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 Pulmonary Function Test



Pulmonary Function Test

Pulmonary function tests (PFTs) are a group of tests that evaluates how well the lungs are functioning. This includes assessing your breathing and how effective the lungs are  to bring oxygen to the rest of your body.

Your doctor may order these tests:

  • To evaluate  problems like shortness of breath or chronic cough or labored breathing
  • To screen for obstructive or restrictive lung diseases such as asthma or chronic obstructive pulmonary disease (COPD)
  • To document the progression of lung diseases - restrictive or obstructive
  • To assess lung functions before surgery
  • To document the effectiveness of therapeutic intervention

The following diseases can be diagnosed and evaluated with the help of  a pulmonary function test:

  • Asthma
  • COPD- emphysema or chronic bronchitis
  • Allergies
  • Lung fibrosis
  • Bronchiectasis
  • Asbestosis, a condition caused by exposure to asbestos
  • Sarcoidosis, an inflammation of your lungs, liver, lymph nodes, eyes, skin, or other tissues
  • Scleroderma, a  connective tissue disorder that can affect the lungs
  • Tumor of pulmonary origin
  • Weaknesses of the chest wall muscles

How to prepare for a pulmonary function test

Avoid caffeinated foods or drinks and heavy meal just before the test. Don't smoke or exercise strenuously at least for six hours before the test. Wear loose clothing that won't restrict your breathing, and wear dentures to the testing if you normally wear them. The day of the PFT, bring with you any breathing medicine that you take.  You may need your quick-relief inhaler during or after the test. The PFT will take 45 minutes to 1 hour to complete.

During the Test

Tell your test conductor right away if you feel any of the following:

  • Are dizzy or become light-headed
  • Have chest pain
  • Have shortness of breath
  • Feel nervous or feel that your heart is racing