What is the reference range for Total Carbon Dioxide (Bicarbonate)?

The standard reference range for Total Carbon Dioxide (Bicarbonate) is Approximately 22–29 mmol/L; assay-specific.. Reference ranges vary by laboratory and assay platform — interpret in context of the issuing laboratory's stated range.

Which tests measure Total Carbon Dioxide (Bicarbonate)?

Total Carbon Dioxide (Bicarbonate) is measured in 1 test on BiomarkersLabs.com, including Basic Metabolic Panel without Calcium.

Biomarker Reference · CO₂

What does the Total Carbon Dioxide (Bicarbonate) test measure?

Total Carbon Dioxide (Bicarbonate) (CO₂) is a clinical biomarker used in metabolic-diabetes assessment. Total CO₂ represents serum bicarbonate plus dissolved carbon dioxide, with bicarbonate comprising more than 95 per cent in venous samples at physiological pH. It is measured in 1 laboratory test on BiomarkersLabs.com.

Reference Range: Approximately 22–29 mmol/L; assay-specific.
Units: mmol/L, mEq/L
Measured In: 1 test
Category: Metabolic

Functional medicine optimal24–26 mmol/L is often cited as the midpoint of the reference range; both extremes require interpretation with pH and anion gap when available.

What is Total Carbon Dioxide (Bicarbonate)?

Total CO₂ represents serum bicarbonate plus dissolved carbon dioxide, with bicarbonate comprising more than 95 per cent in venous samples at physiological pH. Bicarbonate is the principal extracellular buffer, regulated by renal retention and excretion in response to metabolic and respiratory acid-base disturbances.

Why is Total Carbon Dioxide (Bicarbonate) measured?

Low bicarbonate signals metabolic acidosis (renal failure, ketoacidosis, lactic acidosis, renal tubular acidosis) or respiratory alkalosis with renal compensation. High bicarbonate suggests metabolic alkalosis (vomiting, diuretic use, volume contraction) or compensated respiratory acidosis. The anion gap and clinical context are essential to distinguish causes.

Reference ranges

Standard reference: Approximately 22–29 mmol/L; assay-specific.
Functional medicine optimal: 24–26 mmol/L is often cited as the midpoint of the reference range; both extremes require interpretation with pH and anion gap when available.
Units: mmol/L, mEq/L

Reference ranges vary by laboratory and assay platform. Interpret in context of the issuing laboratory's stated range.

Tests that measure Total Carbon Dioxide (Bicarbonate)

1 test on BiomarkersLabs.com include this biomarker.

BML-MET-021Comprehensive

Basic Metabolic Panel without Calcium

Total Carbon Dioxide (Bicarbonate) reference range in this test: Approximately 22–29 mmol/L; assay-specific.

Related clinical conditions

Related Biomarkers

Frequently measured alongside

SodiumNa6 tests PotassiumK6 tests ChlorideCl6 tests Blood Urea NitrogenBUN2 tests Serum CreatinineCr6 tests GlucoseGluc6 tests BUN:Creatinine RatioBUN:Cr3 tests

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