Breathing is something most of us take for granted. But when breathing becomes a struggle, it’s essential to find out why. That’s where a Pulmonary Function Test (PFT) comes in. PFTs are a group of non-invasive tests that measure how well your lungs are working. They evaluate how much air your lungs can hold, how quickly you can move air in and out, and how well your lungs deliver oxygen to your blood.
Doctors often recommend PFTs for people who experience breathing problems, such as asthma, chronic cough, shortness of breath, or conditions like COPD (Chronic Obstructive Pulmonary Disease). They are also useful for monitoring lung health if you’re on certain medications or if you have been exposed to harmful substances.
What to avoid before a pulmonary function test
Preparing for a pulmonary function test is crucial for accurate results. Here are some important things to avoid before your test:
Smoking
Don’t smoke for at least 4-6 hours before the test. Smoking can affect lung function and distort the results.
Eating large meals
Avoid heavy meals within 2 hours of the test. A full stomach can restrict lung expansion, making it harder to breathe deeply.
Using certain medications
Some medications, especially those used to treat respiratory conditions, may need to be paused before the test. Always consult your doctor about what medications to avoid.
Strenuous exercise
Try to avoid heavy physical activity before the test, as it can alter your breathing patterns.
How long does a pulmonary function test take?
The duration of a pulmonary function test varies depending on the types of tests being performed. Generally, a simple spirometry test takes about 30 minutes or less. However, a complete set of tests, including lung volume measurement and gas diffusion studies, can take up to 90 minutes. Make sure to wear loose, comfortable clothing and arrive on time to avoid any unnecessary stress.
Understanding pulmonary function test results
After completing your PFT, your healthcare provider will provide a detailed report. But what do all those numbers mean?
Forced Expiratory Volume in One Second (FEV1)
This measures how much air you can forcefully exhale in one second. Lower values can indicate obstructive lung diseases like asthma or COPD.
Forced Vital Capacity (FVC)
This measures the total amount of air you can forcefully exhale after taking a deep breath. Reduced values can indicate restrictive lung diseases.
FEV1/FVC Ratio
This ratio helps differentiate between obstructive and restrictive lung diseases. A low ratio usually suggests an obstructive condition.
Diffusing Capacity of the Lungs for Carbon Monoxide (DLCO)
This assesses how well your lungs transfer oxygen to your blood. Low results can indicate issues with lung function or blood flow.
Interpreting the results accurately requires expertise, but understanding the basics can help you ask better questions when discussing your results with your doctor.
Tips for doing well on a pulmonary function test
You can’t exactly “pass” or “fail” a PFT since it’s not a test of performance but of function. However, you can ensure accurate results by following these tips:
Follow preparation guidelines
Avoid smoking, heavy meals, and specific medications as advised by your doctor.
Stay relaxed
Being nervous can affect your breathing. Try to stay calm and breathe as normally as possible during the test.
Listen to instructions carefully
The test administrator will guide you through each step. Follow their instructions for the most accurate results.
Avoid vigorous exercise beforehand
Resting your body ensures your breathing is natural and not altered by physical activity.
Final thoughts
A pulmonary function test is an essential tool for diagnosing and monitoring lung health. Whether you’re managing a chronic condition or simply trying to understand unexplained breathing issues, PFTs provide valuable insights that can guide effective treatment plans. Remember, caring for your lungs is caring for yourself and your loved ones — and we’re here to help you every step of the way.