Forced vital capacity
Total volume of air in liters forcefully and rapidly exhaled in 1 breath
Forced expiratory volume 1 sec
Amount of air forcefully expired in 1 sec.
- Normal = >80% predicted value
- Determine severity of COPD
FEV1/FVC
Estimates presence and ant of obstruction in airways
- Obstruction = decreased ratio
- Restrictive = increased or normal ratio
Forced expiratory flow 25-75
Rate of air movement in medium and small airways (bronchioles & terminal bronchioles)
Peak expiratory flow rate
Measure of maximum airflow rate
- Large airway obstruction
- Severity of asthma exacerbation
- Used for home monitoring plans
Body plethysmography
Lung volume measures
- Pt sits in airtight bow and inhales/ exhales against shutter
- Measure pressure change within box during respiration
Functional residual capacity
volume of gas remaining at end of normal breath
Total lung capacity
- Total amount of gas continued in lungs at maximal inhalation
Inspiratory capacity
Difference between normal inhalation to maximal inhalation
Forced vital capacity
Amount of air that can be expired following maximal inspiration
Residual volume
Volume of air left in lungs at end of forced expiration to bottom of expiratory reserve volume
Pulse oximetry
Precautions blood oxygen level
Sodium chloride sweat test
Dx cystic fibrosis- pts have elevated NaCl levels in sweat
Toracentesis
Remove excess fluid from pleura and chest wall
- determine source of fluid & organisms
Polysomnography
Sleep study to eval sleep apnea
Bronchoscopy
Visualize airways and lungs
Diffusion capacity test
Assement of interstitial lung disease
- per minute transfer of gas using carbon monoxide, helium and air- measure concentration following exhalation
Airway reactivity test
Challenges to drop lung function
