lecture 3 & 4

Question 1

define residual volume

Answer 1

the volume of gas in the lungs at the end of maximal expiration

Question 2

define tidal volume

Answer 2

the volume of air breathed in or out of the lungs at each breathe

Question 3

define expiratory reserve volume

Answer 3

the maximum volume of air that expelled from the lungs at the end of normal expiration

Question 4

define inspiratory reserve volume

Answer 4

the maximum volume of air that can be drawn into the at the end of a normal inspiration

Question 5

define vital capacity

Answer 5

tidal volume + inspiratory reserve volume +expiratory reserve volume

Question 6

define total capacity

Answer 6

vital capacity plus the residual volume

Question 7

define ispiratory capacity

Answer 7

tidal volume + inspiratory reserve volume

Question 8

define functional residual capacity

Answer 8

expiratory reserve volume + residual volume

Question 9

what is FEV1

Answer 9

forced expired volume in 1 second

Question 10

what is FEV1:FVC

Answer 10

fraction of forced vital capacity expired in 1 second

Question 11

what does ventilation mean

Answer 11

broadly and simply ventilation refers to movement of air into and out of the lungs

Question 12

What are the 2 types of ventilation

Answer 12

pulmonary ventilation and alveolar ventilation

Question 13

describe what pulmonary ventilation is

Answer 13

total air movement into/out of lungs

Question 14

describe what alveolar ventilation is

Answer 14

FRESH air getting to the alveoli and therefore available

Question 15

what is atmospheric pressure (value)

Answer 15

760mmHg

Question 16

what is the partial pressure of oxygen (value)

Answer 16

160mmHg

Question 17

during hyperventilation will alveoli ventilation increase or decrease

Answer 17

increased alveolar ventilation as Po2 rises to 120 and Pco2 falls to 20

Question 18

during hypo ventilation will alveolar ventilation increase or decrease

Answer 18

decrease as Po2 falls to 30 and Pco2 rises to 100

Question 19

surfactant is produced by alveolar cells why is it useful to alveoli

Answer 19

surfactant reduces tension on alveolar surface membrane thus reducing tendency for alveoli to collapse

Question 20

when does sufactant production start during pregnancy

Answer 20

25 weeks gestation

Question 21

when is surfactant production complete

Answer 21

by 36 weeks

Question 22

what stimulates surfactant production

Answer 22

thyroid hormones and cortisol (which increase towards the end of pregnancy

Question 23

what does compliance mean/represent

Answer 23

it represents stretchability of the lungs

Question 24

define high compliance

Answer 24

large increase in lung volume for small decrease in ip pressure

Question 25

define low compliance

Answer 25

small increase in lung volume for large decrease in ip pressure

Question 26

what is emphysema

Answer 26

loss of elastic tissue - means expiration requires effort

Question 27

alveolar ventilation declines in what direction in the lungs

Answer 27

declines with height from the base to the apex

Question 28

compliance also declines in the lungs, what pattern does this follow

Answer 28

compliance declines with height from the base to the apex due to alveoli at the apex being more inflated at FRC. At the base alveoli are more compressed

Question 29

a small change in pressure will bring about a larger change in volume where, the base or the apex

Answer 29

the base

Question 30

define anatomical dead space

Answer 30

the volume of air taken in during each breathe the does not mix with the air in the alveoli

Question 31

physiological dead space includes alveoli that are ventilated but not perfused with blood. True or false?

Answer 31

True