Which oxygen delivery method is appropriate for noninvasive administration of high FiO2?

• A. Nonrebreather mask
• B. Nasal cannula
• C. Venturi mask
• D. Simple face mask

Answer: (B)

Delivering a high fraction of inspired oxygen without an invasive airway means choosing a device that can concentrate oxygen while the patient breathes on their own and remains comfortable enough for the duration of treatment. A nasal cannula fits this goal well because you can raise the FiO2 by increasing the flow, and it’s typically well tolerated for extended periods. It also allows easy adjustment and continuous monitoring of the patient’s status as needs change.

Other options have limitations for high FiO2 delivery. A simple face mask often provides variable FiO2 and depends on a good seal, which can be uncomfortable and less precise. A Venturi mask can deliver a fixed, precise FiO2 but is less adaptable and can be less comfortable for patients. A nonrebreather mask can deliver very high FiO2, but it requires a snug seal and a reservoir, which can be cumbersome and less comfortable for ongoing use.

Thus, for noninvasive administration of high FiO2 with good tolerance and titratability, the nasal cannula is a practical choice among these options. (In clinical practice, high-flow nasal therapy represents an advanced form of this approach to achieve higher and more stable FiO2.)