A Spirometer is a device that measures lung volumes, through the forced expiration of air in our lungs.
The standard indices are:
Forced Expired Volume in one second (FEV1)
- how much air can be exhaled in the first second of exhalation.
Forced Vital Capacity (FVC)
- the maximum volume of air that can be forcibly expired.
Ratio of FEV1/FVC as %
- the proportion of total volume that can be expired in the first second of expiration.
Readings are both reproducible and objective and there are well-defined normal ranges that allow for the effects of age, race, sex and height.
Spirometry is a quick and relatively simple means of distinguishing between obstructive disorders (COPD, Asthma) and restrictive disorders. It is also the measurement of choice for diagnosing and evaluating severity of COPD.