<prompt> When evaluating an ABG from a client with a subdural hematoma, the nurse notes the PaCO2 is 30 mm Hg. Which of the following responses best describes this result?Appropriate; lowering carbon dioxide CO2 reduces intracranial pressure ICP.Emergent; the client is poorly oxygenated.NormalSignificant; the client has alveolar hypoventilation.  <response>: A normal PaCO2 value is 35 to 45 mm Hg. CO2 has vasodilating properties; therefore, lowering PaCO2 through hyperventilation will lower ICP caused by dilated cerebral vessels.Option B: Oxygenation is evaluated through PaO2 and oxygen saturation.Option D: Alveolar hypoventilation would be reflected in an increased PaCO2. 