Physiology and function in restrictive lung diseases (pre rec)

Question 1

what is an obstructive disorder

Answer 1

a disorder in which the radius of an airway is narrowed, thus reducing airflow in and out of the lungs

Question 2

what is a restrictive disorder

Answer 2

a disorder in which prevents normal expansion of the lungs

Question 3

what can lung restriction be due to

Answer 3

extra-pulmonary or intra-pulmonary disease

Question 4

extra-pulmonary disease affects which structures

Answer 4

visceral pleura, pleural space, chest wall including parietal pleura, bones, muscles, nerves

Question 5

intra-pulmonary disease affects which structures

Answer 5

alveoli and surrounding lung tissue

Question 6

conditions causing extrapulmonary restriction examples

Answer 6

myasthenia gravis, muscular dystrophy, asbestos exposure, scoliosis

Question 7

affect of asbestos exposure

Answer 7

pleural thickening

Question 8

conditions that might cause intra-pulmonary restriction?

Answer 8

silicosis, asbestosis, drug induced lung fibrosis, pneumoconiosis, rheumatoid-lung, bird-fanciers lung

Question 9

name for difference between lung elastic recoil pressure and chest wall elastic recoil pressure

Answer 9

transpulmonary pressure

Question 10

what pressure do we need to overcome in order to inflate the lungs

Answer 10

transpulmonary pressure

Question 11

what is the measure of distensibility (stretch-ability) of a tissue

Answer 11

compliance

Question 12

lung with low compliance feature?

Answer 12

greater inflation pressure required to inflate lung
generates more elastic recoil - deflation is easy

Question 13

lung with high compliance features?

Answer 13

smaller inflation pressure required to inflate lung
less elastic recoil - deflation is hard

Question 14

result of increased fibrous tissue?

Answer 14

more ridged, decreased compliance

Question 15

result of decreased elastic tissue

Answer 15

more floppy, increased compliance

Question 16

example of increased compliance condition

Answer 16

emphysema

Question 17

example of decreased compliance

Answer 17

lung fibrosis

Question 18

what lines the alveoli

Answer 18

alveolar epithelial lining fluid

Question 19

effect of alveolar epithelial lining fluid

Answer 19

increases alveolar pressure due to surface tension of fluid

Question 20

size of spheres effect on contribution of surface tension?

Answer 20

in larger spheres surface tension contributes less

Question 21

what prevents the alveoli from collapsing and being unstable

Answer 21

surfactant

Question 22

what is surfactant produced by

Answer 22

type 2 alveolar epithelial cells

Question 23

difference in shape between 2 alveolar cells

Answer 23

type 1 - flat
type 2 - cuboidal

Question 24

what is surfactant composed of

Answer 24

lipids (90%) and proteins (10%)

Question 25

function of surfactant

Answer 25

reduce surface tension

Question 26

surfactant molecule structure

Answer 26

hydrophobic end composed of fatty acids (gas)
hydrophilic end composed of glycerol, phosphate, choline (liquid)

Question 27

difference in distribution of surfactant molecules in large/expanded and small/deflated alveoli?

Answer 27

large - spread out with water molecules
small - closer together

Question 28

what do surfactant molecules in smaller/deflated alveoli do? how?

Answer 28

reduce surface tension because they are closer together

Question 29

how does surfactant stop one smaller alveoli emptying into a nearby larger one

Answer 29

maintains equal pressure between alveoli

Question 30

what disease is caused by lack of surfactant in neonates

Answer 30

respiratory distress syndrome of the newborn

Question 31

what does surfactant deficiency contribute to in adults

Answer 31

adult respiratory distress syndrome
pneumonia
idiopathic pulmonary fibrosis
lung transplant

Question 32

obstructive lung disease difference in measurements

Answer 32

FEV1 reduced
FVC normal
FEV1/FVC ratio reduced
TLC increased (lung hyperinflation)
VC reduced
RV increased

Question 33

restrictive lung disease difference in measurements

Answer 33

FEV1 reduced
FVC reduced
FEV1/FVC ratio normal or increased
TLC reduced
VC reduced
RV normal or reduced

Question 34

how to distinguish extra from intra pulmonary restriction with physiological measurements

Answer 34

measure gas transfer

Question 35

what does gas transfer measure

Answer 35

gas exchange and alveolar volume

Question 36

what gas is used to measure gas exchange and why

Answer 36

carbon monoxide - rapidly taken up by haemoglobin with high affinity, not produced by body, non-toxic and easy to measure

Question 37

what gas is used to measure alveolar volume and why

Answer 37

helium - not taken up by haemoglobin, not produced by body, non toxic, easy to measure

Question 38

carbon monoxide gas transfer measurement

Answer 38

??????? - on slides week 5 pre rec

Question 39

difference in TLCO and KCO between extra and intra

Answer 39

extra - TLCO low, KCO normal
intra - TLCO low, KCO low