A nurse is caring for a client who has chronic kidney failure. The client's ABG values are pH 7.12 (7.35 to 7.45), HCO3 20 mEq/L (21 to 28 mEq/L), PaO2 90 mm Hg (80 to 100 mm Hg), and PaCO2 40 mm Hg (35 to 45 mm Hg). Which of the following acid-base Imbalances should the nurse identify?

A. Metabolic alkalosis: In metabolic alkalosis, the pH is elevated (above 7.45), and the bicarbonate (HCO3) is increased (above 28 mEq/L). In this scenario, the pH is low (7.12), and HCO3 is low (20 mEq/L), which is not consistent with alkalosis. B. Metabolic acidosis: In metabolic acidosis, the pH is low (below 7.35), and the bicarbonate (HCO3) is low (below 21 mEq/L), which is consistent with the client's ABG values (pH 7.12, HCO3 20 mEq/L). This suggests the client has metabolic acidosis, which is common in chronic kidney failure due to impaired excretion of acid and decreased bicarbonate. C. Respiratory acidosis: In respiratory acidosis, the pH is low, and the PaCO2 is elevated (above 45 mm Hg). The PaCO2 in this client is within the normal range (40 mm Hg), making respiratory acidosis unlikely. D. Respiratory alkalosis: In respiratory alkalosis, the pH would be high, and the PaCO2 would be low (below 35 mm Hg). The client's pH is low (7.12), and the PaCO2 is normal, so respiratory alkalosis is not present.