Breathing is something we take for granted—until it becomes difficult. Whether you're experiencing shortness of breath, a chronic cough, or wheezing, a lung function test can provide vital insight into your respiratory health. One of the most common and effective diagnostic tools is spirometry, but it’s just the beginning. In this blog, we explore when and why to get a lung function test, what to expect during spirometry, and how advanced pulmonary testing can help diagnose asthma, COPD, interstitial lung disease, and other serious conditions.

This detailed guide is designed to help patients, caregivers, and healthcare seekers understand the importance of pulmonary function tests (PFTs)—boosting awareness and improving health outcomes.


What Is a Lung Function Test?

Lung function tests, also known as pulmonary function tests (PFTs), are non-invasive tests that measure how well your lungs are working. They assess:

  • How much air your lungs can hold

  • How quickly you can exhale

  • How efficiently your lungs transfer oxygen into your blood

These tests help detect and monitor chronic respiratory conditions such as:

  • Asthma

  • Chronic Obstructive Pulmonary Disease (COPD)

  • Pulmonary fibrosis

  • Bronchiectasis

  • Lung damage after COVID-19

  • Occupational lung diseases


What Is Spirometry? The Gold Standard Test for Lung Health

Spirometry is the most common type of lung function test. It measures how much air you can breathe in and out, and how fast you can blow air out of your lungs.

During the test:

  • You’ll breathe into a mouthpiece connected to a spirometer.

  • You will be asked to take a deep breath and blow out as hard and fast as you can.

  • The test gives you two main results: Forced Vital Capacity (FVC) and Forced Expiratory Volume in 1 Second (FEV1).

These measurements are essential for diagnosing asthma, COPD, and restrictive lung diseases.


When Should You Get a Lung Function Test?

You should consider a lung function or spirometry test if you are experiencing any of the following:

1. Persistent Cough or Breathlessness

If you've had a chronic cough lasting more than eight weeks or if you struggle to catch your breath even after mild activity, a lung test can reveal hidden respiratory issues.

2. Wheezing or Chest Tightness

These symptoms may be linked to asthma or bronchial hyperresponsiveness. Spirometry can detect abnormal airway narrowing early.

3. Smoking History or Exposure to Air Pollution

Smokers, ex-smokers, or those exposed to airborne pollutants or dust should regularly check their lung health to screen for COPD or occupational lung diseases.

4. Monitoring Chronic Lung Conditions

If you have a diagnosed lung condition like COPD, asthma, or interstitial lung disease, regular PFTs help monitor disease progression and treatment effectiveness.

5. Pre-Surgical Evaluation

Lung function tests are often recommended before undergoing major surgery, especially heart or lung procedures, to assess your respiratory reserve.

6. Evaluation of Unexplained Fatigue or Poor Exercise Tolerance

Breathlessness and fatigue could be signs of impaired lung function. A test can help pinpoint whether your lungs are involved.


Beyond Spirometry: Other Pulmonary Function Tests

While spirometry is the most common, there are other tests that give deeper insights:

1. Plethysmography (Lung Volume Test)

Measures total lung capacity and residual volume—useful in diagnosing restrictive lung diseases.

2. Diffusing Capacity (DLCO Test)

Assesses how well your lungs transfer oxygen into your blood—important for conditions like pulmonary fibrosis or emphysema.

3. Peak Expiratory Flow (PEF)

Monitors day-to-day asthma control, especially useful for home tracking.

4. Arterial Blood Gas Analysis

Evaluates oxygen and carbon dioxide levels in your blood—crucial in advanced COPD or respiratory failure.


Benefits of Early Lung Function Testing

  • Early diagnosis of asthma, COPD, or interstitial lung diseases

  • Better management of existing lung conditions

  • Avoidance of irreversible lung damage

  • Improved quality of life through tailored treatment plans

  • Guidance for safe exercise and daily activities


Who Performs Lung Function Tests?

These tests are usually performed by respiratory therapists, pulmonologists, or trained technicians at specialized lung clinics, hospitals, or diagnostic centers.

If you are in Assam, Guwahati, or any urban center with rising air pollution and dust exposure, it is strongly advised to consult a lung specialist or chest physician for regular pulmonary check-ups.


How to Prepare for a Lung Function Test

  • Avoid heavy meals before the test.

  • Don’t smoke or use an inhaler before the test (unless instructed).

  • Wear loose clothing that won’t restrict breathing.

  • Follow specific pre-test instructions from your doctor.


Conclusion: Listen to Your Lungs—Get Tested Early

Lung function tests like spirometry are simple, safe, and essential tools to detect and manage respiratory conditions. Whether you’re experiencing symptoms or are at high risk due to lifestyle or environmental factors, don’t wait. Early testing leads to better treatment outcomes.

Take a breath, take control—your lungs deserve it.

Book your lung function test today.