Interpretation of ABG: pH 7.51, PCO2 44, HCO3 36; the primary problem is...

Interpretation of ABG: pH 7.51, PCO2 44, HCO3 36; the primary problem is...

• A. Respiratory
• B. Metabolic
• C. Mixed metabolic and respiratory
• D. No disturbance

Answer: (B)

Alkalemia is indicated by the pH of 7.51. The primary abnormal value is the bicarbonate, which is elevated at 36 mEq/L. A high HCO3- with an alkaline pH points to a metabolic alkalosis as the primary problem. The PCO2 is 44 mmHg, which is within the normal range and does not by itself explain the alkalemia; in metabolic alkalosis the body typically compensates with a rise in PCO2 (hypoventilation), but the compensation is not required to identify the primary defect. So, the elevated bicarbonate driving the alkaline pH makes the metabolic disturbance the main issue.

Alkalemia is indicated by the pH of 7.51. The primary abnormal value is the bicarbonate, which is elevated at 36 mEq/L. A high HCO3- with an alkaline pH points to a metabolic alkalosis as the primary problem. The PCO2 is 44 mmHg, which is within the normal range and does not by itself explain the alkalemia; in metabolic alkalosis the body typically compensates with a rise in PCO2 (hypoventilation), but the compensation is not required to identify the primary defect. So, the elevated bicarbonate driving the alkaline pH makes the metabolic disturbance the main issue.