DIFFUSION STUDIES

Pulmonary Function Tests: Spirometry | Body Plethysmography | Diffusion Studies


Image by Joe Mabel, CC BY-SA 3.0, Link

Diffusion tests find out how well the oxygen in the air you breathe into your lungs moves from your lungs into your blood.

This test is done by having you breathe into a mouthpiece connected to a machine. You will be asked to empty your lungs by gently breathing out as much air as you can. Then you will breathe in a quick but deep breath, hold your breath for 10 seconds, and then breathe out as instructed.

It usually takes about 15 minutes to complete this test.

What should I know before doing a diffusion test?

  • Do not smoke and stay away from others who are smoking on the day of the test.
  • If you are on oxygen, you will usually be asked to be off oxygen for a few minutes before taking this test.