NREMT Paramedic Practice

What is the minimum flow rate for a non-rebreather mask to function effectively?

1. 5-10 L/min

2. 10-15 L/min or higher

3. 1-5 L/min

4. 2-8 L/min

The correct answer is: 10-15 L/min or higher

A non-rebreather mask is an essential tool in prehospital care, particularly for patients who are in respiratory distress or require a high concentration of oxygen. The effectiveness of a non-rebreather mask hinges significantly on the flow rate of oxygen delivered. The minimum flow rate for a non-rebreather mask to function effectively is recommended to be 10-15 liters per minute or higher. This flow rate ensures that the reservoir bag, which is a crucial component of the mask, remains inflated during inhalation. When the bag is inflated, it provides a substantial volume of oxygen for the patient to inhale, helping to achieve a higher concentration of oxygen (typically around 90% or more) when delivered to the patient. If the flow rate is set lower than this, there is a risk that the reservoir bag will collapse during inhalation, which compromises the oxygen delivery. Inadequate flow can lead to a mix of exhaled carbon dioxide and ambient air in the mask, significantly reducing the mask's effectiveness in providing high-flow oxygen therapy. Therefore, maintaining a flow rate of 10-15 L/min is crucial for optimal use of a non-rebreather mask in emergency situations.