Lung function testing

What is a lung functions test?

A lung functions test, otherwise known as a pulmonary function test (PFT), is a variety of non-invasive tests done to evaluate the lungs in terms of lung volume, capacity, rates of flow, and gas exchange, providing your physician with the necessary data to make a diagnosis and determine whether or not you may have a lung disorder.

Why are lung function tests necessary?

Lung function tests are often done by a lung specialist in order to make a diagnosis. Lung functions tests may also be done to determine whether or not your particular lung condition is progressing and if treatment is working. They can be used to diagnose and monitor the progression of respiratory conditions such as

  • Asthma
  • Allergies
  • Chronic bronchitis
  • Respiratory infections
  • Lung fibrosis
  • Bronchiectasis
  • COPD
  • Exposure to asbestos
  • Inflammation of your lungs
  • A pulmonary tumour or lung cancer

What does lung function testing involve?

Lung function testing includes spirometry, lung volume test, diffusing capacity test and exercise testing. Spirometry is used to screen for lung diseases that affect the lung volume; the plethysmography test measures the volume of air in the lungs, while the diffusing capacity test measures how easily oxygen enters the bloodstream. Finally, exercise testing allows Dr Mothilal to evaluate shortness of breath and its possible cause.

What can be expected during a lung functions test?

Before the test, you will be advised what medications you should stop taking as they may affect your results. You will be asked to do a few tests breathing in and out several times. These tests will be repeated to get an accurate reading. For the spirometry, you will have a mouthpiece so that a machine can measure the amount of air your breath in and out through your mouth. Your nose will be clipped for this test to prevent air from going in or out through the nose.

Next, you will sit in a small booth and breathe into a mouthpiece so that the volume of air in your lungs can be measured. Next, you will be asked to breathe in certain gases such as oxygen, helium, or carbon dioxide so that your lung specialist can see how well gases enter the bloodstream. Your pulmonologist will prepare you for what to expect before scheduling your appointment, as you may need to wear loose-fitting, comfortable clothing and athletic shoes for the exercise test. This test is done on a treadmill.

Schedule an appointment

Christiaan Barnard Memorial Hospital

Suite 1613, 16th floor, Netcare Christiaan Barnard Memorial Hospital, Cnr DF Malan Street and Rua Bartholemeu Dias Plain, Foreshore, Cape Town, 8001