in the groin or other area may be used. The skin over the artery is cleaned first. Next, a small needle is inserted through the skin and into the artery. The needle is usually hooked up to a syringe. Blood flows into the syringe once the needle is put into the artery. Pressure is applied over the area after the blood is collected to prevent bleeding. The blood is then sent to the lab for analysis.