Lung volumes and Alveolar Ventilation Flashcards
What is Tidal Volume (VT)
Air inhaled and exhaled in normal respiration (~500ml)
What is the typical respiratory frequency?
~15 breaths/min
What is total ventilation (VE)?
Tidal volume x respiratory frequency
What does Tidal volume minus anatomic dead space equal to?
Amount of fresh air in alveoli
How do you calculate alveolar ventilation?
fresh air X respiratory frequency
What is spirometry?
Measurement of lung volumes and flow
What are the 3 different spirometers?
Volume displacement spirometers
Gas flow measurement devices
Peak Flow meters
What is the residual volume (RV)?
Volume of air that remains after forceful expiration
What is functional residual capacity (FRC)?
Amount of air remaining in the lungs after normal tidal expiration
What is total lung capacity (TLC)?
Maximum amount of air lungs can contain (RV X VC)
How are TLC, FRC and RV measured?
Gas dilution technique and body plethysmograph
What 5 things are pulmonary function tests used for?
Provide info on lung function
Assist with diagnosis of physiological abnormalities
Asses response to treatment
Determine fitness for surgical procedures
What is anatomical dead space (VD)?
Volume of air that does not take place in gas exchange
What is physiological dead space?
Sum of anatomical dead space plus alveolar dead space
What is alveolar dead space?
Areas of diseased tissue where gas exchange no longer occurs)
