Pulmonary function tests (PFTs) are a group of breathing tests. They can show how well your lungs are working. PFTs may measure:

  • How much air you can blow out
  • How much air your lungs can hold at different times
  • How fast you are blowing air out

Respiratory System
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PFTs may be used to diagnose lung conditions or diseases, such as:

These tests may also be done to:

  • Measure how much a lung problem is affecting you
  • Evaluate symptoms such as coughing, wheezing, and trouble breathing
  • Evaluate your lung function before or after a surgery
  • Determine how well a treatment is working