Spirometry is a lung function test done in our office, often used to help diagnose or monitor asthma or "reactive airways". This may be used to evaluate a chronic cough as well. It measures lung volumes and air flow rates -- how quickly you can move air out of your lungs.
For this test, you will need to blow forcefully into a mouthpiece attached to a recording device (spirometer). The test determines how much air your lungs can hold and how quickly you can move air through your bronchial tubes. It will detect airway obstruction often associated with asthma, and can measure response to bronchodilator medications.
Some of the values that are measured with the spirometer are:
- Forced vital capacity (FVC). This measures the amount of air you can exhale after a deep inhalation, and reflects lung volume.
- Forced expiratory volume (FEV1). This measures the amount of air you can exhale with force within one second, and is reduced when there is obstruction such as in COPD or asthma.
- Forced expiratory flow 25% to 75%. This measures the air flow during the midportion of an exhalation, and detects more subtle airflow abnormalities deep in the smallest airways.
Results require interpretation by the physician to aid in diagnosis and management of your condition.