Physiology

Question 1

Central chemoreceptors are most responsive to what changes in arterial conditions

Answer 1

Increase in the arterial carbon dioxide (hydrogen ions are not able to cross the BBB). Once the carbon dioxide crosses the BBB, then converted to hydrogen ions that affect the central chemoreceptors

Question 2

What are the contraindications for pulmonary function tests

Answer 2

• MI in last month
• Unstable angina
• Recent throacoabdominal or ophthalmic surgery
• THoracic or abdominal aneurysm
• Current pneumothorax