CO2

About This Test
CO₂ (reported as “total CO₂” or bicarbonate) shows how well your body keeps its acid–base balance. The level reflects bicarbonate controlled by the kidneys and carbon dioxide handled by the lungs. Abnormal results can signal problems like dehydration, lung disease, or metabolic issues (e.g., acidosis/alkalosis). This test is commonly included in routine chemistry panels to identify problems early.

Patient Preparation
No fasting needed

Best Time to Test
Anytime

Tests Included
CO2

Why is it done
Evaluation of shortness of breath, hyperventilation, nausea/vomiting, or weakness; assessment of kidney disease, diabetic ketoacidosis, or chronic lung conditions (COPD/asthma); monitoring IV fluids, diuretics, or bicarbonate therapy; follow-up of prior abnormal electrolytes or anion gap.