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Common causes of a low HCO₃⁻ (Arterial Bicarbonate)
- Metabolic acidosis
- Compensation for respiratory alkalosis
Looking for the other direction? See what causes a high HCO₃⁻ (Arterial Bicarbonate).
All tests · Arterial Blood Gas (ABG) · HCO₃⁻ (Arterial Bicarbonate)
Below the range
What causes a low HCO₃⁻ (Arterial Bicarbonate)?
Normal range 22-26 mEq/L (22-26 mmol/L SI). Specimen: Arterial blood (calculated). See the full HCO₃⁻ (Arterial Bicarbonate) reference page for critical values and nursing considerations.
What is the normal range for HCO₃⁻ (Arterial Bicarbonate)?
The standard teaching reference range for HCO₃⁻ (Arterial Bicarbonate) is 22-26 mEq/L in conventional units, or 22-26 mmol/L in SI units. This value is measured in arterial blood (calculated).
| Specimen | Arterial blood (calculated) |
|---|---|
| Conventional range | 22-26 mEq/L |
| SI range | 22-26 mmol/L |
| Critical value | < 15 or > 40 mEq/L |
| Panel | Arterial Blood Gas (ABG) |
Full details, including nursing considerations, on the HCO₃⁻ (Arterial Bicarbonate) normal range page. Reference ranges vary by laboratory, method, age, sex, and population - always use the range printed on the actual result.
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