Oxygen Therapy

Question 1

When is additonaloxyfen needed

Answer 1

When 21% room air is inadequate
Resp disease - acute: pneumonia , oedema, asthma, ARDS
Chronic: COPD, fibrosis
Cardiac disease - arrhythmia, ischaemia, plum oedema
Trauma, neuro, liver renal

Question 2

What is suitable level when need some O2 and need lots of O2

Answer 2

Some 
Post op, early pneumonai
Nasal specs or simple face masks
Need for lots
Major trauma, sick patients 
Need to control the O2 conc - COPD - Venturi

Question 3

What is the max air we inspire in the breath cycle and why does this mean with oxygen supplement in methods we rarely get to 100% inspired O2

Answer 3

We can inspire 23-30lpm and if the oxygen supplied is max 15 then we will be entraining air into the mask unless it is a closed system and then still we will need air entrainment as the supply will not reach that inspired air flow rate

Question 4

What is a simple face mask
Type of mask
How does it work
What O2 can be given through it

Answer 4

Variable performance mask
Oxygen supply is between 4-10 lpm
There is extensive air entrainment the exhalation rots allow for the CO2 to leave the mask but also as we breath the o2 supplied does not match the lpm demands so we suck in air too meaning the percentage of O2 supplied cannot be 100%
These masks supply 30-40% o2

Question 5

What are nasal specs

Answer 5

They are very variable oxygen mask -
They are comfortable and well tolerated
Allow patients to eat
Widely available for domestic o2 use
Rely on breathing through the nose so if you breath through the mouth less o2 more air
Also mixing in the pharynx may occur
2-4L usually given can give up to 6 but this is unpleasant and other other option are available

Question 6

Approx conc through nasal spec 
1l
2l
3l
4l
5l
6l

Answer 6

25%
29%
33%
37%
41%
45%

Question 7

Hat is a reservoir non rebreath mask

Answer 7

It is a fixed performance mask
Oxygen flows into he bag during expiration
O2 from the bag with some mixed air during insp
One at valve that prevents expired air going into the bag
O2 - 80%
Short term only due to not being able to humidify so is a dry gas

Question 8

What are used for controlled ventilation

Answer 8

Venturi

Question 9

What do Venturi masks do

Answer 9

They entrain air to generate approx 30lpm gas flow rate at a predetermined concentration
Fixed inspired conc up to 30lpm inspflow rate
50:50 system if a dark green Venturi 60% is used it used 15l of oxygen that entrain 15l of air to ensure a 60% conc is obtained