Given Na 140 mEq/L, Cl 106 mEq/L, and HCO3 20 mEq/L, what is the anion gap?

Given Na 140 mEq/L, Cl 106 mEq/L, and HCO3 20 mEq/L, what is the anion gap?

• A. 6 mEq/L
• B. 14 mEq/L
• C. 24 mEq/L
• D. 34 mEq/L

Answer: (B)

The anion gap is calculated to estimate unmeasured anions in the blood and is found by subtracting the sum of chloride and bicarbonate from the sodium: Na − (Cl + HCO3). With the values given, 140 − (106 + 20) = 140 − 126 = 14 mEq/L. This falls in the normal range (roughly 8–12 mEq/L, with some labs up to about 14 if potassium isn’t included), so the result indicates a normal anion gap. If potassium were included in the calculation, the normal range shifts slightly, but the computed gap here clearly aligns with normal.

The anion gap is calculated to estimate unmeasured anions in the blood and is found by subtracting the sum of chloride and bicarbonate from the sodium: Na − (Cl + HCO3). With the values given, 140 − (106 + 20) = 140 − 126 = 14 mEq/L. This falls in the normal range (roughly 8–12 mEq/L, with some labs up to about 14 if potassium isn’t included), so the result indicates a normal anion gap. If potassium were included in the calculation, the normal range shifts slightly, but the computed gap here clearly aligns with normal.