Flow-Volume Lung Function Testing

What is lung function testing?

Lung function testing is performed to check how well the lungs are working, how much air they are able to hold, the speed at which they are able to move air in and out, and how effectively they are able to take in oxygen and remove carbon dioxide. Lung function testing is helpful in that it allows your doctor to properly diagnose disease in the lungs, as well as to assess the severity of any conditions you may have, and to evaluate the success rate of treatments and medications.

How does it work?

The lung capacity test is designed to test how much air the lungs can hold, and at what rate air can move in and out of the lungs. In order to undergo the test, your doctor will ask you to breathe into a piece of equipment that is able to collect and record information. This information can then be printed onto a chart for your doctor to easily read and assess.

What does the test measure?

A flow-volume lung function test can measure a number of factors. These include:

  • Forced vital capacity (FVC) The amount of air you are able to exhale after inhaling deeply.
  • Forced expiratory volume (FEV) The amount of air you are able to exhale with force.
  • Forced expiratory flow (FEF) The airflow halfway through exhaling.
  • Peak expiratory flow (PEF) The amount of air you are able to exhale.

Why is it helpful?

Lung function tests can be used for the following reasons:

  • To diagnose asthma
  • To diagnose chronic obstructive pulmonary disease (COPD)
  • To assess a patient’s lung function before surgery is considered
  • To check if treatment for a lung condition is working effectively