Which type of mask is designed to deliver medium to high concentrations of oxygen?

The type of mask that is designed to deliver medium to high concentrations of oxygen is the nonrebreather mask. This mask is equipped with a reservoir bag and has specially designed valves that prevent exhaled air from being inhaled again, allowing for high concentrations of oxygen to be delivered to the patient.

When a patient inhales, fresh oxygen from the reservoir bag is drawn in; this setup can deliver oxygen concentrations of 60% to 100%, making it suitable for patients needing significant respiratory support, such as those experiencing conditions like severe hypoxia.

While the rebreather mask might seem like a possible option due to the ability to recycle some exhaled air, it is generally not designed for the same high concentration delivery since it allows mixing of exhaled air with the incoming oxygen. The simple mask delivers lower concentrations, and the partial nonrebreather mask, despite retaining some carbon dioxide in the exhaled breath, does not achieve the same effectiveness in oxygen delivery as the nonrebreather mask. Thus, the nonrebreather mask is the most effective for providing high concentrations of oxygen.