Question

Coal miners who spend years inhaling fine coal dust have much of their alveolar surface covered with scar-like tissue. How would this condition affect exchange of gases between alveoli and capillaries? Explain in details.

Answer 1

• Compliance of lungs is based on elasticity and surface tension of the lungs. Compliance and elastic recoil are inversely related to each other. When lung tissue gets swelled and thickens, the lung compliance decreases.
• An increase in surface tension is associated with a decrease in compliance. Therefore, surfactants (secreted by type II epithelial cells) are helpful in overcoming compliance.
• With the lungs with low level of compliance, the lungs seem to be stiff. It becomes tough to breath with the stiff lungs.
• The pulmonary fibrosis and scar formation due to coal dust makes it difficult to expand and relax the lungs which makes breathing complicated and troublesome.