12/12/2025
From cannula to Venturi—your quick guide to oxygen therapy
1️⃣ Nasal Cannula:- Soft tubes placed in the nose to deliver oxygen.
When used:-
👉For mild low oxygen levels
Patient can eat, drink, and talk while using it
Flow rate: 1–6 L/min
Oxygen delivered: 25–45%
Key points:
👉More comfortable
👉Low oxygen concentration
👉Can dry the nose → may need humidifier
2️⃣ Simple Face Mask:- A mask that covers the nose + mouth.
When used:-
👉When patient needs more oxygen than nasal cannula can provide
Flow rate: 6–10 L/min
Oxygen delivered: 35–60%
Key points:
👉Must be set to at least 6 L/min to prevent CO₂ rebreathing
👉Holes on sides allow carbon dioxide to escape
Cannot eat or drink with mask on
3️⃣ Non-Rebreather Mask (NRBM):- A mask with a reservoir bag and one-way valves.
When used:-
👉For very low oxygen levels
👉Emergency situations
👉Can deliver highest oxygen concentration without intubation
Flow rate: 10–15 L/min
Oxygen delivered: 80–100%
Key points:
👉Bag must stay partially inflated
👉One-way valves prevent room air frommixing → high oxygen
👉Best for severe hypoxia (e.g., trauma, shock)
4️⃣ Venturi Mask:- A mask with colored adapters (Venturi valves) that give exact oxygen percentages.
When used:
👉For patients who need precise oxygen control
👉Most important in COPD patients because too much O₂ can cause CO₂ retention
Flow rate: 2–15 L/min (depends on adapter)
Oxygen delivered: 24–60%
Key points:
👉MOST ACCURATE oxygen delivery device
👉Each color corresponds to a specific oxygen %
👉Common for COPD management
