Lung Volumes & Capacities

Question 1

What does FEV1 mean?

Answer 1

Forced expiratory volume in 1 sec

Usually ~0.75FVC (FEF75)

Question 2

What is the procedure for forming a flow/volume curve and finding FVC?

Answer 2

1. Breathe in to total lung capacity
2. Exhale as fast as possible in one second
3. Volume produced is the forced vital capacity (FVC) in 1 sec

Question 3

What is FVC?

Answer 3

Forced vital capacity, the total amount of air forcibly expired

Question 4

FEV, what us normal and low level?

Answer 4

FEV1 , 80% or greater than predicted value - normal

Less than 80% - low

Question 5

What is airway obstruction?

Answer 5

FEV1/FVC less than 0.7
COPD, asthma
Blocked

Question 6

What is airway restriction?

Answer 6

FVC<0.8
Pulmonary fibrosis
Decreased expansion ability

Question 7

What is the tidal volume?

Answer 7

Amount of air inhaled or exhaled in one breath - 500ml a breath

Question 8

What is Inspiratory Reserve Volume?

Answer 8

Amount of air in excess of tidal inspiration that can be inhaled with max effort

Question 9

What is expiratory reserve volume?

Answer 9

Max exhalation excess of normal exhalation

Question 10

What is residual volume?

Answer 10

Air in lungs after max expiration

Question 11

What is total lung capacity?

Answer 11

TLC = IRV + TV + ERV + RV

Question 12

What is inspiratory capacity?

Answer 12

IC = TV + IRV

Max amount of air that can be inhaled after TV

Question 13

What is vital capacity?

Answer 13

VC = ERV + TV + IRV

Question 14

What is functional residual volume?

Answer 14

FRC = RV + ERV