Carbon Monoxide (CO)
A carbon monoxide blood test is used to detect
carbon monoxide poisoning. Poisoning can happen if you breathe air that contains too much carbon monoxide (CO). This gas has no color, odor, or taste, so you can't tell when you are breathing it. The test measures the amount of hemoglobin
in your blood that has bonded with carbon monoxide.
Carbon monoxide can come from any source that burns fuel. Common sources are cars, fireplaces, powerboats, woodstoves, kerosene space heaters, charcoal grills, and gas appliances such as water heaters and ovens. These things usually cause no problems. But if they are not used or installed properly, carbon monoxide may build up in an enclosed space.
When you inhale carbon monoxide ,
it replaces the oxygen that is normally carried by the hemoglobin in your red blood cells. As a
result, your brain and other tissues get less oxygen. This can cause serious symptoms or death.
Why It Is Done
This test may be done if
you have been exposed to carbon monoxide or if you have unexplained symptoms, such
- Headache, dizziness, or vision
- Nausea or vomiting.
- Confusion or trouble thinking.
How To Prepare
Do not smoke before you have this
test. Tobacco smoke contains carbon monoxide.
Talk to your doctor if you have any concerns about
the need for the test, its risks, how it will be done, or what the results may
mean. To help you understand the importance of this test, fill out the
medical test information form(What is a PDF document?).
How It Is Done
The health professional taking a sample of your blood
- Wrap an elastic band around your upper arm to
stop the flow of blood. This makes the veins below the band larger so it is
easier to put a needle into the vein.
- Clean the needle site with
- Put the needle into the vein. More than one needle stick
may be needed.
- Attach a tube to the needle to fill it with
- Remove the band from your arm when enough blood is
- Put a gauze pad or cotton ball over the needle site as
the needle is removed.
- Put pressure on the site and then put on a