lung definitions Flashcards
Residual Volume
Air volume remaining in the lungs after maximal forced expiration.
FRC (Functional Residual Capacity)
Functional residual capacity is the volume of air remaining in the lungs after expiration of a normal breath. RV + ERV
IRV (Inspiratory Reserve Volume)
The extra volume of air that can be inspired with a maximal effort after a normal inspiration (psychological sigh)
Expiratory Reserve Volume (ERV)
Extra volume of air that can be forcefully expired after normal, quiet expiration
OPPOSITE OF PSYCHOLOGICAL SIGH
FVC (Forced Vital Capacity)
The volume of air maximally exhaled, after a maximum inspiration
Forced expiraoty volume 1
fraction of the vital capacity expired during the 1st second of forced expiration
FEV1 /FVC
ratio of the forced expiratory lung volume in the first second to the forced vital capacity of the lungs. indicates how much air you can forcefully exhale.
Closing capacity
closing volume + residual volume
what is V, Q,
what is a VQ mismatch
V = ventilation -> amount of air entering the alveoli
Q = perfusion -> blood flowing through capillaries surrounding the alveoli
V/Q mismatch occurs when this ratio is not properly matched (above or below 0.8)
There are 2 types of mismatch:
1.Dead space ventilation – an area that has adequate ventilation but inadequate perfusion (O2 can’t enter the blood stream)
2.Shunt – adequate blood flow (perfusion), but not enough ventilation