Basic discussion on oxygen delivery devices and their indications

1. OXYGEN
DELIVERY
SYSTEMS
THE BASICS
Dr Avinash A Nair
Assistant Professor
Department of Respiratory
Medicine
CMC , Vellore

2. OXYGEN THERAPY
• Oxygen is a drug
• It is the administration of oxygen at concentrations greater than
ambient air
• Used in acute and chronic care

3. WHEN DO YOU GIVE HIGH FLOW O2 TO
A PATIENT?
A. Acute exacerbation of asthma
B. Cardiac arrest
C. Cyanide poisoning
D. Major trauma
E. Anaphylaxis

4. CONTROLLED VERSUS
UNCONTROLLED

5. UNCONTROLLED OXYGEN THERAPY
When concern
is to raise pAO2
to the maximum
No concern of
CO2 retention
or fall in pH

6. UNCONTROLLED
SPO2 94-98%
Cardiac arrest
Cyanide poisoning
Major trauma
Anaphylaxis

7. CONTROLLE
D OXYGEN
THERAPY
(88-92%)
Acute exacerbation of COPD
Exacerbation of cystic fibrosis
Ventilatory failure in patients
with OHS
Ventilatory failure in patients
with NM failure , scoliosis

8. SOME CONTROL !!!!
(NEVER 100%)
• Adverse outcomes
• MI
• Sickle cell crisis
• Obstetric emergencies
• Other poisonings (other
than CO, cyanide)
• Metabolic acidosis
• Stable post cardiac arrest

9. WHAT
HAPPENS
IF I GIVE
MORE
OXYGEN??
Reduction in respiratory
drive
Reduces hypoxic
vasoconstriction
Free radical injury (paraquat
poisoning and Bleomycin)

10. DEVICES
• Low flow
devices
• High flow
devices

11. LOW FLOW DEVICES
• Nasal cannulas
• Simple face mask
• Partial rebreathing and non-rebreathing masks

12. NASAL
CANNULAE

13. NASAL CANNULAE – A SMILING PATIENT
• Flow upto 4l/min
• An oxygen flow >6 L·min−1 should be avoided as it can dry the
nasal mucosa and can disturb sleeping patterns
• Can talk and eat while receiving oxygen, and it is easy to use

14. SIMPLE FACE MASK ( SIMPLE!!!)
• Can deliver 5 and 10 L·min−1 (35–55% FIO2)
• Lower than 4l flow rebreath CO2 via exhalation ports
• Claustrophobic
• Unable to eat or talk freely

16. NON-REBREATHER MASK
• Low-flow device with high FIO2
• Reservoir bag (∼1000 mL) to deliver a higher concentration of
oxygen
• One-way valve between the mask and the reservoir bag prevents
the patient from inhaling expired air
• Risk of carbon dioxide retention and aspiration in case of vomiting
• A flow less than 6l/min – no purpose
• Less than 10l/min usually bag collapses

17. TTOC – TRANSTRACHEAL OXYGEN
CATHETERS
• Bypasses anatomical dead space
• 0.5 and 4 Lmin−1
• Less O2 waste
• Mildly invasive
• Good for palliation

19. HIGH FLOW OXYGEN DEVICES

20. • Venturi mask
• High flow nasal cannulae

21. VENTURI MASK
• High-flow device that allows precise measurement of FIO2
delivered
• The oxygen flow exceeds the patient's peak expiratory flow.
Therefore, it is unlikely for the patient to breathe in air from the
room
• Useful especially when accurate delivery is crucial e.g., COPD

23. HIGH-FLOW
NASAL CANNULA
• Flow generator can provide gas
flow up to 60 L·min−1
• Heated humidified oxygen is
delivered to a wide-bore nasal
prong
• Improve functional residual
capacity and muco ciliary
clearance of secretions, and
thereby they reduce the work of
breathing

24. Oxygen delivery devices Flow rate (litre/min) Approximate FiO2
Nasal cannula 1-6 0.24-0.44
Simple face mask 5-8 0.40-0.60
Partial rebreathing mask 6-10 0.60-0.80
Non rebreathing mask 10-15 0.90-1.00
Venturi mask 2-15 0.24-0.60