Pulmonary Physiology and Pulmonary Function Tests Flashcards
Four major factors that determine alveolar gas composition
- Inspired gas composition
- Mixed venous gas composition
- Alveolar ventilation
- Alveolar perfusion
Most frequently used objective tool to assess teh mechanical characteristics of the lung
FVC
Maximum volume expired after maximal inspiration
Vital capacity
Volume in lungs after maximal inspiration
Total Lung Capacity
Volume remaining in lungs after maximal exhalation
Residual volume
Volume in lungs at end of normal exhalation
Functional residual capacity (FRC)
Volume of spontaneous breath
Tidal volume (TV)
Maximum volume inspired from resting end expiratory position to total lung capacity
Inspiratory capacity
Volume expired from spontaneous end expiratory position
Expiratory reserve volume
Volume that can still be inspired from a spontaneous end inspiratory position
Inspiratory reserve volume
PFT technique most commonly used
Forced Expiratory Vital Capacity Maneuver
- Maximal inhalation followed by rapid and completed exhalation
FVC may be decreased due to what
- Intrinsic lung disease
- Pleural disease
- Chest wall restriction
- Respiratory muscle dysfunction
FEV1 decreased in what setting
Airway obstruction or restrictive disease
Normal range (FEV1/FVC ratio)
75-85%
- Decreased with age
- Increased in children (90%)
- Children have higher flow rates for their size
Low FEV1 with normal FEV1/FVC ratio
Restrictive lung disease process