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Flashcards in resp phys 2 Deck (33)
1

what is atmospheric pressure

101 Kpa or 760 mmHg

2

what is the partial pressure of nitrogen

593

3

what is the partial pressure of oxygen

159

4

what is the partial pressure of CO2

0.29

5

what is Henry's Law

when a mixture of gasses is in contact with a liquid each will dissolve in proportion with its partial pressure

but the absolute amount of gas dissolved depends on its solubility. only applies to dissolved gas

the total amount of gas is that dissolved plus that chemically bound

6

what is the water vapour pressure in alveoli

48 mmHg

7

what is the O2 pressure in alveoli

104 mmHg

8

how will oedema affect diffusion

increases wall thickness

9

what is 2-3 bisphosphoglycerate

produced in metabolism

decreases the affinity of haemoglobin for oxygen

also temperature H+ CO2

modifies the 3d structure of Hb

10

how do you calculate the amount of O2 carried in the blood

total = conc HB x capacity of Hb x percentage saturation +amount dissolved in the plasma

11

what % of CO2 is carried in the plasma

7-10

12

what % of CO2 is bound to Hb

10-20 %

13

what is the Haldane effect

deoxygenation of Hb increases it affinity for CO2 and vice versa in the lungs

14

what enzyme forms carbonic acid

carbonic anhydrase

15

what is the Henderson hasslebach eqn

calculates the ph of blood

ph = pk + log (bicarbonate / co2)

16

where does most gas go in a normal lung

base

because the base changes volume more than the apex - more compliance
partly due to gravity

17

what do the bronchial arteries supply

lung parenchyma, airways smooth muscles, pulmonary arteries and veins and pleura

also warms inspired air

18

what is transmural pressure

balance between alveolar pressure and blood pressure

19

what is the normal distribution of blood flow

apex- low
base- high

blood pressure must be greater than alveolar pressure in order for blood to flow
if capillaries are closed then dead space

20

what happens in zone 1

cappilaries are closed

21

what happens in zone 2

cappileries are open in systole but not in diastole

22

what happens in zone 3

alveolar pressure is lower than arterial and venous pressure

23

what is the V/q at the base

0.6
more perfusion than ventilation

24

what is the v/q in the middle

1

25

what is the v/q at the apex

3 (more ventilation than perfusion)

26

what is hypoxic vasoconstriction

blood is diverted away from poorly ventilated areas

27

when does sputum production tend to be worse with COPD

morning

28

what is wheeze a sign of

obstruction

29

what defines obstructive airway disease

fev1/fvc

30

what is pKa

the ph at which 50% is unionised

31

what do metabolic acid base disturbances affect

the amount of protons and bicarbonate

32

what do respiratory disturbances affect

amount of CO2

33

what cells are toll like receptors found on

dendritic cells

also express pattern recognition receptors