Final answer:
Normalizing PCO₂ in a patient having an asthma exacerbation may indicate respiratory acidosis.
Step-by-step explanation:
Normalizing PCO₂ in a patient having an asthma exacerbation may indicate respiratory acidosis. In respiratory acidosis, excess CO₂ is present in the blood which can lead to a decrease in the body's pH. Bicarbonate levels would be normal at first, but if compensation has occurred, they would decrease as the body attempts to reestablish the proper ratio of bicarbonate and carbonic acid/CO₂.