What provides the patient with the highest level of oxygen without advanced airway procedures?

The nonrebreathing mask is the correct choice because it allows for the delivery of a higher concentration of oxygen to the patient compared to other options. This mask has a reservoir bag that fills with oxygen, and it typically provides an oxygen concentration of approximately 90-100% when applied correctly. The design includes one-way valves that prevent exhaled air from mixing with the oxygen being delivered, ensuring that the patient receives a concentrated flow of oxygen.

Using a nonrebreathing mask is particularly beneficial in situations where a patient is experiencing severe respiratory distress or hypoxia, as it maximizes the amount of oxygen available for inhalation. In contrast, a nasal cannula provides a lower concentration of oxygen, usually around 24% to 44%, which may not be sufficient for patients with significant oxygen needs. An oropharyngeal airway is mainly used to maintain an open airway and does not deliver oxygen itself. A suction catheter is designed for clearing obstructions in the airway and is not a means of providing oxygen.

Thus, in scenarios where maximizing oxygen delivery is vital, the nonrebreathing mask stands out as the most effective tool available without requiring advanced airway management techniques.