A nasal cannula is a lightweight, flexible tube designed to deliver supplemental oxygen directly to the user’s nostrils. This common medical device consists of a plastic tube that splits into two short prongs intended to rest just inside the nasal passages. Its primary function is to increase the concentration of oxygen inhaled, thereby helping to improve the oxygen saturation levels in the blood for individuals with respiratory conditions. Using a nasal cannula is a simple, non-invasive method that supports breathing without obstructing the ability to speak or eat.
Connecting the Cannula and Preparing the Equipment
The equipment requires careful preparation to ensure safe and effective oxygen delivery. Begin by examining the entire length of the tubing for any kinks, twists, or damage that could impede the flow of oxygen. Any obstruction can restrict the prescribed flow rate and compromise the therapy.
The connection end of the tubing must be securely attached to the oxygen source, such as an oxygen concentrator or the regulator on a compressed gas tank. If a humidifier bottle is prescribed, the tubing connects to the bottle’s outlet, and the bottle is screwed onto the concentrator’s port. Ensure all connections are snug and airtight to prevent oxygen from leaking out.
If a flow meter is present, confirm it is set to the zero or off position before making the final connection. Once the cannula is securely connected, you can proceed to the application steps.
Proper Application and Setting the Flow Rate
Correct physical application ensures maximum oxygen flow and user comfort. Gently insert the two prongs into the nostrils, ensuring the curve points downward, following the natural shape of the nasal passage. The plastic ridge connecting the prongs should rest comfortably against the upper lip.
Next, loop the tubing over the top of each ear, similar to how one wears eyeglasses. Bring the two tubes together under the chin, where a plastic slide or bolo will be located. Adjust this slide so the tubing is secure but not tight, ensuring enough slack to comfortably fit two fingers between the tubing and the neck.
With the cannula correctly positioned, turn on the oxygen source and set the flow rate exactly to the number prescribed by the physician (L/min). Never adjust or change this prescribed flow rate without explicit instruction from a healthcare professional. Setting the flow rate too high can lead to nasal dryness, while setting it too low will fail to provide the required supplemental oxygen.
Managing Comfort and Preventing Skin Irritation
Long-term use of a nasal cannula can cause localized skin irritation due to constant pressure and the drying effect of oxygen flow. Nasal passages often become dry, especially at flow rates above four L/min, potentially leading to discomfort or minor nosebleeds. Using a humidifier bottle with the oxygen source is a common solution, as it adds moisture to the gas.
To address skin dryness directly, a water-based lubricant can be applied sparingly around the nostrils and lips. Petroleum-based products must be avoided as they pose a potential fire hazard with oxygen. Saline nasal sprays also help to keep the nasal mucosa moist and reduce irritation.
The tubing draped over the ears and cheeks can cause friction and pressure sores, so these areas should be checked regularly for redness or breakdown. Padding, such as specialized ear cushions or soft gauze wraps, can be placed around the tubing to relieve pressure. Securing the excess tubing to clothing with a clip also prevents the cannula from being pulled, reducing tension and the risk of accidental removal.
Routine Cleaning and Replacement Schedule
Maintaining the hygiene of the nasal cannula and associated equipment is necessary for effective therapy and infection prevention. The cannula should be cleaned routinely, generally once or twice a week, using mild liquid soap and warm water. After washing, rinse thoroughly to remove all soap residue and allow it to air dry completely before use.
If a humidifier bottle is used, replace the water daily with distilled water. Wash the bottle with warm soap and water every time it is refilled, and disinfect it with a mild vinegar and water solution at least weekly. The nasal cannula is disposable and must be replaced regularly (typically every two to four weeks), or immediately if the plastic becomes stiff, discolored, or cracked.