FEV1 values define the degree of obstruction:
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FEV1 is one of the most common indices used to assess airway obstruction, which helps in defining the severity of asthma, as well as evaluating how well treatment is working.
FEV1 is not the same as peak flow, which is determined with a device calledpeak flow meterthat measures the flow rate (speed) of the air blown out. When measured over time, changes in peak flow can be an indication of whether asthma is well controlled or not.
How FEV1 Is Used In Asthma Treatment
Your healthcare provider may order pulmonary function testing if you have certain respiratory symptoms, such as:
Although originally the only way to measure forced exhalation volume was in a healthcare provider’s office, it is now possible to do so using a home spirometer, allowing you and your healthcare provider to use FEV1 testing as part of your home monitoring for asthma.
Home Monitoring and Your Asthma Action Plan
Many asthma action plans use peak flows as one of the criteria for intervention on your part. You and your healthcare provider will determine what your personal best exhalation is and then base your action plan on a percentage of that number. So it is not really the actual number that is important in this case, but the relative changes that you see over time.
If you are going to use forced expiratory volume as part of your asthma action plan, you will need to talk with your healthcare provider about what sort of home spirometer might be best for you. There are a number of different models with different features and price points.
You will monitor and record your FEV1 over time, after which you and your healthcare provider will place specific FEV1 readings into your green, yellow, and red zones of the asthma action plan.
2 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Sharoon D, Edwards CW.Forced expiratory volume. In: StatPearls. Updated September 14, 2020.Globe G, Martin M, Schatz M, et al.Symptoms and markers of symptom severity in asthma–content validity of the asthma symptom diary.Health Qual Life Outcomes. 2015;13:21. doi:10.1186/s12955-015-0217-5Additional ReadingNational Heart, Lung, and Blood Institute.Expert panel report 3 (EPR3): Guidelines for the diagnosis and management of asthma. Published September 2012.
2 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Sharoon D, Edwards CW.Forced expiratory volume. In: StatPearls. Updated September 14, 2020.Globe G, Martin M, Schatz M, et al.Symptoms and markers of symptom severity in asthma–content validity of the asthma symptom diary.Health Qual Life Outcomes. 2015;13:21. doi:10.1186/s12955-015-0217-5Additional ReadingNational Heart, Lung, and Blood Institute.Expert panel report 3 (EPR3): Guidelines for the diagnosis and management of asthma. Published September 2012.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Sharoon D, Edwards CW.Forced expiratory volume. In: StatPearls. Updated September 14, 2020.Globe G, Martin M, Schatz M, et al.Symptoms and markers of symptom severity in asthma–content validity of the asthma symptom diary.Health Qual Life Outcomes. 2015;13:21. doi:10.1186/s12955-015-0217-5
Sharoon D, Edwards CW.Forced expiratory volume. In: StatPearls. Updated September 14, 2020.
Globe G, Martin M, Schatz M, et al.Symptoms and markers of symptom severity in asthma–content validity of the asthma symptom diary.Health Qual Life Outcomes. 2015;13:21. doi:10.1186/s12955-015-0217-5
National Heart, Lung, and Blood Institute.Expert panel report 3 (EPR3): Guidelines for the diagnosis and management of asthma. Published September 2012.
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