Carbon Dioxide (Total) in Blood Gas Analysis

What Does This Test Measure?

Total carbon dioxide (CO₂) in your blood includes both dissolved CO₂ and bicarbonate (HCO₃⁻), which are key components of your body’s acid-base balance. This test helps evaluate how efficiently your lungs remove CO₂ and how your kidneys adjust bicarbonate levels to maintain normal pH.

Why Might You Need This Test?

Doctors may order this test if you have symptoms like shortness of breath, chest pain, or fatigue, which could indicate problems with your lungs or kidneys. It’s also used during monitoring for conditions like heart failure, kidney disease, or severe infections.

Sample Collection and Preparation

This test requires a blood sample drawn from a vein, usually in your arm. The blood is analyzed immediately or sent to a lab to measure total CO₂ levels, often as part of a broader blood gas panel that also checks oxygen and pH levels.

What Are Common Results and Interpretation?

Results are typically reported alongside blood pH and oxygen levels to determine whether your acid-base balance is normal or if adjustments are needed. Elevated CO₂ levels may suggest respiratory issues, while low levels could indicate metabolic problems or overbreathing.