A Nasopharyngeal Airway (NPA), often referred to as a nasal trumpet, is a soft, flexible tube inserted through a patient’s nostril and into the pharynx. It maintains a clear passage for air, bypassing obstructions caused by the tongue or soft tissues relaxing against the back of the throat. It is commonly used in emergency settings when a patient’s reduced level of consciousness places them at risk for airway compromise. Unlike an oral airway, the NPA can often be tolerated by semi-conscious patients who still possess an intact gag reflex.
Selecting the Correct Size and Preparing the Patient
Proper selection of the NPA size is paramount to ensure both effectiveness and patient safety. The correct length is estimated by measuring the distance from the tip of the patient’s nose to the tragus of their ear. This measurement ensures the tip of the airway will rest correctly in the pharynx without being so long that it irritates the larynx or triggers the gag reflex. An NPA that is too short will not adequately maintain airway patency, while one that is too long can potentially cause vomiting and aspiration.
The diameter of the airway, typically measured in French sizes, should also be carefully considered to allow for smooth passage. A general guideline suggests selecting a diameter similar to the patient’s smallest nostril. Before insertion, the entire barrel of the NPA must be coated with a water-soluble lubricant. This minimizes friction and reduces the risk of mucosal trauma and bleeding inside the nasal passage.
Patient positioning facilitates easier placement. Whenever possible, the patient should be placed in the “sniffing position,” which involves slight neck flexion and head extension. This alignment straightens the airway axes, creating a more direct path for the NPA to follow. If a cervical spine injury is suspected, a modified jaw-thrust maneuver is used to open the airway instead of head movement.
Step-by-Step Insertion Technique
With the appropriate size selected and the airway well-lubricated, the insertion process can begin. The preferred nostril for insertion is typically the one that appears larger or less obstructed. The bevel, the slanted opening at the tip of the tube, should be oriented toward the nasal septum, the wall that divides the nostrils.
The NPA is inserted gently, following the natural curvature of the nasal passage and the floor of the nasopharynx. This means directing the tube almost straight back, perpendicular to the face. Directing the tube upward is a common error that can cause significant trauma to the nasal turbinates. Insertion must be a steady, gentle motion, avoiding any forceful advancement.
If resistance is encountered, a slight rotational movement of the NPA can sometimes help navigate past minor anatomical obstacles. If significant resistance persists, the device should be immediately withdrawn, and insertion should be attempted in the other nostril. Once the tube is fully inserted, the flange (the wide rim) should rest flush against the external opening of the nostril.
After placement, the patency of the airway must be verified by listening for the movement of air through the tube. The flange of the NPA should then be secured to the patient’s face to prevent accidental dislodgement. The NPA must be continuously monitored to ensure it remains open and is not blocked by secretions.
Recognizing When to Use an NPA and Absolute Precautions
The Nasopharyngeal Airway is indicated for patients who require an adjunct to maintain an open airway but are unable to tolerate an oral airway due to an intact gag reflex. This commonly includes semi-conscious patients with a reduced level of alertness, such as those following a seizure or a drug overdose. It is a temporary measure until the patient’s condition improves or a more definitive airway can be secured.
There are specific patient conditions where the use of an NPA is strictly prohibited due to the risk of severe complications. The absolute contraindication is the presence or suspicion of a basilar skull fracture or severe midface trauma. In this scenario, the tube could pass through a fractured cribriform plate and enter the cranial cavity, causing catastrophic injury.
Other serious contraindications include significant nasal trauma or active bleeding disorders, as the insertion process can cause or worsen epistaxis (nosebleeds). This procedure must only be performed by trained medical professionals, such as paramedics, nurses, or physicians, who can accurately assess the patient’s condition and manage potential complications.