What is the primary function of a nasal cannula?

The primary function of a nasal cannula is indeed to provide low concentrations of oxygen. This device is widely used in medical settings to deliver supplemental oxygen to patients who need it but may not require high concentrations.

Nasal cannulas are designed to deliver oxygen directly into the nasal passages, allowing patients to breathe the oxygen in naturally while still being able to talk, eat, or move without much impediment. This method is particularly helpful for patients with mild to moderate respiratory distress or conditions like COPD (chronic obstructive pulmonary disease), where high concentrations of oxygen might not be necessary and can even be harmful.

Other methods of oxygen delivery, such as face masks, are employed when higher concentrations are required, which differentiates the nasal cannula's role. Furthermore, while it can be used in conscious patients, it is not effective for those who are unconscious or unable to maintain their own airway, which is where other devices would be more appropriate. Similarly, monitoring blood oxygen levels would involve different tools, such as pulse oximeters, rather than the nasal cannula itself.