Pulmonary function tests are a group of tests that measure how well the lungs take in and release air. These tests determine how much air an individual’s lungs can hold, how quickly they can move air in and out and how well their lungs put in oxygen and remove carbon dioxide from the blood. All people who currently smoke and former smokers can benefit from these tests as well as patients with asthma, COPD, congestive heart failure, cystic fibrosis and others.
Benefits of pulmonary function tests
• Diagnose certain types of lung disease including asthma, chronic bronchitis and emphysema
• Determine degree and nature of the impairment
• Determine if medications are effectively treating an individual’s lung disease
• Measure disease progression
• Measure perioperative pulmonary risk prior to undergoing surgery
• To characterize impairment as restrictive, obstructive or mixed:
Restrictive Lung Diseases – Restrictive lung diseases include conditions which hinder a person’s ability to fully expand their lungs. A few examples of restrictive lung disease include:
o Interstitial lung disease, sarcoidosis, pulmonary fibrosis, neuromuscular disease such as amyotrophic lateral sclerosis (ALS or Lou Gehrig’s disease) and scoliosis.
Obstructive Lung Diseases – Obstructive lung diseases, on the other hand, include conditions that make it hard for individuals to exhale all the air from their lungs. Some obstructive lung conditions include:
o Chronic obstructive pulmonary disease (COPD), asthma, bronchiectasis and cystic fibrosis.
Who needs a pulmonary function test
There are a few reasons why someone would need a pulmonary function test. Signs that a test is necessary include: increased breathing rate, shortness of breath, drowsiness, headaches, dizziness, fainting, hot and cold flashes, tunnel or blurry vision, or decrease in judgement or coordination.
What happens during a pulmonary function test
• Spirometry – This test begins with the patient breathing forcefully into a tube which determines lung function and allows a computer to recognize signs of asthma and other pulmonary conditions.
• Body Plethysmography – This test calculates how much air is inside an individual’s lungs when they fully breath in and out.
• Methacholine challenge – This test is used to rule out asthma. Patients are given medicine they inhale which causes mild lung constriction. If the patient does not have any symptoms they can likely rule out asthma.
• Lung Diffusion Capacity – This test determines how effectively oxygen moves from the lungs into the blood stream.
• Exhaled nitric oxide – The patient gently breathes into a machine that measures the amount of allergic inflammation in the lungs. For patients with asthma, this test can help determine if certain types of medications can work effectively.
What to do before a pulmonary function test
1. Ask the healthcare provider if bronchodilators and inhaler medications should be stopped prior to the test.
2. Semi-fast. Do not eat a heavy meal before the test.
3. Do not smoke for at least 4 hours before the test.
4. Wear loose and lightweight clothing.
5. Patient should be rested with minimal exertion or excitement prior to testing.
6. Follow any other instructions from the healthcare provider.
What to do if you have lung disease
Lung diseases are generally diagnosed after a pulmonary function test or other physical exams performed by specialized pulmonary physicians. The sooner the issue is identified the sooner individuals can get on the road to recovery. Accurate diagnosis and measurements of airflow obstruction can lead to successful treatment while simultaneously lowering the risk of stroke, heart attack and lung cancer.
OakBend Medical Center is proud to provide a full range of pulmonary and critical care services in Houston. To schedule a pulmonary function test or to have any questions answered by a skilled lung disease specialist please call 281-341-3000.