The role of spirometry in the diagnosis and management of asthma

Spirometry is a common and easy-to-perform lung function test that can be used in the diagnosis of asthma and subsequent management of the condition.

1. What is asthma

Asthma is a long-term inflammatory disease that causes swelling and production of extra mucus inside the airways of the lungs. It can make breathing quite difficult, as the swelling narrows the airways, leading to cough, shortness of breath and other respiratory symptoms.

The condition is thought to be caused by genetic factors as well as environmental factors, such as exposure to pet dander, pollen, dust mites or mold, cleaning chemicals or smoke. Although there is currently no cure, asthma can be treated to make the symptoms more manageable.

1. Symptoms to watch out for

You may want to see your physician if you experience the following:

• Coughing and shortness of breath
• Chest tightness or pain
• Trouble sleeping or waking up at night because of the cough or breathing difficulties
• Wheezing, i.e. a characteristic whistling sound made by patients when they breathe out (this is a common sign of asthma in children)

It is also common for the aforementioned symptoms to worsen when you are suffering from a respiratory infection, such as cold or flu, or after intense physical activity.

1. Diagnosis of asthma

In order to correctly diagnose asthma, your physician will start by discussing your personal and medical history. You will be asked about allergies, family members with a history of asthma and allergies, and environmental factors that may have contributed to trigger your symptoms (e.g. exposure to chemicals or smoke in the workplace).

Your doctor will also keep an eye on other factors that may have an impact on your overall health status, such as age, height and body weight, and ask for a blood test.

At this point, the doctor will probably ask you to run a lung function test, and that is where spirometry comes in.

1. The role of spirometry in the diagnosis of asthma

Spirometry is a lung function test, also known as pulmonary function test, that can help your physician in the diagnosis of asthma by measuring the air flow you are able to breathe in and out, as well as how fast you can exhale. Common measures include the volume of air you can exhale in one second (FEV1), the total amount of air you can exhale (FVC), and FEV1/FVC ratio.

The test is non-invasive and can be easily run in the doctor’s office. You will need to breathe in deeply and then exhale forcefully into a mouthpiece connected to a device called spirometer. The spirometer will measure and keep track of the airflow in order to detect obstructive patterns.

If the objective of your spirometry test is to detect asthma, you may be asked to run the test before and after taking a bronchodilator, a specific medication that can help open your airways.

1. Managing asthma with spirometry

If a diagnosis of asthma is confirmed, your doctor will create a treatment plan according to your personal needs.

Although the best way to keep the disease under control is to recognize and avoid triggers, this is not always possible, which is why a treatment plan will likely include medicines to manage the symptoms and prevent them from worsening.

Spirometry can also be a useful way to keep track of your progression: when run periodically, it helps monitoring your lung condition over time, and is also a tool to evaluate the effectiveness of medication and treatments.

1. Choosing the best spirometer for accurate results from your tests

With over 30 years of experience, MIR is a world-renowned company in the field of oxymetry and respiratory care. With several different solutions for the diagnosis of respiratory diseases in professional diagnostic, primary care, personal care and clinical trials, MIR products are available in more than 100 countries.