Pulmonary Function Testing- Allergy/Immunology, Diagnostics, Pulmonary And Respiratory Medicine

Doctors: Pulmonologist, Chest Physician

What are pulmonary function tests (PFTs)?

PFTs are non-invasive tests to determine the function of the lungs. These tests measure lung volume, capacity, rates of flow, and gas exchange.

Who requires PFTs?

PFTs can be done as a routine physical check-up in healthy individuals. These tests help to diagnose various conditions such as allergies, asthma, COPD, emphysema, chronic bronchitis, respiratory infections, asbestosis, sarcoidosis, scleroderma, restrictive airway problems etc.

Pulmonary function tests:

There are various types of PFTs as mentioned below:

  • Spirometry: This test helps to measure the rate of air flow and estimates lung size. During this test, the patient is asked to breathe multiple times, with regular and maximal effort, through a tube that is connected to a computer.
  • Lung volume test: It is the most precise way to measure the volume of air a patient’s lungs can hold. The procedure is similar to spirometry, except that the patient will be in a small room with clear walls or a glass chamber.
  • Lung diffusion capacity: This test evaluates how well oxygen gets into the blood from the air during breathing process. During this test, the patient is asked to breathe in and out through a tube for several minutes without having to breathe intensely. Patient may be asked to provide blood sample for the measurement of hemoglobin levels.
  • Pulse oximetry: This test estimates oxygen levels in blood. During this test, a probe is kept on patient’s finger.
  • Arterial blood gas test: This test measures the levels of gases, such as oxygen and carbon dioxide, in blood. During this test, blood sample is taken from an artery.
  • Fractional exhaled nitric oxide test: This test measure how much nitric oxide is in the air that patient exhales. During this test, the patient is asked to breathe out into a tube that is connected to the portable device. It requires steady but not intense breathing.



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About the Author:

Dr. Anand Lakhkar is a physician scientist from India. He completed his basic medical education from India and his postgraduate training in pharmacology from the United States. He has a MS degree in pharmacology from New York Medical College, a MS degree in Cancer/Neuro Pharmacology from Georgetown University and a PhD in Pharmacology from New York Medical College where he was the recipient of the Graduate Faculty Council Award for academic and research excellence.  His research area of expertise is in pulmonary hypertension, traumatic brain injury and cardiovascular pharmacology.  He has multiple publications in international peer-reviewed journals and has presented his research at at prestigious conferences.