Lung Function Evaluation: What to Expect During Spirometry Testing 

Pulmonary function testing includes various breathing tests that show how well your lungs work. Specifically, they evaluate how strong your lungs are and how well they exchange air by measuring:

• How much air goes into and out of your lungs
• How much air goes from your lungs to your bloodstream
• How well your lungs work during physical exertion 

One specific test called spirometry can tell our team at Fivestar Pulmonary Associates a lot about your pulmonary health and respiratory function. Here’s why we might recommend this test for you and what you can expect along the way. 

What is a spirometry test?

As one of the most performed lung function assessments, spirometry is a simple test that gauges how much air you can breathe in and out of your lungs, as well as how easily and quickly you can blow the air out of your lungs. This noninvasive pulmonary evaluation can:

• Measure the flow of air through your lungs
• Estimate the amount of air in your lungs
• Quantify pulmonary strength and function 

We may order spirometry testing if you have symptoms like wheezing, shortness of breath, chest tightness, or a concerning cough — especially one that produces mucus. This lung function evaluation can help us diagnose or rule out lung and airway diseases like asthma, chronic obstructive pulmonary disease (COPD), and pulmonary fibrosis. 

Periodic spirometry testing is part of chronic lung disease management too. We can use it to identify early changes in lung capacity or function, see whether your condition is getting better or worse, and check the efficacy of your inhalers or medications.

Preparing for spirometry 

Accurate spirometry test results may require a bit of advanced preparation. You can take your daily medications unless instructed otherwise. Wear loose, comfortable clothing on the day of your test so you can breathe easily.

Avoid smoking for at least 24 hours prior to your appointment. For at least six hours prior to testing, refrain from using your short-acting inhaler. Within two hours of your test, don’t eat a large, heavy meal, drink alcohol, or engage in strenuous exercise. 

During your spirometry test

Done with a spirometer — a small, computerized machine connected by cable to a mouthpiece — spirometry testing is noninvasive, painless, and quick. 

Getting ready

After you’re comfortably seated, we place a soft clip over your nose to keep your nostrils closed. Next, we give you the mouthpiece that’s connected to the spirometer and show you how to close your lips tightly around it.

Three forceful blows

Once you’re ready, we ask you to take a deep breath through your mouth, wrap your lips tightly around the mouthpiece, and blow into it as forcefully as you can. We repeat the test at least three times to ensure your results are accurate and reproducible.

The machine measures the amount of air you blow out of your lungs and the amount of air you draw back in. 

Repeat testing 

In some cases, we may have you repeat the test after you breathe in a medicine that helps open your airway. This can show us if your breathing improves with medicine and help us better tailor your treatment plan. 

Potential side effects

Spirometry is a “maximal effort” test, meaning you’ll be asked to take the deepest breath you can and then blow out as hard and as fast as you can. You may feel dizzy, lightheaded, or tired right after the test, but these minor side effects should resolve quickly. 

No downtime

The average spirometry test takes 15-30 minutes to complete. Afterward, you can resume your usual activities, including exercise and medication use, without restriction. 

Spirometry testing results 

The measurements obtained from diagnostic spirometry testing are measured against numbers that are considered normal for someone of your same gender, age, and height. 

We may find that your results are normal (a predicted lung value score of 80% or greater), or we may discover indications of one or both of the following:

Obstructive lung disease

An obstructive lung problem means your ability to exhale quickly or fully is affected by a narrowing of your airways, but you can hold a normal amount of air in your lungs. Asthma, COPD, bronchiectasis, and cystic fibrosis are obstructive lung diseases. 

Restrictive lung disease

A restrictive lung problem means your air intake is restricted because you can’t fully expand your lungs. Restrictive lung diseases include pulmonary fibrosis, sarcoidosis, and interstitial lung disease; other conditions that can cause lung restriction include muscular dystrophy and scoliosis. 

Your spirometry specialists

Do you have questions about your upcoming lung function evaluation? We have answers. Call or click online to schedule a visit at your nearest Fivestar Pulmonary Associates office in Allen, McKinney, or Plano, Texas, today.