Pulmonary Function Tests Flashcards
What is tidal volume?
Volume of air inspired and expired with each normal breath (~500mL)
What is forced vital capacity (FVC)?
Amount of air that can be forcefully expelled beginning with the lungs completely full and blowing maximally until the lungs are as empty as possible (~4600mL)
What is forced expiratory volume in first second (FEV1)?
Amount of air expelled during the first second of the FVC maneuver
What is residual volume (RV)?
Volume of air remaining in the lungs after the most forceful expiration (~1200mL)
What is total lung capacity (TLC)?
Max volume to which the lungs can be expanded with inspiration (~5800mL)
What are the indications for PFTs?
Dyspnea at rest or exertion, cough, asthma, COPD, suspected bronchiectasis or bronchiolitis, suspected ILD, suspected neuromuscular or chest wall disease
What is this graph?
Normal flow volume curve
What is this graph?
Normal flow volume loop
What does this graph show?
Moderate obstruction
What does this graph show?
Severe obstruction
What does this flow volume curve show?
Moderate restriction
What does this flow volume curve show?
Severe restriction
What does this flow volume loop show?
Variable extra thoracic obstruction (ex. vocal cord paralysis, airway burns, etc); flat inspiration and normal expiration
What does this flow volume loop show?
Variable intrathoracic obstruction (ex. airway trauma, airway inflammation, foreign body, etc); flat expiration, normal inspiration
What does this flow volume loop show?
Fixed obstruction (either intrathoracic or extra thoracic) include tracheal stenosis, bronchial stenosis, goiters, upper airway tumors
What does this flow volume loop show?
Obstructive lung pattern (lower airway)
