With the flowmeter set at 6 L/min, the nasal cannula will deliver up to 44% oxygen.

With the flowmeter set at 6 L/min, the nasal cannula will deliver up to 44% oxygen.

• A. 28%
• B. 44%
• C. 60%
• D. 74%

Answer: (B)

A nasal cannula delivers oxygen by blending it with surrounding room air, so the FiO2 you achieve rises with higher flow but only up to a practical limit. The common rule of thumb is about 4% higher FiO2 for each liter per minute, starting around 24% at 1 L/min and reaching roughly 44% at 6 L/min. So at a flow of 6 L/min, the patient can receive about 44% oxygen. The other percentages would require different devices or higher FiO2 sources (for example, much higher FiO2 is possible with masks or high-flow systems, not with a standard nasal cannula).

A nasal cannula delivers oxygen by blending it with surrounding room air, so the FiO2 you achieve rises with higher flow but only up to a practical limit. The common rule of thumb is about 4% higher FiO2 for each liter per minute, starting around 24% at 1 L/min and reaching roughly 44% at 6 L/min. So at a flow of 6 L/min, the patient can receive about 44% oxygen. The other percentages would require different devices or higher FiO2 sources (for example, much higher FiO2 is possible with masks or high-flow systems, not with a standard nasal cannula).