resp physio 2

Question 1

define tidal volume

Answer 1

Amount of air you move into & out of your lungs during rest
not forced

Question 2

define forced vital capacity

Answer 2

Maximum volume of air into & out of your lungs in a single respiratory cycle

Question 3

define inspiratory reserve volume

Answer 3

the air that can be forcibly inhaled after inspiration of normal tidal volume

Question 4

define expiratory reserve volume

Answer 4

Additional air that can be forcible exhaled after expiration of a tidal volume

Question 5

how do you calculate forced vital capacity?

Answer 5

Inspiratory reserve capacity + tidal volume + expiratory reserve volume

Question 6

define residual volume

Answer 6

Volume of air that remains in the lungs even after maximal exhalation

Question 7

what is FEV1/FVC?

Answer 7

a ratio of Forced Expiratory Volume in 1 sec & Forced Vital Capacity

Question 8

what values are normal for FEV1/FVC?

Answer 8

70-80%

Question 9

what effect does asthma have on FEV1/FVC?

Answer 9

decreases it

Question 10

what generates the pressure differences for breathing?

Answer 10

respiratory muscles

Question 11

how does FEV1/FVC change in restrictive lung disorders?

Answer 11

FEV1 is reduced in proportion to loss of lung volume (FVC) so no change in ratio.
These two values are reduced by about 20- 30% the normal value.

Question 12

how does FEV1/FVC change in obstructive lung disorders?

Answer 12

o FEV1 is lowered due to obstruction while FVC does not decrease much. So, the ratio is decreased

Question 13

what occurs in restrictive lung disease?

Answer 13

harder to fully expand airways due to damage to lung tissue

Question 14

what occurs in obstructive lung disease?

Answer 14

narrowing of airways

Question 15

what are the two main muscles involved in quiet respiration?

Answer 15

diaphragm

external intercostals

Question 16

what movements do the external intercostals carry out?

Answer 16

o Pump-handle movements: anterior end of each rib elevated

o Bucket handle: diameter of chest increases by rib on either side

Question 17

why is expiration in quiet breathing passive?

Answer 17

elastic recoil of the lungs

Question 18

what muscles are involved in forced inspiration?

Answer 18

Diaphragm, external intercostal muscles; accessory muscles (E.g. Pectoralis major; minor, Serratus anterior)

Question 19

what muscles are involved in forced expiration?

Answer 19

Involves accessory respiratory muscles (E.g. Anterior abdominal muscles; quadratus lumborum).

Question 20

what is alveolar ventilation?

Answer 20

portion of total ventilation that reaches alveoli

Question 21

what is the anatomical dead space?

Answer 21

air that is inhaled but isn’t used in gas exchange

found in the mouth, pharynx, trachea and bronchi up the terminal bronchioles

Question 22

how much is anatomical dead space?

Answer 22

150ml

Question 23

what is alveolar dead space and what causes it?

Answer 23

dead space due to age/disease (e.g. in alveoli with insufficient blood supply)

Question 24

in healthy individuals, how much is the alveolar dead space?

Answer 24

5ml

Question 25

what is physiological dead space?

Answer 25

anatomic dead space + alveolar dead space

Question 26

what does a vitalograph measure?

Answer 26

the air flow rather than the air volume

Question 27

what is peak expiratory?

Answer 27

maximum rate at which air is expelled from the lungs

Question 28

what is forced expiratory volume?

Answer 28

how much air a person can exhale in one second