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What percentage of oxygen is typically delivered using a non-rebreather mask?

  1. 60% to 80%

  2. 70% to 90%

  3. 90% to 100%

  4. 100% to 110%

The correct answer is: 90% to 100%

A non-rebreather mask is designed to deliver high concentrations of oxygen to patients who are experiencing respiratory distress or other serious medical conditions requiring supplemental oxygen. It typically allows for the delivery of oxygen in the range of 90% to 100%. This mask has a reservoir bag that should remain inflated during inhalation, ensuring that the patient receives the highest possible concentration of oxygen. The functioning of a non-rebreather mask relies on a one-way valve which prevents the inhalation of room air and ensures that the patient breathes in mainly the oxygen from the reservoir. This design is particularly effective for patients who are critically ill or have conditions such as severe asthma, COPD exacerbations, or hypoxia, where every effort must be made to provide the maximum oxygen support available. Thus, the correct choice highlights the effectiveness of a non-rebreather mask in achieving a very high oxygen concentration for the patient.