Synonyms: CO2; total carbon dioxide, TCO2

Why It Is Done

Determine the lungs ability to release carbon dioxide . The function of your kidneys . Metabolic problems The ability of your body to maintain a normal blood pH.

Test Overview

A carbon dioxide test measures the total amount of the three forms of carbon dioxide (bicarbonate, carbonic acid, and dissolved carbon dioxide) in your blood.

Carbon dioxide (CO2) is a gaseous waste product made from metabolism. The blood carries carbon dioxide to your lungs, where it is exhaled. More than 90% of carbon dioxide in your blood exists in the form of bicarbonate (HCO3). The remainder of the carbon dioxide is either dissolved carbon dioxide gas (CO2) or carbonic acid (H2CO3).

Your kidneys and lungs regulate the levels of carbon dioxide, bicarbonate, and carbonic acid in the blood.

How To Prepare

No special preparation is necessary