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Flashcards in Ventilation Deck (28):
1

How are static lung volumes measured

spirometry

2

Tidal volume

Vol. entring/leaving the lung in single breath
includes gas exchange and dead space

3

Inspiratory reserve

Additional vol inspired over tidal vol (Exercise)

4

Expiratory reserve

Additional vol expired over tidal vol

5

Residual vol

Volume left in lungs after max forced expiration

6

Can residual vol be measured by spirometry

No, bse. you can't exhale it

7

Functional residual capacity

Vol. left in the lung after normal tidal vol/passive expiration

8

Vital capacity

Volume expired after maximal inspiration

9

Factors that affect vital capacity

Increase: sex (M>F) size, physical conditioning
decrease: age

10

Total lung capacity

Maximum vol. the lungs can hold

11

How can Functional residual capacity be measured

Helium dilution
Body plethysmograph

12

RV/TLC

less or equal to 25%

13

RV/TLC obstructive lung disease

Increases (Emphysema) - RV increases

14

Pt. appearance in increased RV (emphysema

Barrel chest

15

RV/TLC restrictive lung disease

Decreases (Fibrosis) - TLC decreases

16

Dead space

Volume of airways/lungs not involved in gas exchange

17

Anatomic dead space

Conducting zone (nose trachea, bronchi, bronchioles)
150ml (body wt in lbs)

18

Physiologic dead space

total volume of lungs not participating in gas exchange

19

When would we have functional dead space in alveoli

V/Q mismatch

20

What is physiologic dead space calculation based on

PP of CO2 in expired air

21

Assumptions for physiologic dead space calculation

-CO2 in expired air comes only from alveoli
-No CO2 in inspired air
-Physiologic dead sp`ace doesn't contribute CO2

22

Minute ventilation

Total rate of air in and out of the lungs

23

Alveolar ventilation

Volume which corrects for physiologic dead space

24

Rshp. btn. alveolar vent rate and Pa.CO2

Alveolar vent rate is inversely proportional to alveolar partial pressure of CO2

25

Forced vital capacity

total vol tht. can be forcibly expired after normal inspiration (time = 3sec total)

26

normal FEV1/FVC ratio

80%

27

Restrictive disease (fibrosis) FEV1/FVC ratio

Increased: both FEV1 and FVC decrease but FEV1

28

Obstructive disease (Asthma) FEV1/FVC ratio

Decreased: FEV1 and FCV decrease but FEV1>FCV so the ratio decreases