The CO2 blood test results tell us whether the amount of carbon dioxide in our blood is within the typical range. A number higher or lower than the typical range may indicate a problem with kidneys or lungs.

Measurement of total CO2 content can help us explain acid–base disorders

23 to 30 mEq/L

The Total Carbon Dioxide (TCO2) test, also known as bicarbonate or serum CO2 test, measures the total amount of carbon dioxide (CO2) dissolved in the blood, mainly in the form of bicarbonate (HCO3-). Here's how to interpret the results: Normal Range: The normal range for TCO2 levels typically falls between 23 to 29 milliequivalents per liter (mEq/L) or 23 to 29 millimoles per liter (mmol/L). However, normal ranges can vary slightly between laboratories due to differences in measurement techniques and reference populations. Interpretation: Low TCO2 Levels (Hypocapnia): Low TCO2 levels may indicate metabolic acidosis, which can result from conditions such as diabetic ketoacidosis, lactic acidosis, renal failure, severe diarrhea, or poisoning. Hypocapnia may also occur due to respiratory alkalosis, characterized by excessive exhalation of CO2, which can result from hyperventilation, anxiety, fever, or certain medications. High TCO2 Levels (Hypercapnia): High TCO2 levels may indicate metabolic alkalosis, which can result from conditions such as vomiting, gastric suctioning, excessive use of antacids, or potassium depletion. Hypercapnia may also occur due to respiratory acidosis, characterized by inadequate elimination of CO2, which can result from conditions such as hypoventilation, chronic obstructive pulmonary disease (COPD), asthma exacerbation, or drug overdose. Clinical Correlation: Interpretation of TCO2 levels should be done in conjunction with the patient's clinical history, symptoms, and other laboratory tests. Additional diagnostic tests, such as arterial blood gas (ABG) analysis, electrolyte panel, and renal function tests, may be necessary to determine the underlying cause of acid-base disturbances.

Blood