Methods of Oxygen Delivery 

Low-Flow Oxygen Devices 

Nasal Cannula: 
– Flow: 1–5 L/min 
– FiO₂: 24–40% 
– Indications: Mild hypoxemia 
 
Simple Face Mask: 
– Flow: 2–10 L/min 
– FiO₂: 24–60% 
 
Non-Rebreather Mask: 
– Flow: 10–15 L/min 
– FiO₂: 60–90% 
– Used in severe hypoxemia 
 
High-Flow Oxygen Devices 

Venturi Mask: 
– Fixed FiO₂ (24–60%) 
– Preferred in COPD/conditions where establishing exact Oxygen delivery needed 
 
High-Flow Nasal Cannula (HFNC): 
– Flow up to 60 L/min 
– FiO₂ 21–100% 
 
Positive Pressure Devices 

CPAP: 
– Used in pulmonary oedema, OSA 
 
BiPAP: 
– Used in COPD exacerbations, hypercapnia 
 
Invasive Oxygen Delivery 

Endotracheal Intubation and Mechanical Ventilation: 
– FiO₂ up to 100% 
– Used in respiratory failure 
 
Key Points: 
– COPD: Venturi mask 
– Pulmonary oedema: CPAP 
– Hypercapnia: BiPAP 
– Severe hypoxemia: NRB