Are you suffering from shortness of breath, coughing, or wheezing? Do you constantly use tobacco products? Are you considering lung or airway surgery for your pulmonary condition? You might be interested in pulmonary function tests to assess your lung function.

Pulmonary function testing is a non-invasive diagnostic test used to determine how well the lungs function at rest and during a physical activity such as exercise.

Let’s explore the types of pulmonary function testing, what they measure, and the importance of lung capacity and airflow measurement in making a pulmonary diagnosis.

Types of PFTs

The four main types of pulmonary or lung function tests are as follows:


This is one of the most popular PFTs that estimate how much air is in your lungs. The test measures how much air you can take and breathe out.

Body Plethysmography

This PFT measures the various amounts of air in the lungs after different points of inhalation and exhalation.

Gas Diffusion Study

The gas diffusion study measures how much oxygen and other gases are diffused from the lungs to your blood.

Cardiopulmonary Exercise Test

This type of PFT measures how well your heart muscles and lungs work during exercise.

Using these PFTs, a pulmonologist can measure the following.

  • Tidal volume. The amount of air that is inhaled or exhaled during normal breathing.
  • Minute volume. This refers to the total amount of air exhaled from the lungs per minute.
  • Vital capacity. This is the total volume of air that can be breathed out after inhaling as much as an individual can.
  • Residual volume. This is the amount of air left in the lungs after exhaling as much as an individual can.
  • Functional residual capacity. This refers to the amount of air that is left in the lungs after exhaling normally.
  • Total lung capacity. This refers to the total volume of the lungs when filled with air as much as possible.
  • Forced vital capacity. This refers to the amount of air that a person exhales forcefully and quickly after inhaling as much as they can.
  • Forced expiratory volume. The amount of air that expires during the first, second, and third seconds of the forced vital capacity test.
  • Forced expiratory flow. This is the average rate of flow during the middle half of the forced vital capacity test.
  • Peak expiratory flow. This refers to the fastest rate at which you can exhale air.

Importance of Lung Capacity and Airflow Measurement

Lung capacity is the total amount of air that the lungs can hold. Forced vital capacity, forced expiratory volume, total lung capacity, and residual volume help measure the lung capacity of an individual during pulmonary function tests, such as spirometry. On the other hand, forced expiratory flow and peak expiratory flow help assess the airflow in the lungs.

pulmonary specialist compares a patient’s pulmonary function test results with those of a person of similar age, sex, height, and race. Typically, a lower lung capacity and airflow indicate health conditions like chronic lung disease, such as COPD, asthma, emphysema, and other health conditions, that prevent lungs from functioning properly. PFT results not only help make a diagnosis of respiratory conditions but also show how well treatments are working to manage the symptoms associated with a respiratory condition.

Pulmonologist in North Texas

If you think you or someone close to you is suffering from a pulmonary problem, don’t delay; contact our highly qualified and experienced pulmonologist here at  Lung & Sleep Specialists of North Texas. Our pulmonologist, Dr. Olusegun Oseni, MD, FCCP, DABSM, uses state-of-the-art diagnostic testing methods like PFTs to give our patients an accurate diagnosis and effective treatment plan. We also use cutting-edge tools and equipment to monitor the recovery of lungs after an illness.

If you want a comprehensive evaluation and would like to discuss the treatment options for your unique pulmonary disorder, arrange a consultation with us today by calling (817) 594-9993 or using our online appointment request form.

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