Which device provides the highest oxygen concentration?

Which device provides the highest oxygen concentration?

• A. Nasal cannula
• B. Venturi mask
• C. Simple face mask
• D. Non-rebreather mask

Answer: (D)

The device that can deliver the highest oxygen concentration is the one with a reservoir and one-way valves. It stores oxygen in a bag and channels inhaled air from that bag while preventing exhaled air from diluting it, so with the flow set high enough and the bag staying inflated, the inhaled gas can be very rich in oxygen—approaching 100% in ideal conditions. Nasal cannulas provide the lowest to moderate oxygen concentration, increasing with flow up to about the mid-40s percent, but they continuously mix with room air as you breathe. Venturi masks deliver a precise but limited range of oxygen concentrations, typically around 24–50%, depending on the adapter. Simple face masks offer more than a cannula but still mix with room air, usually achieving roughly 40–60% oxygen. So, when the goal is the highest possible oxygen concentration, the non-rebreather mask is the best choice, provided it fits well and the oxygen flow is sufficient to keep the reservoir inflated.

The device that can deliver the highest oxygen concentration is the one with a reservoir and one-way valves. It stores oxygen in a bag and channels inhaled air from that bag while preventing exhaled air from diluting it, so with the flow set high enough and the bag staying inflated, the inhaled gas can be very rich in oxygen—approaching 100% in ideal conditions.

Nasal cannulas provide the lowest to moderate oxygen concentration, increasing with flow up to about the mid-40s percent, but they continuously mix with room air as you breathe. Venturi masks deliver a precise but limited range of oxygen concentrations, typically around 24–50%, depending on the adapter. Simple face masks offer more than a cannula but still mix with room air, usually achieving roughly 40–60% oxygen.

So, when the goal is the highest possible oxygen concentration, the non-rebreather mask is the best choice, provided it fits well and the oxygen flow is sufficient to keep the reservoir inflated.