When evaluating an arterial blood gas from a male client with a subdural hematoma, the nurse notes the Paco2 is 30 mm Hg. Which of the following responses best describes the result?
A. Appropriate; lowering carbon dioxide (CO2) reduces intracranial pressure (ICP).
B. Emergent; the client is poorly oxygenated.
C. Normal.
D. Significant; the client has alveolar hypoventilation.
Correct Answer: A. Appropriate; lowering carbon dioxide (CO2) reduces intracranial pressure (ICP)
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 C: The normal PaCO2 level is between 35 to 45 mmHg. PaCO2 or the partial pressure of carbon dioxide is the measure of carbon dioxide within arterial or venous blood.
Option D: Alveolar hypoventilation would be reflected in an increased Paco2. Alveolar hypoventilation is defined as insufficient ventilation leading to hypercapnia, which is an increase in the partial pressure of carbon dioxide as measured by arterial blood gas analysis.