Respiratory volumes and capacities

expiratory reserve volume

amount that can be forcefully expired after expiration of the tidal volume (100 mL at rest)

inspiratory reserve volume

amount that can be inspired forcefully after inspiration of the tidal volume (3000 mL at rest)

alveolar ventilation rate (AVR)

The volume of air available for gas exchange per minute is called ______, and it is calculated as follows: Va = f(VT - VD) Va = alveolar ventilation (milliliters per minute) f = respiratory rate (frequency; breaths per minute) VT = tidal volume (milliliters per respiration) VD = dead space (milliliters per respiration)

tidal volume

amount of air inspired or expired with each breath; at rest: 500 mL

functional residual capacity

expiratory reserve volume + residual volume

total lung capacity

inspiratory reserve volume + expiratory reserve volume + tidal volume + residual volume

vital capacity

inspiratory reserve volume + tidal volume + expiratory reserve volume

spirometer

measures volumes of air that move into and out of respiration an instrument consisting of a hollow bell inverted over water; used to evaluate respiratory function

forced expiratory volume (FEV)

the amount of gas expelled during specific time intervals of the FVC (forced vital capacity) forced vital capacity - gas forcibly expelled after taking a deep breath

inspiratory capacity

tidal volume + inspiratory reserve volume

minute ventilation (a.k.a. minute respiratory volume (MRV))

total air moved into and out of respiratory system each minute; tidal volume x respiratory rate respiratory rate = # of breaths taken per minute

residual volume

volume still remaining in respiratory passages and lungs after most forceful expiration (1200 mL)