Pulm

Question 1

What is the body’s normal range for pH?

Answer 1

7.35-7.45

Question 2

At what lung volume is TPR the lowest in the pulmonary circulation? Why?

Answer 2

lowest at FRC (after tidal exhale);

• breathing out more decreases the radial stretch of incoming arteries and ↑ intrathoracic pressure
• inhaling more stretches the capillaries around alveoli

Question 3

What is the most important indicator of alveolar ventilation status? What is the nml range?

Answer 3

PaCO2: 33-45 mmHg
low = hyperventilation
high = hypoventilation