clinical definition of spirometry
A spirometry test is the most popularly used pulmonary function test (PFT). It is a common office test used to assess how well your lungs work by measuring how much air you inhale, how much you exhale and how quickly you exhale. Spirometry is used to diagnose asthma, chronic obstructive pulmonary disease (COPD) and other conditions that affect breathing.
what is a spirometry test?
The Spirometry test is a pulmonary function test, which means that it tests the functioning of the lungs. The aim of the test is to check how well the lungs of the patient are functioning. This is done by measuring the amount of air which flows in and out of the lungs of the patient.
The patient will be made to sit in a spot and blow into a device called the spirometer. This device will record the amount of air which you blow in and out, and also the speed with which you breathe in and out. The test is done to check if the patient has any lung diseases or disorders, like COPD, asthma, restrictive lung disease or any type of lung disorders.
The doctor will also be able to monitor the progress of any chronic lung diseases, and see how far your breathing has progressed. The spirometry test is one of the many pulmonary function tests.
how is spirometry test done?
The spirometry test only takes about 15 minutes to do, and will usually happen right in the doctor’s office. You will be made to sit in a chair, and a clip will be placed on your nostrils so that no air flows through them.
The nurse will then place a cup-like mask over your mouth and nose, through which you can breathe. You will then be asked to breathe in deeply, and hold your breath for some time. After that, you will have to exhale as hard as you can into the mask itself.
The procedure will be repeated at least three times so that no errors occur in the results. The highest value of the three close results will be treated as the final result of the test.
If you have any existing pulmonary disorder, then the doctor will give you a bronchodilator, which is a medicine which helps open the airway after the first round of the test. After waiting for around 15 more minutes, the test will be repeated again.
By comparing the results of the second test to the first, the doctor will be able to conclude whether the inhaled medicine is able to help you breathe better.
when do you expect results?
The spirometry test results can be expected within a few minutes of the test being completed.
why get tested?
A Spirometry test can be used for multiple purposes such as:
• To screen persons at risk for pulmonary diseases such as smokers or people in occupations with exposure to hazardous substances
• Screening for the existence of any lung diseases
• Determining the patient's condition pre and post a surgery
• Evaluate the progress of a lung disease and effectiveness of treatment
If the pulmonary test is carried out to check for any breathing disorders, it is required only once a year or once every two years. If the patient has any severe breathing problems, it is important to take this test more frequently to ascertain the condition of the lungs.
The spirometry test is extremely important if you have conditions like COPD, which is Chronic Obstructive Pulmonary Disease. The test results will be factored in by the doctor when he draws up a treatment for your condition, therefore it is important to check the health of your lungs frequently.
Other factors considered by your doctors will include heart disease, exercise capabilities and your physical conditions. Using the results of the test, he might also prescribe surgery or further medicines to help alleviate your condition.
Another important function of the test is that it help the doctor understand at a deeper level whether the medication and the rehabilitation program is progressing well. If the results point to the fact that the lung capacity is stable, then the doctor will be able to alter the medication to the required level.
Spirometry test is a simple, non-invasive test which can therefore help your doctor understand a lot about the condition of your lungs. The test results can help him treat a host of conditions, like COPD, asthma and fibrosis in the lungs. Many other diseases which affect the lungs are also treated only after the spirometry test is conducted.
reason to take spirometry test
• Difficulty in breathing
• A cough
• Chest pain
• Expiratory slowing
• Wheezing
• Chest deformity
• Cyanosis
• Diminished breath sounds
• Phlegm or bulgum production
preparations needed for spirometry test
Preparatory instructions before the test *: The patient should not have a heavy meal right before the test is done. Also, smoking is a strict no for at least 4-6 hours before the test.
Alcohol should also be avoided on the day of the test, along with smoking- this is because all three of the above actions may impair your ability to breathe freely. The patient should be wearing loose, non-restrictive clothing so that he feels no difficulty in breathing properly.
If you take any medication which has to be inhaled, you should tell your doctor about it- he may tell you to avoid it on the day of the test.
sample required?
Diagnostic procedure: Soft nose clips can be used during the test to prevent any air escaping through the nose. The patient should breathe in fully to take in maximum air possible. Exhale with force for six seconds into a tube-like a device linked to the spirometer.
Results are recorded. Test readings are generally taken three times to eliminate errors.
does spirometry test pose any risk?
The pulmonary spirometry test is not usually harmful to the patient, although a shortness of breath and dizziness is common right after the test is completed. Severe breathing problems are triggered in the patient in very rare cases.
However, since the test can be a tiring process, it is not recommended for patients who have serious cardiac conditions or has any type of heart issues.
how do you understand spirometry test result?
The test results are not exactly the same for two people since they depend upon various factors like the age and the physical features of the person. Your doctor will be able to calculate a value based on your features, and the test results will be compared to the predicted value to check how well your lungs are functioning.
If the score you get from the test is 80% or more of the predicted value, your results are considered to be normal.
If the results are found to be abnormal, then the doctor will prescribe further tests in order to diagnose your condition. These may include X-rays of the chest or even blood tests. Conditions like heartburn, hay fever and sinusitis may make your breathing disorders worse, so the doctors will be sure to prescribe medicines for those conditions.
Understanding results ofSpirometry
Reference Range | Interpretation |
---|---|
Pulmonary diseases Obstructive small airway diseases Interstitial lung diseases Cardiac diseases Congestive heart failure Neuromuscular diseases Guillain-Barré syndrome |
‘*A Reference range is a set of values which helps the healthcare professional to interpret a medical test. It may vary with age, gender, and other factors. Reference ranges may also vary between labs, in value & units depending on instruments used and method of establishment of reference ranges’.
References
- https://www.nationaljewish.org/treatment-programs/tests-procedures/pulmonary-physiology/pulmonary-function/spirometry
- https://familydoctor.org/chronic-obstructive-pulmonary-disease-copd-spirometry/
- https://getasthmahelp.org/pft.aspx
- https://foundation.chestnet.org/patient-education-resources/lung-function-tests/
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5392482/