Respiratory physiology

Question 1

what is in-between the 2 layers of pleura

Answer 1

few mls of fluid

Question 2

is inspiration or expiration passive?

Answer 2

expiration is passive

Question 3

What do sensory receptors assess

Answer 3

flow, stretch

Question 4

where is airway resistance highest

Answer 4

main airways

Question 5

what is dead space?

Answer 5

air is supplied but no gas exchange takes place

Question 6

where is the respiratory bronchiole located

Answer 6

centre of acinus

Question 7

what happens when an area of the lung becomes hypoxic

Answer 7

pulmonary constriction to that area

to maximise ventilation- perfusion for optimal gas exchange

Question 8

how does CO influence oxygenation curve

Answer 8

CO has a greater infinity for Hb than O2 does

so presence of CO shifts curve to the left (higher affinity)

Question 9

what causes hypoxaemia (low O2 concentration in blood)

Answer 9

Alveolar hypoventilation (low ventilation)
reduced PiO2
ventilation/ perfusion mismatch
diffusion abnormality

Question 10

how is CO2 carried

Answer 10

Bound to Hb
dissolved in plasma
as HCO3-

Question 11

what causes high CO2

Answer 11

reduced minute ventilation
inc in dead space ventilation by rapid, shallow breathing and perfusion/ ventilation mismatch
inc CO2 production

Question 12

weak Base or weak acid?
HCO3-
H2CO3

Answer 12

HCO3- = weak base 
H2CO3= weak acid

Question 13

Can volatile acids be removed by the lungs?

Answer 13

yes

Question 14

how is carbonic acid removed

Answer 14

volatile acid

in equilibrium with volatile CO2

Question 15

how is non-volatile acid removed

Answer 15

buffered by body proteins or extracellular buffers

renal excretion

Question 16

what is the henderson- hasselbalch equation used for

Answer 16

calculate pH

Question 17

respiratory acidosis

Answer 17

increased PaCO2
decreased pH
mild increase HCO3-

Question 18

resp alakalosis

Answer 18

Decreased PaCO2
increase pH
mild decrease HCO3-

Question 19

metabolic acidosis

Answer 19

reduced bicarbonate and decreased pH

Question 20

metabolic alkalosis

Answer 20

increased bicarbonate and increased pH

Question 21

equation for lung pressure

Answer 21

flow x resistance

Question 22

difference between type 1 and type 2 respiratory failure

Answer 22

type 1- lung failure

type 2- pump failure

Question 23

is COPD a type 1 or type 2 resp failure

Answer 23

type 2

Question 24

what is FVC

Answer 24

spirometry test
forced vital capacity
forced expiration