Breathing Circuits Flashcards
2 types of Dead space
Anatomic
Physiological
Tidal volume (Vt) - in the adult male.
volume of air inspired or expired with each normal breath -
Normal TV in adult male
about 500 cc
Inspiratory Reserve Volume–>
volume of air that can be inspired over and above the normal VT when the person inspires with full force
Normal IRV
about 3000 cc.
Expiratory reserve volume (ERV) -
maximum extra volume of air that can be expired by forceful expiration after the end of a normal tidal expiration
Normal ERV
about 1100 cc.
Residual Volume (RV) -
volume of air remaining in the lungs after the most forceful expiration
Normal RV is
about 1200 cc.
What is a capacity?
It is a combination of 2 or more volumes
Inspiratory capacity =
VT + IRV = amount of air a person can breathe in. beginning at the normal expiratory level and distending the lungs to the maximum amount.
Normal Inspiratory Capacity
about 3500 mL
FRC (functional residual capacity) =
ERV + RV. The amount of air that remains in the lungs at the end of normal expiration
Normal FRC
About 2300 mL
VC vital capacity equals the ______
inspiratory reserve volume plus the tidal volume plus the expiratory reserve volume.
Vital Capacity is the
maximum amount of air a person can expel from the lungs after first filling the lungs to their maximum extent and then expiring to the maximum extent
What is a normal capacity ?
about 4600 mL
TLC total lung capacity =
VC + RV
TLC definition
The maximum volume to which the lungs can be expanded with the greatest possible effort (about 5800 cc); it is equal
Normal TLC
5800 ml
Formula for VE (minute ventilation)
TV x RR
IRV + VT + ERV =
VC
VC + RV =
TLC
ERV + RV =
FRC
