Question 4:

Erik Foran, aged 46, contracted a bacterial infection that causes the loss of type II alveolar cells. The doctor explains to his family that the subsequent collapse of the alveoli has caused a physiological shunt. 

Part A. Why does the loss of type II alveolar cells cause the collapse of alveoli and a physiological shunt? In your answer, explain what a physiological shunt is, and why it is a problem.

Part B. Erik recovers but has pulmonary fibrosis where the lung cannot expand to its full capacity. Compared to a normal FEV1/FVC ratio, what do you expect will happen to Erik’s FEV1/FVC ratio? Explain why this ratio is changed.

Part C. One of side effects of Erik’s medication is the inhibition of the carbonic anhydrase enzyme. Explain the effect of inhibiting carbonic anhydrase.