What is the maximum oxygen concentration delivery range for a nasal cannula?

The choice of 24-45% as the maximum oxygen concentration delivery range for a nasal cannula is based on the understanding of how this device functions and the levels of oxygen it can effectively deliver to patients. Nasal cannulas typically provide supplemental oxygen that is mixed with room air, allowing for a range of oxygen concentrations depending on the flow rate used.

At low flow rates, generally 1-6 liters per minute (L/min), the oxygen concentration can vary from approximately 24% to 45%. This range is influenced by factors such as the patient's breathing pattern and the flow rate of oxygen being administered. As the flow rate increases, the percentage of oxygen delivery can rise, but it typically does not exceed 45% with a standard nasal cannula setup. This makes it suitable for patients who require mild to moderate respiratory support without the need for more invasive oxygen delivery methods.

In comparison, higher ranges provided by the other options represent concentrations that would typically require more advanced devices, such as high-flow nasal cannulas or non-rebreather masks, which are designed for different clinical situations and provide higher concentrations of oxygen directly to the patient's airway.