Metabolic alkalosis is defined by HCO3- above which value?

• A. 22 mEq/L
• B. 26 mEq/L
• C. 30 mEq/L
• D. 24 mEq/L

Answer: (B)

Metabolic alkalosis is a state where the buffering system is tipped toward excess base, causing the serum pH to rise. The key marker is bicarbonate in the blood. The normal upper limit for HCO3− is about 26 mEq/L, so values above 26 indicate metabolic alkalosis. This means a bicarbonate of 30 mEq/L fits the diagnosis, while values like 22 or 24 are still within the normal range and do not indicate alkalosis. Higher bicarbonate numbers reflect a stronger alkalotic state, but the diagnostic threshold remains 26 mEq/L.