Lung Volumes and Capacities

Question 1

Anatomic Dead Space Volume (VD)

Answer 1

The volume of air that occupies the non-respiratory conducting airways (~150 ml)

Question 2

Expiratory Reserve Volume (ERV)

Answer 2

The maximal volume of air that can be exhaled after a normal tidal exhalation (~1,200 ml)

Question 3

Forced Expiratory Volume (FEV)

Answer 3

The maximal volume of air exhaled in a specified period of time: usually the first, second, and third second of a FVC maneuver

Question 4

Forced Vital Capacity (FVC)

Answer 4

The volume of air expired during a forced maximal expiration after a forced maximal inspiration

Question 5

Functional Residual Capacity (FRC)

Answer 5

The volume of air in the lungs after normal exhalation (~2,400 ml)

FRC = ERV + RV

Question 6

Inspiratory Capacity (IC)

Answer 6

The maximal volume of air that can be inspired after a normal tidal expiration (~3,600 ml)

IC = TV + IRV

Question 7

Inspiratory Reserve Volume (IRV)

Answer 7

The maximal volume of air that can be inspired after a normal tidal volume inspiration (~3,100 ml)

Question 8

Minute Volume Ventilation (VE)

Answer 8

The volume of air expired in on minute

VE = TV x respiratory rate

Question 9

Peak Expiratory Flow (PEF)

Answer 9

The maximum flow of air during the beginning of a forced expiratory maneuver

Question 10

Residual Volume (RV)

Answer 10

The volume of gas remaining in the lungs at the end of a maximal expiration (~1,200 ml)

Question 11

Tidal Volume (TV)

Answer 11

Total volume inspired and expired with each breath during quiet breathing (~500 ml)

Question 12

Total Lung Capacity (TLC)

Answer 12

The volume of air in the lungs after a maximal inspiration; the sum of all lung volumes (~6,000 ml)

TLC = RV + VC or TLC = FRC +IC

Question 13

Vital Capacity (VC)

Answer 13

The volume change that occurs between maximal inspiration and maximal expiration (~4,800 ml)

VC = TV + ERV + IRV