A client is admitted to the emergency room with a respiratory rate of 7/min. Arterial blood gases (ABG) reveal the following values. Which of the following is an appropriate analysis of the ABGs? pH 7.22 PaCO2 68 mm Hg Base excess-2 PaO2 78 mm Hg Saturation 80% Bicarbonate 26 mEq/L

Rationale: A. Metabolic acidosis would present with a low pH and low HCO₃⁻. Here HCO₃⁻ is near normal (26 mEq/L), so a primary metabolic disorder is unlikely. The elevated PaCO₂ explains the acidemia. B. Respiratory alkalosis produces an increased pH and decreased PaCO₂. This ABG shows a low pH and markedly elevated PaCO₂ (68 mm Hg), so it is not respiratory alkalosis. C. The low pH (7.22) with a markedly elevated PaCO₂ (68 mm Hg) indicates primary respiratory acidosis due to hypoventilation (consistent with RR 7/min). The bicarbonate (26 mEq/L) is near normal, suggesting an acute respiratory acidosis with little metabolic compensation. The low PaO₂ and low saturation indicate significant hypoxemia as well. D. Metabolic alkalosis would show an elevated pH with an elevated HCO₃⁻. This ABG demonstrates acidemia with normal HCO₃⁻ and high PaCO₂, so metabolic alkalosis is not the cause.