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Flashcards in Atmosphere and respiration Deck (39)
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1

boyles law

V inversely proportional to P
associated with barotrauma

2

guy lussac law

volume const
P proportional to T

3

combined gas law

PV/T=k

4

ficks law

diffusion
high concentration to areas of low concentration
inversely proportional to thickness of membrane

5

daltons law

total pressure is equal to sum of the partial pressures
related to hypoxia

6

henrys law

more pressure, more gas can dissolve into a liquid directly proportional
related to decompression sickness

7

external respiration

occurs at lungs
between 12-20 breaths per minute at rest

Nose warms ,moistens & filters air

8

tidal volume

air inhaled & exhaled in normal breath
500ml

9

inspiratory reserve volume

extra can inhale above normal
3100ml

10

expiratory reserve volume

extra can exhale above normal
1200ml

11

residual volume

not all air breathed out. what's left in lungs
1200ml

12

total lung capacity

all volumes added

13

vital capacity

max can actually breath in or out
everything but residual

14

functional residual capacity

expiratory reserve + residual

15

inspiratory capacity

tidal volume + inspiratory reserve

16

altitude at which oxygen partial pressure of O2 drops to 1/2?

10000ft
drops to 55mmHg

17

altitude at which total pressure drops to 1/2?

18000ft
380mmHG

18

altitude at which total pressure drops to 3/4?

8000ft
543mmHg

19

altitude at which total pressure drops to 1/4?

36000ft
187mmHg

20

total pressure at MSL?

760mmHg

21

when oxygen partial pressure drops below 55mmHg...

alveoli no longer cope
above 10000ft
percentage of ox remains same but partial pressure decreases

22

haemoglobin saturation levels

SL- 97%
10000ft- 87%
20000ft- rapidly falls to 65%
saturation less than 90% can result in hypoxia

23

2 types of hypoxia

hypoxic- due to decrease in partial pressure of oxygen from increase in alt
anaemic- inability of blood to carry oxygen

24

what makes hypoxia worse?

smoking
high workload at altitude
unhealthy,alcohol, diet etc
higher alt= worse
exposure

25

hypoxia reaction threshold

GL- 7000ft
vision sensory affected as low as 5000ft
newer task/ memory affected
dark adaption affected

26

hypoxia disturbance threshold

7000-12000
increased blood pressure -
increased heart rate -
maintaining homeostasis

27

hypoxia critical threshold

12000-22000ft
homeostasis doesn't work
euphoria
cyanosis
fornication
dizziness
headache
impaired judgement
muscular impairment
hyperventilation
mental performance degraded to 12000ft
memory impaired 12000ft
confusion
grey out / tunnel vision
incapacitation
loss of consciousness
DEATH

28

TUC & EPT

time of useful consciousness
effective performance time- time you can perform flying duties effectively in reduced oxygen

29

TUC

20k- 30 min, mod activity- 5min
30k- 1-2min
35k- 30-90sec
40k- 15-20sec

halved for smokers

30

hyperventilation

lung ventilation in excess of bodies needs
too much CO2 removed from the blood
less carbonic acid - go into respiratory alkalosis
can lead to hypoxia - vasoconstricts vessels