A nasal cannula is a common medical device designed to deliver supplemental oxygen directly into the nostrils for individuals who require respiratory support. This flexible tubing and prong system provides a less restrictive alternative to a face mask, allowing the user to speak, eat, and drink more easily while receiving therapy. Proper placement is essential for effective oxygen delivery and user comfort. Understanding the correct orientation of the small prongs is the first step in successful oxygen use.
The Correct Direction of Nasal Cannula Prongs
The small, flexible tubes on the cannula, known as prongs, are typically curved to match the natural shape of the nasal passage. For the device to work correctly, the prongs must be inserted with this curve pointing downward toward the upper lip and the floor of the nose. This orientation maximizes therapeutic benefit and minimizes irritation.
When the prongs curve downward, the flow of oxygen is directed toward the back of the throat, or the nasopharynx, which is the intended target for gas exchange. If the prongs are mistakenly placed pointing upward, the oxygen is directed into the upper, more sensitive tissues of the nasal cavity. This incorrect placement can lead to discomfort, dryness, and irritation.
Many cannulas feature a small, flat tab located just below the prongs, which rests flat against the skin of the upper lip, serving as a visual cue for the correct downward orientation. Correct sizing is also a factor; the prongs should sit comfortably inside the nostrils without completely blocking them.
Step-by-Step Insertion and Secure Fitting
Once the prongs are correctly oriented, they should be gently inserted into the nostrils so they sit just inside the opening. The tubing extending from the prongs is then secured by looping it over both ears. This method holds the prongs in place without excessive pressure on the nose or face.
The two lengths of tubing meet below the chin, where a plastic adjuster (cinch or bolo) is used to secure the fit. This slide should be pushed up toward the throat until the tubing is snug against the neck and jawline. The fit must be secure enough to prevent slipping but loose enough to avoid skin indentations or discomfort.
It should be possible to comfortably fit two fingers between the tubing and the underside of the chin. An alternative placement method involves running the tubing down the back of the neck and using the slide to cinch the fit at the back of the head. Regardless of the route, the tubing should be managed to prevent kinks and ensure an uninterrupted flow of oxygen.
Troubleshooting Comfort and Flow Issues
Skin irritation is a common issue, often occurring behind the ears or beneath the nostrils. The constant friction from the tubing can cause tenderness or pressure sores. To mitigate this, protective accessories like soft fabric tubing wraps or padding can be placed behind the ears.
Dryness and crusting inside the nose result from the continuous flow of dry oxygen. When oxygen flow rates exceed 4 liters per minute, a humidifier bottle is often attached to the oxygen source to add moisture to the delivered gas, which reduces nasal irritation. If a humidifier is not used, a water-based nasal saline spray can help maintain moisture within the nasal passages.
Regularly check the tubing for kinks or blockages, as these can severely restrict or stop the prescribed oxygen flow. The tubing should be inspected for furniture or body weight pressing down on it, which could compromise oxygen delivery. Replacing the cannula every two to four weeks helps ensure the prongs remain soft and flexible, maintaining user comfort and effective therapy.