Carbon Dioxide in Blood (as Bicarbonate and Carbonic Acid)

What This Test Measures

Blood gases, including CO₂, are critical for keeping your body’s chemistry stable. Your blood carries carbon dioxide from tissues to the lungs, where it’s exhaled. This test checks the total CO₂ content, which includes bicarbonate (a key buffer) and carbonic acid (formed when CO₂ dissolves in blood).

Why It Matters in Your Health

Abnormal CO₂ levels can signal conditions like respiratory issues (e.g., asthma, COPD), metabolic problems (e.g., kidney disease, diabetes), or fluid imbalances. High levels may indicate overproduction of CO₂ (e.g., hyperventilation), while low levels could suggest breathing difficulties or metabolic acidosis.

Common Conditions Affecting Results

This test is often ordered when you have symptoms like shortness of breath, chest pain, confusion, or rapid heartbeat. It may also be used to monitor chronic conditions like heart failure, kidney disease, or severe infections.

Sample Collection and Preparation

A blood sample is taken from a vein (usually in your arm) and sent to a lab for immediate analysis. No special preparation is needed, but fasting may be required depending on the clinical context.