Respiratory Lung Volumes Flashcards
“In and out like the tide”
Volume inspired and expired with each breath at rest
- 500ml in males
- 350ml in females
Tidal Volume (TV)
“Maximum, inspired, normal”
Maximum volume of air that can be inspired at the end of a normal tidal inspiration
Inspiratory Reserve Vol (IRV)
TV + IVR
Inspiratory Capacity (IC)
“Maximum, expired, normal”
Maximum volume of air that can be expired at the end of a normal tidal inspiration
Expiratory Reserve Volume (ERV)
“It resides so it remains” - it gets minimal EXposure
Volume of air remaining after minimal expiration
Increases with age
Residual volume (RV)
= ERV + RV
= 2.2L in a young man
Functional Residual Capacity
“Maximum, expired, maximum” 2 maximums, so its vital
Maximum volume of air that can be expired after maximum inspiration
= IC + ERV
Decreases with age
- 4500ml in males
- 3500ml in females
Vital Capacity (VC)
= TV x ((PaCO2 - PeCO2) / PaCO2)
Physiological Dead Space
= VC + RV
Total Lung Capacity
