Waters I

Question 1

What is ventilation?

Answer 1

the volume of air moving into or out of the lungs per unit time

Question 2

What is a normal tidal volume?

Answer 2

500mL

Question 3

What is functional residual capacity?

Answer 3

the volume of air in the lungs after tidal expiration

Question 4

What is residual volume?

Answer 4

the amount of air remaining after maximal expiration

Question 5

What is forced vital capacity (FVC)?

Answer 5

aka vital capacity. equals the tidal volume + max inspiration and expiratory reserves

Question 6

Forced expiratory volume (FEV1)

Answer 6

the forced expiratory volume in 1 sec after maximal inspiration

Question 7

What is a normal FEV1/FVC ratio?

Answer 7

80%

Question 8

Patients with ____ typical have FEV1:FVC ratios less than 70%

Answer 8

obstructive lung disease

Question 9

Why would patients with obstructive lung disease have FEV1:FVC ratios less than 70%?

Answer 9

it is difficult to expire rapidly through narrowed airways

Question 10

What are some common examples of obstructive lung disease?

Answer 10

• asthma
• COPD
• emphysema
• chronic bronchitis
• bronchiectasis

Question 11

How does the FEV1:FVC change in restrictive lung disease?

Answer 11

It doesn’t! In these disease, FVC is reduced and the FEV1:FVC ratio may be normal or even increased

Question 12

What are some common examples of restrictive lung disease?

Answer 12

• obesity inhibiting normal breathing mechanics
• weakness of breathing muscles
• neuromuscular disorder
• pulmonary fibrosis
• sarcoidosis
• hypersensitivity pneumonitis

Question 13

What is anatomic dead space?

Answer 13

the volume of conducting airways not involved in gas exchange

Question 14

What is functional/alveolar dead space?

Answer 14

the volume of respiratory airways/alveoli not able to participate in gas exchange (usually due to pathology)

Question 15

What is the eqn. for minute ventilation?

Answer 15

tidal volume*respiratory rate

Question 16

What is alveolar ventilation?

Answer 16

the total volume of fresh air entering the alveoli per minute (aka the true portion available for gas exchange)

Question 17

What is the eqn for alveolar ventilation?

Answer 17

(TV-dead space)*respiratory rate

Question 18

Note: Dead space ventilation decreases as a % of minute volume. So alveolar ventilation increases with exercise

Answer 18

Similarly, the ratio of minute:alveolar ventilation also increases with exercise

Question 19

For a healthy individual, the dead space ventilation is roughly ___% minute ventilation

Answer 19

25-30%

Question 20

T or F. Slow, deep breaths increase the amount of alveolar ventilation

Answer 20

T. While rapid, shallow breathing decreases it

Thus, increasing the depth of breathing is more effective than increasing the breathing rate for increased oxygen perfusion