Pulmonary function testing, or spirometry, measures the mechanical function of the lung, chest wall, and respiratory muscles by assessing the total volume of air inhaled and exhaled from the lungs as well as air flow rates.
What to Expect:
You’ll be asked to inhale as much as possible and then exhale rapidly and forcefully for as long as air flow can be maintained.
Why It Is Done:
A reduction in the amount of air exhaled may indicate a variety of conditions, including:
- reduction in the maximum inflation of the lungs (TLC),
- obstruction of the airways
- loss of lung elastic recoil
- respiratory muscle weakness.
- ability of oxygen diffusing from the lungs into the blood.
Airway obstruction is the most common cause of reduction lung capacity. This test is used to assess the reversibility of airway obstruction.
What the Test Shows:
Spirometry is used to:
- establish baseline lung function
- detect pulmonary disease
- monitor the effects of therapies used to treat respiratory disease
- evaluate respiratory impairment
- Estimate risk for surgery
- evaluate potential occupational-related lung disease
- demonstrate various abnormalities of the larger central airways