Respiratory

Question 1

tidal volume (TV)

Answer 1

volume inspired or expired with each normal breath (or VT)

Question 2

inspiratory reserve volume (IRV)

Answer 2

1. volume that can be inspired over and above the tidal volume
2. used in exercise

Question 3

expiratory reserve volume (ERV)

Answer 3

the volume that can be expired after the expiration of the TV

Question 4

Residual volume (RV)

Answer 4

1. the volume that remains in the lungs after maximal expiration
2. cannot be measured by spiro

Question 5

Dead space is

Answer 5

anatomic plus physiologic

Question 6

anatomic dead space

Answer 6

1. volume in conducting airways

2. normally 150mL

Question 7

physiologic dead space

Answer 7

1. functional measurement

2. volume of lungs that does not participates in gas exchange

Question 8

minute ventilation is expressed as

Answer 8

VT x breaths/min

Question 9

alveolar ventilation

Answer 9

VA = (VT - VD) x Breaths/min

Question 10

inspiratory capacity

Answer 10

Inspiratory capacity = Tv + IRV

Question 11

Functional residual capacity (FRC)

Answer 11

1. FRC = ERV + RV
2. volume remaining in the lungs after a tidal volume is expired
3. includes RV, so it cannot be measured by spiro

Question 12

VC: vital capacity is

Answer 12

VC = TV + IRV + ERV

the volume of air that can be forcibly expired after maximal inspiration

Question 13

Total lung capacity (TLC)

Answer 13

1. sum of all 4 lung volumes
2. volume in the lungs after maximal inspiration
3. includes RV, so it cannot be measured by spirometry

Question 14

FEV1 is normally

Answer 14

80%

it is the volume of air that can be expired in the first second of a forced maximal inspiration

Question 15

FEV1/FVC in restrictive disease

Answer 15

increased

Question 16

FEV1/FVC in obstructive disease

Answer 16

ratio in decreased

Question 17

muscle of inspiration

Answer 17

1. diaphragm
2. external intercostals
3. accessory muscles

Question 18

muscles of expiration

Answer 18

expiration is normally passive

forced: abdominal muscles or internal intercostal muscles

Question 19

compliance is

Answer 19

1. the distensibility of lungs and chest wall
2. inversely proportional to elastace
3. is the slope of the pressure volume curve
4. is the change in volume for given change in pressure
5. C = V/P

Question 20

transmural pressure is

Answer 20

alveolar pressure minus intrapleural pressure

Question 21

when the pressure outside of the lungs is negative,

Answer 21

the lungs expand and LV increases

Question 22

when the pressure outside of the lungs is positive,

Answer 22

the lungs collapse and LV decreases

Question 23

hysteresis is

Answer 23

inflation of the lungs follows a different curve than deflation

this is due to the need to overcome surface tension forces when inflating the lungs

Question 24

when is compliance the lowest and highest?

Answer 24

the lowest at high expanding pressures.,

the highest at mid ranges of pressure

Question 25

emphysema effect on compliance

Answer 25

increased lung compliance and the tendency of the lung to collapse is decreases

tendency of lungs to expand and not collapse results in barrel chested appearance

higher FRC

Question 26

fibrosis and lung compliance

Answer 26

lung compliance is decreased and the tendency of the lung to collapse is increased

lower FRC