The FEV1/FVC ratio can help determine whether your condition isrestrictive or obstructiveand how severe the restriction or obstruction is.
This test can also monitor lung disease.
The test can be performed in a healthcare provider’s office and takes about 45 minutes to complete.
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A Word From Verywell
Heart and lung health are important predictors of longevity.
Therefore, it’s important to understand how well your lungs are doing.
Examples include:
Risks and Contraindications
Spirometry is a safe, non-invasive test.
It involves breathing into a tube attached to a meter that measures the volume and/or force of airflow.
There are few side effects associated with spirometry.
Some people may feel lightheaded, have shortness of breath, or cough when blowing into the spirometer.
If you have asthma, there is a small risk of anasthma attack.
Percentages below the predictive value are considered abnormal.
The lower the percentage, the more severe the lung condition generally is.
In most cases, this would be correct.
However, once-off spirometry doesn’t always expose conditions like mild to moderate COPD.
Because of this, repeated spirometry may be needed to return an accurate result.
Restrictive problems occur when a person can’t inhale deeply due to the loss of lung capacity.
Overlapping restrictive and obstructive lung diseases can do the same.
If the ratio improves with a bronchodilator, that means that the obstruction is at least partially reversible.
This is usually seen with conditions such as asthma.
For obstructive lung conditions, your healthcare provider may retest your FEV1/FVC ratio.
With some conditions, like asthma, your ratio may improve after using a bronchodilator.
Summary
The FEV1/FVC ratio indicates how much air it’s possible for you to forcefully exhale.
It’s measured by spirometry, a test used to diagnose or monitor lung conditions.
If you have a restrictive condition, you may need more pulmonary function tests to help diagnose your condition.
If your lung condition is obstructive, your healthcare provider may recommend using a bronchodilator.
It is also possible to have a mixed defect in which there is both restriction and obstruction.
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