What is a lung function test (PFT) used for?

Lung function tests are a range of tests used to measure how well your lungs work and can help diagnose the cause of breathing problems.

These tests measure how much air your lungs can take in and how fast you can blow this out, to see whether your lung capacity is in the normal range. Lung function tests also measure how well your lungs deliver oxygen to your blood and how strong your breathing muscles are.

A range of conditions can be diagnosed using these tests including:

· Chronic obstructive pulmonary disease (COPD) – which includes a range of lung diseases that can cause breathlessness, frequent chest infections and a phlegmy cough.

· Asthma – which leads to shortness of breath and is often caused by allergies.

· Pulmonary fibrosis – where scarring of the lungs can cause shortness of breath.