Lung Volumes and Capacities

Question 1

Vital Capacity (VC)

Answer 1

the volume change that occurs between max inhale and max exhale

VC= TV + IRV + ERV

VC is roughly 75% of total lung volume

Question 2

Residual Volume (RV)

Answer 2

volume of gas remaining in the lungs at the end of a max exhale

Approximately 25% of total lung volume

Question 3

Tidal Volume (TV)

Answer 3

total volume inspired and expired with each breathing during quiet breathing

approximately 10% of total lung volume

Question 4

Total Lung Capacity (TLC)

Answer 4

volume of air in the lungs after a maximal inhale; the sum of all lung volumes (RV + VC or FRC + IC)

Question 5

Functional Residual Capacity (FRC)

Answer 5

volume of air in the lungs after normal exhalation (ERV + RV)

approx. 40% of total lung volume

Question 6

Inspiratory Capacity (IC)

Answer 6

maximal volume of air than can be inhaled after a normal tidal exhale (TV +IRV)

approx. 60% of total lung volume

Question 7

Inspiratory Reserve Volume (IRV)

Answer 7

maximal volume of air than can be inspired after normal tidal volume inspiration

approx. 50% of total lung volume

Question 8

Peak Expiratory Flow (PEF)

Answer 8

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

Question 9

Minute Volume Ventilation (VE)

Answer 9

volume of air expired in one minute (TV x respiratory rate)

Question 10

Forced Vital Capacity (FVC)

Answer 10

volume of air expired during the forced maximal expiration after a forced max inspiration

Question 11

Forced Expiratory Volume (FEV)

Answer 11

maximal volume of air exhaled in a specified period of time which is usually the 1st, 2nd, and 3rd second of a forced vital capacity manuever

Question 12

Expiratory Reserve Volume (ERV)

Answer 12

maximal volume of air than can be exhaled after a normal tidal exhalation

Approx. 15% of total lung volume

Question 13

Anatomic Dead Space Volume (VD)

Answer 13

volume of air than occupies the non-respiratory conducting airways