A client with a bowel obstruction is experiencing intractable vomiting for the last several hours despite the administration of prescribed antiemetics. The nurse obtains the client's arterial blood gas (ABG) results which identify a pH of 7.50, a PaCO2 of 42 mm Hg, and an HCO3 of 33 me/L (33 mmol/L). The nurse should interpret these results as confirming which acid-base imbalance?

Choice A reason: Respiratory acidosis is characterized by a low pH and an elevated PaCO2 due to hypoventilation, which results in CO2 retention. The ABG results in this case show a normal PaCO2, making this option incorrect.Choice B reason: Metabolic acidosis is characterized by a low pH and a low HCO3 due to an accumulation of acids or loss of bicarbonate. The ABG results show a high pH and a high HCO3, which are opposite to the findings of metabolic acidosis.Choice C reason: Metabolic alkalosis is characterized by a high pH and an elevated HCO3. This condition can result from excessive loss of stomach acid due to vomiting or the use of diuretics. The ABG results show a pH of 7.50 and HCO3 of 33 me/L, both indicative of metabolic alkalosis.Choice D reason: Respiratory alkalosis is characterized by a high pH and a low PaCO2 due to hyperventilation, which leads to CO2 loss. The ABG results show a normal PaCO2, ruling out respiratory alkalosis as the correct diagnosis.