Spirometry is a standard test doctors use to determine how well your lungs function. A score that measures airflow into and out of your lungs can help diagnose COPD and determine the best treatments.
Spirometry is an important tool for diagnosing and determining treatment for chronic obstructive pulmonary disease (COPD).
This breathing test can detect COPD in its earliest stage, even before any obvious symptoms are noticeable.
Healthcare professionals can use these types of tests to help track COPD’s development, how it progresses, and what treatments people may need to live with this condition.
Spirometry testing is done in a doctor’s office using a spirometer. This device measures lung function and records the results, which are also displayed on a graph.
Your doctor will ask you to take a deep breath and then blow out into the mouthpiece on the spirometer as hard and fast as possible.
It measures the total amount you were able to exhale, called the forced vital capacity (FVC). The test also measures how much you exhaled in the first second, known as FEV1. Other factors also influence your FEV1, including your:
- age
- sex
- height
- weight
The FEV1 is calculated as a percentage of the FVC (FEV1/FVC).
A low percentage confirms airflow obstruction, which can then be used to help determine what might cause that airflow obstruction: COPD, asthma, cystic fibrosis, or another condition.
Your doctor will use a spirometer to regularly monitor your lung function and help track the progression of your COPD.
The test can help determine COPD staging. Depending on your FEV1 and FVC readings, your doctor will stage your COPD based on the following:
COPD stage 1
The first stage is considered mild.Your FEV1 is equal to or greater than the predicted normal values with an FEV1/FVC of 70% or less.
In this stage, your symptoms are most likely to be very mild.
COPD stage 2
Your FEV1 falls between 50% and 79% of the predicted normal values with an FEV1/FVC of less than 70%.
Symptoms, like shortness of breath after activity, cough, and sputum production, are more noticeable. Your COPD is considered to be moderate.
COPD stage 3
Your FEV1 is between 30% and 49% of the normal predicted values, and your FEV1/FVC is less than 70%.
In this stage, you may experience shortness of breath, fatigue, and a lower tolerance to physical activity. Episodes of COPD exacerbation are also common in severe COPD.
COPD stage 4
This is the most severe stage of COPD. Your FEV1 is less than 30% of normal predicted values or less than 50% with chronic respiratory failure.
At this stage, your quality of life is greatly impaired. COPD exacerbations can be life threatening.
Learn more about COPD and its different stages.
Regular use of spirometry for COPD progression tracking is important for COPD treatment.
Each stage comes with its own unique issues. Understanding your disease’s stage allows your doctor to recommend and prescribe the best possible treatment.
While staging helps create standard treatments, your doctor will consider your spirometer results and other factors to create a personalized treatment for you.
When it comes to rehabilitation therapy, such as exercise, they’ll consider factors like other health conditions you may have and your current physical condition.
Your doctor will schedule regular tests and use the spirometer results to adjust your treatment as needed. These can include recommendations for medical treatments, lifestyle changes, and rehabilitation programs.
Spirometry assists in staging and treatment recommendations. It also allows your doctor to check whether your treatment is working.
The results of your tests can tell your doctor whether your lung capacity is stable, improving, or decreasing so that adjustments to treatment can be made.
COPD is a chronic (long-term) condition that doesn’t have a cure. But treatments and lifestyle changes can help reduce your symptoms, slow disease progression, and improve your quality of life.
A spirometry test is a tool you and your doctor can use to determine which COPD treatments are right for you at each stage of the disease.