Oxygen Titration

Question 1

List the indications for oxygen therapy.

Answer 1

i) SpO2 <90%
ii) p02 < 80 mmHg
iii) Reduce WOB
iv) Decrease myocardial work (acute MI)
v) surgical recovery

Question 2

Describe the difference between a low flow system and a high flow system.

Answer 2

Low flow supplements O2 to tidal volume and is the FiO2 varies slightly based on the patients tidal volume. High flow systems provide O2 for the entire tidal volume as it exceeds peak inspiratory flow.

Question 3

Describe the flow to FiO2 rule for nasal prongs.

Answer 3

1 L = 4% or 0.04 FiO2. Ex. 3LNP = 0.32.

Question 4

List which systems are high flow and which systems are low flow as well as their FiO2 capacity.

Answer 4

High Flow:
i) Venturi (0.35-0.6)
ii) OptiFlow (1.0 & PEEP) - not portable.
iii) Tracheostomy mask
iv) FLO2 (1.0) - portable.
Low Flow:
i) Nasal prongs (high flow 15L and low flow 6L)
ii) Oxymizer (15L/min)
iii) Simple Mask (0.35-0.5)
iv) Oxymask (0.24-0.9)
v) Ambu-bag/Manual Re-Breather (15L/min)
vi) Non-rebreather (8-15L/min).

Question 5

What effect will increase I:E ration have on FiO2 of a low flow device?

Answer 5

Increase.

Question 6

What effect will increase ventilation have on FiO2 of a low flow device?

Answer 6

Decrease - why pt needs more O2 to exercise.

Question 7

What harmful effects can arise from suboptimal oxygen titration?

Answer 7

i) pulmonary oxygen toxicity (ROS damage)
ii) respiratory failure (ex. COPD drive to breathe)
iii) bleomycin toxicity.

Question 8

When would you use a high flow device over a low flow device for oxygen titration?

Answer 8

Vulnerable population when you need to be exact - ex. CF, bleomycin.

Question 9

List three disadvantageous deficits associated with prolonged oxygen dependency.

Answer 9

i) POT (pulmonary oxygen toxicity) causing ROS damage
ii) fibrosis if on bleomycin
iii) mask clinical deteriotation
iv) absorption atelectasis (only O2 nd not enough N2 to act as air and keep alveoli inflated so they collaspe).