Pulmonary Function Test

What is a Pulmonary Function Test (PFT)? 

A Pulmonary Function Test (PFT) is a crucial diagnostic tool for evaluating lung function in children, especially those diagnosed with chronic pulmonary conditions such as cystic fibrosis or bronchopulmonary dysplasia. Conducting a PFT allows pediatricians to assess changes in pulmonary health over time. If your child is over the age of 5, they can typically perform the necessary breathing maneuvers for PFT testing.

Pulmonary Function Tests include various assessments:

  • Total Lung Capacity (TLC) Test: Measures the amount of air your child's lungs can hold. This involves placing your child in a clear Plexiglas booth called a 'plethysmograph' or "the box."
  • Spirometry Test: Measures the volume of air your child can exhale after taking the largest possible breath. It also assesses the speed at which air is expelled, known as 'flow speed.'
  • Oxygen Saturation: Measures the levels of oxygen and carbon dioxide in your child's blood using a non-invasive method with a small red light on their fingernail.
  • Arterial Blood Gas Test: Involves a blood test, drawing blood from your child's wrist, to provide detailed information about oxygen and carbon dioxide levels, offering insight into lung function.


Additionally, your child's pediatrician may conduct tests to:

  • Determine respiratory muscle strength.
  • Evaluate responsiveness to medications.
  • Measure lung responsiveness to exercise and cold air.

Preparing Your Child for a PFT:

Before the test, ensure your child doesn't consume solids for 6 hours and liquids for 4 hours. Although the test is not discomforting, it requires relaxation as your child breathes into a mask. A mild sedative may be administered to allow them to sleep through the procedure, typically lasting around 50 minutes.

After a PFT:

Post-test, your child may be thirsty and will be allowed to drink once they can do so comfortably. Expect some coordination issues for the day, and your child may feel tired and want to nap. Normal activities should resume by the evening. Parents will receive discharge care instructions and a contact number for any queries. Results are typically available within a week.

We ensure your child receives exceptional care at any of SuraMed Health Center pediatrician offices in West Palm Beach, Wellington, Greenacres, Boca Raton and Port St. Lucie. If you have concerns about your child's health or wish to schedule an appointment to discuss pulmonary function tests, please contact us.