ABG interpretation: pH 7.51; pCO2 40; HCO3- 38. Which pattern best fits this result?

ABG interpretation: pH 7.51; pCO2 40; HCO3- 38. Which pattern best fits this result?

• A. Uncompensated metabolic alkalosis
• B. Compensated metabolic alkalosis
• C. Compensated respiratory alkalosis
• D. Uncompensated respiratory acidosis

Answer: (A)

Interpreting ABG results starts with finding the primary disturbance and then checking for compensation. The pH is elevated at 7.51, which means alkalemia. The bicarbonate is markedly high at 38 mEq/L, pointing to a metabolic origin. The pCO2 is normal at 40 mmHg, and there is no rise in CO2 that would indicate respiratory compensation. In metabolic alkalosis, the body would compensate by hypoventilating to increase pCO2 toward roughly 50 mmHg; the observed pCO2 staying at 40 shows no such adjustment. Therefore, this pattern fits uncompensated metabolic alkalosis.

Interpreting ABG results starts with finding the primary disturbance and then checking for compensation. The pH is elevated at 7.51, which means alkalemia. The bicarbonate is markedly high at 38 mEq/L, pointing to a metabolic origin. The pCO2 is normal at 40 mmHg, and there is no rise in CO2 that would indicate respiratory compensation. In metabolic alkalosis, the body would compensate by hypoventilating to increase pCO2 toward roughly 50 mmHg; the observed pCO2 staying at 40 shows no such adjustment. Therefore, this pattern fits uncompensated metabolic alkalosis.