Arterial Blood Gases Overview
This is a blood test to identify levels of certain gases in the blood.
: image/57 "The Arteries" center
Based on the test results, your doctor can assess your lung and kidney function.
What to Expect
#Prior to Test
If the blood is going to be taken from an artery in the arm, an Allen test will be done. This test will be used to evaluate blood circulation. During the Allen test, the technician will press the radial and ulnar arteries in the wrist. This will cause your palm to turn white. When the arteries are released, the skin will turn pink and flushed. If your skin does not flush within five seconds, this will indicate that you have decreased blood flow to your palm. Another puncture site will need to be chosen.
#Description of Test
The puncture site will be swabbed clean. The needle will then be inserted into the selected artery. Blood will be withdrawn. The needle will be removed.
The technician will put pressure on the puncture site for about five minutes. If you take a blood-thinning medicine, it may take longer for the bleeding to stop. Once the bleeding has stopped, a bandage will be placed on the site. You will leave the bandage in place for 30-60 minutes. You will need to keep the site clean.
#How Long Will It Take?
A few minutes
#Will It Hurt?
It may hurt slightly when the needle is inserted.
American Association for Respiratory Care
National Heart, Lung, and Blood Institute
The Canadian Lung Association
American Association for Respiratory Care website. Available at: