From the Guidelines
A Pulmonary Function Test (PFT) is a group of breathing tests that measure how well your lungs are working, including lung volume, capacity, rates of flow, and gas exchange, providing important information about lung function and helping diagnose conditions like asthma, chronic obstructive pulmonary disease (COPD), and pulmonary fibrosis. The most common PFT is spirometry, which measures how much and how quickly you can move air in and out of your lungs, as noted in the American Thoracic Society/European Respiratory Society statement 1. Other tests include lung volume measurement, diffusion capacity testing, and exercise stress testing.
According to the American Society of Hematology 2019 guidelines for sickle cell disease, PFTs are useful diagnostic tools for individuals with signs and symptoms suggestive of chronic respiratory impairment 1. However, the utility of PFT as a screening tool for asymptomatic individuals with sickle cell disease is not clear.
The tests are non-invasive and usually take 30-90 minutes depending on which tests are performed. You should avoid smoking, heavy meals, and strenuous exercise before the test, and inform your doctor about any medications you're taking as some may need to be temporarily stopped. PFTs are valuable diagnostic tools that help healthcare providers determine appropriate treatment plans for respiratory conditions, as also suggested by the European Respiratory Society task force on chronic obstructive pulmonary disease 1.
Some key aspects of PFTs include:
- Spirometry: measures how much and how quickly you can move air in and out of your lungs
- Lung volume measurement: measures the amount of air in your lungs
- Diffusion capacity testing: measures how well oxygen moves from your lungs into your blood
- Exercise stress testing: measures how well your lungs function during physical activity
Overall, PFTs are essential diagnostic tools for assessing lung function and guiding treatment plans for various respiratory conditions, as supported by the most recent guidelines and studies 1.
From the Research
Definition and Purpose of Pulmonary Function Tests (PFTs)
- Pulmonary function tests (PFTs) provide quantitative information about lung function to diagnose and manage respiratory diseases 2, 3.
- PFTs are used to assess the severity and course of disease, evaluate patients for lung transplantation, and monitor response to treatment 2, 4.
Components and Measurements of PFTs
- The key components of PFT panels include static lung volumes, dynamic lung function (spirometry), and diffusion capacity 2.
- PFTs measure various parameters, such as forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and carbon monoxide diffusion capacity (DLCO) 5, 6.
Interpretation and Clinical Implications of PFTs
- The interpretation of PFTs requires knowledge of respiratory physiology and involves comparing results to those of a healthy reference population 3, 5.
- PFTs can help identify ventilatory impairments, such as obstructive or restrictive patterns, and assess the severity of disease 5.
- PFT results can guide clinical decision-making, including diagnosis, treatment, and monitoring of respiratory diseases 2, 6.