Nasopharyngeal Airway: Definition, Sizing, and Proper Measurement

A nasopharyngeal airway (NPA) is a flexible tube designed to maintain an open airway by passing through the nose and extending into the nasopharynx. It is commonly used in medical emergencies and situations where patients have difficulty maintaining a patent airway on their own. In this article, we will explore what a nasopharyngeal airway is, how to determine what size nasopharyngeal airway to use, and what to measure to properly insert a nasopharyngeal airway.

What Is a Nasopharyngeal Airway?

A nasopharyngeal airway, often called an "NPA" or "nasal trumpet," is a soft, flexible tube made from materials such as rubber or silicone. It is inserted into one of the nostrils and advanced into the nasal passage to help keep the airway open, especially in patients who may have a compromised airway due to trauma, unconsciousness, or other medical conditions that obstruct normal breathing. For information about actual nasopharyngeal airways such as size, material used in manufacturing, etc. you can visit websites of manufacturers such as that of Hangzhou Bever Medical Devices Co., Ltd., a professional nasopharyngeal airway producer with many years of experience.

Common Uses:

A. Emergency situations: An NPA is frequently used by first responders and medical professionals when a patient’s airway is at risk of closing due to injury, sedation, or altered levels of consciousness.

B. Alternative to oropharyngeal airways: In patients with intact gag reflexes or oral injuries that prevent the use of an oropharyngeal airway (OPA), an NPA is often the preferred option.

C. Continuous airway support: It can be used to facilitate ventilation in unconscious patients or those undergoing sedation.

The nasopharyngeal airway serves as a passage for airflow between the nose and the trachea, helping to prevent the tongue or soft tissues from collapsing and blocking the airway.

What Size Nasopharyngeal Airway Should You Use?

Choosing the correct size of a nasopharyngeal airway is critical for both safety and effectiveness. If the NPA is too small, it may not properly keep the airway open; if it’s too large, it could cause damage to the nasal passage or nasopharynx.

Sizing Nasopharyngeal Airways:

A. Nasopharyngeal airways come in various sizes, typically ranging from 12 French (smallest) to 36 French (largest), with the diameter of the tube measured in French units (1 French = 0.33 mm).

B. The most commonly used sizes for adults are 28, 30, and 32 French.

C. Pediatric sizes are smaller and typically range from 12 to 22 French.

When selecting the size, it’s essential to account for both the patient's age and size, as well as the size of their nasal passages. An appropriately sized NPA will fit snugly without causing discomfort or trauma.

What Should You Measure to Properly Insert a Nasopharyngeal Airway?

To ensure correct placement of the nasopharyngeal airway, accurate measurement is critical. Here’s what you need to measure to properly insert an NPA:

1) Length:

The length of the NPA is vital to ensuring it reaches the correct depth without causing damage.

The correct length can be estimated by measuring the distance from the tip of the patient's nose to their earlobe. This gives a good approximation of the distance the NPA needs to travel to reach the back of the nasopharynx.

2) Diameter:

The diameter of the NPA should allow it to pass easily through the nasal passage without causing discomfort or injury.

A general rule of thumb is to use a size that approximates the diameter of the patient’s smallest nostril.

3) Patient Comfort:

It's important to select a size that can be inserted without resistance. The NPA should slide smoothly into the nasal passage after applying a water-soluble lubricant to minimize friction.

Insertion of a Nasopharyngeal Airway

After selecting the appropriate size and confirming measurements, follow these steps for proper insertion:

1) Lubrication: Apply a generous amount of water-soluble lubricant (not petroleum-based) to the outside of the NPA to reduce friction and discomfort during insertion.

2) Angle and Insertion:

Gently insert the airway into the nostril that appears larger or clearer.

Advance the NPA following the natural curvature of the nasal passage, with the beveled tip facing toward the septum.

Continue advancing the NPA until the flange rests against the nostril. At this point, the airway should provide a clear path for breathing.

4) Monitoring:

Once the NPA is in place, regularly assess the patient's breathing and overall condition to ensure the airway remains open and the NPA is functioning correctly.

Final Remark

Inserting a nasopharyngeal airway is a procedure that requires careful selection and measurement of the device to ensure it provides adequate airway support without causing discomfort or injury. Understanding what a nasopharyngeal airway is, determining what size NPA is appropriate, and knowing what to measure before insertion are key steps in successful airway management. When done correctly, the NPA can be an invaluable tool for maintaining airway patency in patients with compromised breathing.