Pulmonary Function Testing

Introduction

Do you want to know how well your lungs are working? Then pulmonary function testing (PFT) is the test that can help you figure it out. Lung volume, airflow, and gas exchange are some of the things that this test looks at. This full checkup of your lungs helps doctors diagnose lung conditions, keep an eye on long-term illnesses, and decide how to treat you. Using PFTs, doctors can learn a lot about your lung health and treat you in a way that fits your needs.

What Is Pulmonary Function Testing (PFT)?

Pulmonary Function Tests show how well your lungs are working. With this test, a medical professional can get information about lung volume, capacity, rate of flow and gas exchange. Using PFT test results along with patient history, and physical examination the severity of pulmonary impairment can be easily detected. It does not only act as a test for diagnosis but also to monitor chronic diseases like asthma, lung diseases, and more.

Types Of Pulmonary Function Tests (PFT) And How It is Done?

The PFT consists of several tests to collect enough data to examine the overall working of the lungs. Here is the list of tests that you will have to go through

Spirometry

It helps to measure how much air a person can breathe in into their lungs, how much they can breathe out and how quickly they can do it. The simple steps that will be followed during the process of spirometry test are,

• At the special lung function lab, a soft clip will be placed on your nose allowing you to breathe only through the mouthpiece attached to the spirometer.
• You will take a deep breath in and blow it out forcefully, to measure the amount of air you blow out and inhale into your lungs.
• This will be repeated about three times to make sure the results are accurate and reproducible.
• Sometimes, you will be asked to breathe in medicine that helps in opening up the airways. And then the test is done again to find changes before and after including the medicine.

Lung Volume Tests

During a lung volume test, you will be asked to breathe a special mixture of gases inside an airtight room with a soft clip on your nose. Inside this room the air pressure changes, which helps in finding the amount of air your lungs can hold, and how much stays in the lungs after you breathe out. 

Diffusion Capacity Test (DLCO)

The Diffusion Capacity Test (DLCO) checks how well your lungs transfer gases into your bloodstream. During the test, you breathe in a small amount of carbon monoxide, and the test measures how effectively it’s absorbed into your blood. It helps doctors understand how well your lungs are functioning and can be useful in diagnosing and tracking lung diseases.

Peak Expiratory Flow (PEF)

You can find out how fast you can breathe out with the Peak Expiratory Flow (PEF) test. You use a peak flow meter to measure how hard and fast you can blow out your breath after taking a deep breath. The result tells you how well your airways are working and helps doctors keep an eye on conditions like asthma by keeping track of how your airflow changes over time.

Exercise Tests

Exercise tests check how well your heart and lungs work when you’re moving around. In most cases, they involve:

• The Cardiopulmonary Exercise Test (CPET) checks how well your heart and lungs work while you exercise by checking how well your body uses oxygen and gets rid of carbon dioxide.
• The treadmill stress test checks your heart’s response to increasing levels of exercise on a treadmill. This can help doctors figure out what’s wrong with your heart and check your overall cardiovascular health.
• The six-minute walk test (6MWT) checks your endurance and overall fitness by seeing how far you can walk in six minutes.

These tests help doctors figure out what’s wrong with a person’s heart or lungs, see how much exercise they can handle, and see how well their treatments are working.

Cardiopulmonary Exercise Test (CPET)

When you work out, the Cardiopulmonary Exercise Test (CPET) checks how well your heart and lungs work together. While you work out on a treadmill or stationary bike, monitoring equipment keeps track of your breathing, heart rate, and oxygen use. This test helps doctors figure out how fit your heart and lungs are, figure out if you can’t handle exercise, and check for conditions like heart and lung diseases.

When To Take PFT?

If you have problems with your lungs or airways, like a cough that won’t go away or shortness of breath, your doctor may suggest pulmonary function tests. These tests may also be suggested if you smoke or are getting ready for surgery. Some common signs that could lead to these tests are

• Pain, pressure, or tightness in the chest
• Coughing that won’t go away, especially with mucus or phlegm
• Having trouble breathing deeply
• Being unable to breathe
• Wheezing

Your doctor may do these tests as part of a regular check-up, even if you don’t have any symptoms. This is what pulmonary function tests can do for your doctor:

• Spot narrowing in your airways
• Detect early signs of how well your lungs are transferring oxygen to your blood
• Assess the impact of smoking on chronic lung conditions
• Determine if medication could improve your breathing
• See if exposure to environmental factors has affected your lungs
• Evaluate how well you might handle surgery or other medical procedures

Why Is PFT Performed?

• To diagnose lung conditions, such as asthma, chronic obstructive pulmonary disease (COPD), or pulmonary fibrosis.
• Check for Symptoms: If you have shortness of breath, a cough that won’t go away, or wheezing, a PFT can help find out if the symptoms are related to lung problems.
• Monitor Disease Progression: Over time, they keep track of how well your lung condition is getting worse or how well it is responding to treatment.
• Check How Well the Treatment Is Working: PFTs can tell you if your medicines or treatments are making your lung function better.
• Assessment Before Surgery: PFTs help doctors figure out if your lungs are healthy enough for certain surgeries before they happen.
• Check the Effects of Smoking or Exposure: This is where they look at how smoking or being exposed to harmful substances has changed your lung health.
• Check for Early Changes: PFTs can find small changes in lung function before they become more obvious.

Are There Any Risks in PFT?

Pulmonary function testing is generally safe. However, you might feel dizzy, lightheaded, or fatigued from deep breathing during the test. Blowing into the mouthpiece could also cause some coughing, and exercise may leave you feeling tired. These effects should subside shortly after the test is completed. If you need a break during the procedure, let your healthcare provider know.

In very rare cases, a pulmonary function test might lead to a collapsed lung (pneumothorax). Additionally, the test can temporarily increase your heart rate. Make sure to inform your healthcare provider if you’ve recently had a heart attack or have any other heart conditions.

Conclusion

Pulmonary function testing is a useful way to check the health of your lungs and find out what’s wrong with your breathing. By checking different parts of lung function, these tests tell you a lot about how well your lungs are working and help you see how long-term illnesses last. PFTs give you important information that can help guide your treatment and make sure you have the best lung health, whether you are dealing with symptoms or getting ready for surgery. Talk to your doctor or nurse about your results and what to do next at all times.