What oxygen delivery system most reliably delivers a high concentration of inspired oxygen to a 7-year-old child?

A nonrebreathing face mask is the most effective option for delivering a high concentration of inspired oxygen, especially in emergency situations such as respiratory distress or failure. This type of mask is designed to allow the patient to inhale a combination of oxygen from an external source and to not re-inhale any carbon dioxide they exhale. The mask features a reservoir bag that fills with oxygen, which is delivered at high flow rates. Additionally, one-way valves prevent the backflow of air from the mask, ensuring that the patient receives a concentrated supply of oxygen, often delivering approximately 80-90% oxygen concentration.

In contrast, other oxygen delivery systems do not achieve this level of oxygen concentration as effectively. A simple face mask may provide higher oxygen levels than a nasal cannula, but typically delivers around 40-60% oxygen and lacks the reservoir component that characterizes the nonrebreathing mask. A nasal cannula is suited for lower flow rates and is generally used to deliver 24-44% oxygen, depending on the flow rate, which is insufficient for cases that require high concentrations. The Venturi mask utilizes different ports to deliver precise concentrations of oxygen but generally provides lower concentrations compared to a nonrebreathing mask, making it less reliable