Overview
Pulmonary function tests (PFTs) are noninvasive tests that show how well the lungs are functioning. The tests measure lung volume, capacity, rates of flow, and gas exchange. This information can help your healthcare provider diagnose and plan the line treatment of certain lung disorders. PFTs may be used to check lung function before surgery or other procedures in patients who have lung or heart problems, who are smokers, or who have other health conditions. Normal values for PFTs vary from person to person. The amount of air inhaled and exhaled in your test results are compared to the average for someone of the same age, height, sex, and race. Results are also compared to any of your previous test results. If you have abnormal PFT measurements or if your results have changed, you may need other tests.
Why might I need PFT?
Prevention is better than cure and early detection can be a boon to you your wellbeing. We at ACCORD Hospitals have highly skilled technicians and renowned consultants that will help perform your test seamlessly and evaluate your test results.
- Allergies
- Respiratory infections
- Trouble breathing from injury to the chest or a recent surgery
- Chronic lung conditions, such as asthma, bronchiectasis, emphysema, or chronic bronchitis
- Asbestosis, a lung disease caused by inhaling asbestos fibers
- Restrictive airway problems from scoliosis, tumors, or inflammation or scarring of the lungs
- Sarcoidosis, a disease that causes lumps of inflammatory cells around organs, such as the liver, lungs, and spleen
- Scleroderma, a disease that causes thickening and hardening of connective tissue
- Damaged or scarred lung tissue
- Weakness of the muscles in the wall of the chest
- Lung cancer
How to Prepare for a PFT
Proper preparation is crucial for getting accurate results. You will be given specific instructions, but here are some general guidelines:
- Avoid certain substances: Do not smoke or use any tobacco products for at least four hours before the test. It’s also recommended to avoid alcohol for at least eight hours and caffeine for a few hours prior.
- Discuss Medications: Tell your doctor about all the medications you are taking, especially any inhalers or other breathing medicines. You may be asked to stop taking them for a specific period (e.g., a few hours to 12 hours) before the test, as they can affect the results. Do not stop taking any medication without your doctor’s instruction.
- Don’t Eat a Heavy Meal: Avoid eating a heavy meal for at least two hours before the test. A full stomach can put pressure on your diaphragm and restrict lung expansion.
- Wear Loose Clothing: Wear comfortable, loose-fitting clothing that doesn’t restrict your breathing or chest movement.
- Avoid Exercise: Do not engage in strenuous exercise for at least 30 minutes before the test.
How it’s Done
The test is performed by a trained respiratory therapist or technician. The procedure may include several different parts.
1
Spirometry:
Sit with a nose clip, breathe deeply, and exhale forcefully into a mouthpiece, repeated several times for accuracy.
2
Lung Volumes:
Sit in a clear booth and breathe into a mouthpiece to measure total lung capacity through air pressure changes.
3
Diffusion Capacity:
Inhale a small tracer gas, hold your breath, then exhale to measure how well oxygen passes into your blood.
How it will Feel
A PFT is not painful, but it does require effort and can be physically demanding.
- Sensation – The most notable sensation is the forceful breathing required for the tests. You may feel dizzy, lightheaded, or tired from the deep, rapid breathing.
- Discomfort – The nose clips and the tight-fitting mouthpiece may feel a little uncomfortable. You might also have a coughing fit from the forceful exhalations.
- Safety – The entire procedure is performed under professional supervision, and the technician can provide breaks if you feel tired or need to rest. The temporary symptoms of dizziness or breathlessness should go away shortly after the test is completed.