Get to know spirometry, a test to determine your lung function

Measuring lung capacity is often done to see how serious or to what extent a person has suffered lung damage. Measuring this capacity is usually done using a device called a spirometry.

How does this tool work so that it can provide information about the extent of lung damage to the patient? Check out the full review below.

What is spirometry?

Source: Chest Foundation

Spirometry is one of the best pulmonary function tests and is most often used by medical teams. The instrument used to perform a spirometry test is called a spirometer. A spirometer is a machine that measures how well your lungs are functioning, records the results, and displays them in graphic form.

Spirometer is a tool that plays an important role in chronic obstructive pulmonary disease (COPD) from the time the disease is diagnosed through treatment and control. Spirometer is used when the patient complains of respiratory problems, such as coughing, excess mucus production, or to diagnose the cause of shortness of breath. It can also detect COPD, even in its earliest stages before the onset of clear COPD symptoms.

Spirometry can also help monitor the progress of other diseases related to lung function and classify them into their respective stages or stages. It also helps determine the best way to continue treatment.

Therefore, spirometry is also an important tool used to diagnose asthma, COPD, or other respiratory diseases. With this tool, the doctor can find out whether the symptoms of shortness of breath that you are suffering from are part of asthma, and determine the right treatment.

According to the Mayo Clinic, several other diseases that can be diagnosed using a spirometry test are:

• Chronic bronchitis
• Emphysema
• Pulmonary fibrosis

Examine how spirometry works

Source: Inogen

You cannot do the spirometry test yourself at home. So, you need the help of a doctor to do an examination of your lung capacity. A spirometry test kit, namely a spirometer, will measure lung function and record the results in graphical form.

This examination is carried out at the clinic or doctor's place. The doctor will guide you to run this test. For that, make sure you follow what the doctor says.

Here are the steps for doing a spirometry test:

1. Sit in the most comfortable position
2. Then, the doctor will cover your nose using a clip-like tool just above the nose
3. Take a deep breath and hold it for a few seconds
4. Blow in mouthpiece on the spirometer as strong and fast as you can.

If you have certain respiratory problems or diseases, your doctor will ask you to do two tests. However, in the second test, the doctor will give you bronchodilator drugs to help open the respiratory tract.

Later, the results of the two tests will be compared to see if the bronchodilator is working to improve your breathing, which indicates that your breathing is indeed problematic.

Are there any side effects from this tool?

As with any medical procedure, a spirometry test can have side effects. However, there's no need to worry. The side effects of this test are generally mild and harmless. You may experience dizziness and a little shortness of breath after taking the test. This condition will usually get better soon.

In order for the test to show optimal results, it is recommended that you do not smoke and drink alcohol for at least 24 hours before taking the test. Also, wear loose clothing and avoid large meals before the test, as these can help make it easier for you to take deep breaths.

Knowing the condition of the lungs with a spirometry test

A spirometry test is done to measure the total amount of air you can exhale, namely the forced vital capacity (FVC), as well as how much you exhale in the first second or what is known as 1 second forced expiration (FEV1).

Apart from the possible damage to your lungs, FEV1 is usually influenced by other factors, such as age, gender, height, or even race.

The comparison between FEV1 and FVC (FEV1 / FVC) will produce a percentage. That percentage will later be an indicator of whether you have lung problems or not.

That percentage also allows your doctor to know the extent of your lung disease.

FVC measurement

As previously explained, the FVC on the spirometry test shows the total amount of air that you can exhale by force.

The following is what the percentage of the FVC measurement results means:

• 80% or more: normal
• less than 80%: abnormal

An abnormal FVC result on a spirometric test can indicate a blockage in the airways, such as obstructive or restrictive lung disease.

FEV measurement 1

FEV1 in the spirometry test aims to measure the air you can forcefully exhale within 1 second. FEV1 can indicate the severity of your breathing problem.

According to the standards of the American Thoracic Society, the following is the meaning of the percentage of FEV1 measured by spirometry:

• 80% or more: normal
• 70% - 79%: abnormal, mild stage
• 60% - 69%: abnormal, moderate stage
• 50% - 59%: abnormal, moderate to severe stage
• 35% - 49%: abnormal, severe stage
• less than 35%: abnormal, very severe stage

FEV1 / FVC ratio measurement

The doctor will usually measure the FVC and FEV1 separately, then will calculate the FEV1 / FVC ratio. This ratio tells you how much your lungs are able to exhale in 1 second.

The higher the ratio, the healthier your lungs will be. In children aged 5-18 years, the ratio that indicates lung problems is less than 85%. Meanwhile, in adults it is less than 70%.

The role of spirometry in the treatment of respiratory diseases

The routine use of spirometry to see the progress of the disease is very important in the treatment of shortness of breath. Each disease with symptoms of shortness of breath has its own severity. Understanding the severity of your respiratory disease will help your doctor to recommend the best treatment according to the stage.

Your doctor will schedule regular check-ups and use the results of the spirometer to make adjustments to your medication. Not just drugs, in some cases treatment also includes surgery and lifestyle changes. A rehabilitation program is also sometimes needed to help improve your symptoms, slow disease progression, and improve quality of life.

The use of spirometry also allows the doctor to determine whether the treatment given is appropriate and effective and is effective according to your stage. The results of the examination will provide the doctor with information on whether your lung capacity is stable, increasing, or decreasing, so that treatment adjustments can be made.