Pulmonary Diffusing Capacity: Health (PK4)

Question 1

What is pulmonary diffusing capacity?

Answer 1

Ability to diffuse gases across the lungs

Question 2

What is flow (V̇) of a gas across a diffusion barrier proportional to?

Answer 2

• Diffusibility of gas
• Area
• 1/Thickness
• Difference in pressures

Question 3

Equation linking flow (V̇), diffusibility (d), area (A), 1/thickness (1/T) and difference in pressure (P1-P2)

Answer 3

V̇ = d x (A/T) x (P1-P2)