What is the appropriate oxygen delivery device for a patient requiring FiO2 greater than 0.90?

A non-rebreather mask is the appropriate oxygen delivery device for a patient requiring a fraction of inspired oxygen (FiO2) greater than 0.90 because it is designed to deliver high concentrations of oxygen. This type of mask typically uses a reservoir bag that allows the patient to inhale oxygen directly from this bag, which fills from a continuous flow of oxygen supplied to the mask. The one-way valves on the mask prevent exhaled air from entering the bag, ensuring a higher concentration of oxygen during inhalation.

In scenarios where a patient needs significant supplemental oxygen—such as in cases of severe respiratory distress or acute hypoxemia—the non-rebreather mask plays a crucial role. It can deliver oxygen concentrations typically around 80-100%, making it suitable for emergencies or critical care situations where very high FiO2 is required.

Other devices, such as nasal cannulas, simple face masks, and Venturi masks, provide lower concentrations of oxygen and are not capable of achieving the high FiO2 levels associated with a non-rebreather mask. Nasal cannulas typically deliver up to about 50% oxygen, simple face masks can provide a range but are less effective than non-rebreathers, and Venturi masks are designed for