Nasopharyngeal airway

In medicine, a nasopharyngeal airway (NPA), nasal trumpet (because of its flared end), or nose hose, is a type of airway adjunct, a tube that is designed to be inserted through the nasal passage down into the posterior pharynx to secure an open airway. It was introduced by Hans Karl Wendl [de] in 1958.^[1] When a patient becomes unconscious, the muscles in the jaw commonly relax and can allow the tongue to slide back and obstruct the airway.^[2] This makes airway management necessary, and an NPA is one of the available tools. The purpose of the flared end is to prevent the device from becoming lost inside the patient's nose.^{[citation needed]}

Nasopharyngeal airway
Nasopharyngeal airway.
ICD-9-CM	96.01

Sizes

As with other catheters, NPAs are measured using the French catheter scale, but sizes are usually also quoted in millimeters.^[3][4] Typical sizes include: 6.5 mm/28FR, 7.0 mm/30FR, 7.5 mm/32FR, 8.0 mm/34FR, and 8.5 mm/36FR.^[5]

Indications and contraindications

These devices are used by emergency care professionals such as EMTs and paramedics in situations where an artificial form of airway maintenance is necessary, but tracheal intubation is impossible, inadvisable, or outside the practitioner's scope of practice. An NPA is often used in patients who are conscious or have an altered level of consciousness^[6] where an oropharyngeal airway would trigger the gag reflex.^[7][8] The use of an NPA is contraindicated when there is trauma to the face, especially the nose or if there is a suspected skull fracture.^[9]

Insertion

A nasopharyngeal airway inserted in the right nostril of a patient.

The correct size airway is chosen by measuring the device on the patient: the device should reach from the patient's nostril to the earlobe or the angle of the jaw.^[10] The outside of the tube is lubricated with a water-based lubricant so that it enters the nose more easily.^[5] The device is inserted until the flared end rests against the nostril.^[5]

References

1. Wendl H K. The story of the Wendl tube and its use. In: Schulte am Esch J, Goerig M (eds.) Proceedings of the Fourth International Symposium on the History of Anaesthesia. DrägerDruck, Lübeck, 1998, S. 531–534
2. James R. Sills (16 March 2015). The Comprehensive Respiratory Therapist Exam Review – E-Book: Entry and Advanced Levels. Elsevier Health Sciences. pp. 336–. ISBN 978-0-323-24188-5.
3. American Academy of Orthopaedic Surgeons (AAOS); Nancy L. Caroline (15 August 2017). Nancy Caroline's Emergency Care in the Streets. Jones & Bartlett Learning. pp. 801–. ISBN 978-1-284-10488-2.
4. Mick J. Sanders; Lawrence M. Lewis; Kim D. McKenna; Gary Quick (2012). Mosby's Paramedic Textbook. Jones & Bartlett Publishers. pp. 436–. ISBN 978-0-323-07275-5.
5. Michael Smith; Mike Smith; American Academy of Orthopaedic Surgeons (April 2006). ACLS for EMT-Basics. Jones & Bartlett Learning. pp. 17–. ISBN 978-0-7637-4395-6.
6. Atanelov, Zaza; Aina, Titilopemi; Amin, Bhavesh; Rebstock, Sarah E. (2022), "Nasopharyngeal Airway", StatPearls, Treasure Island (FL): StatPearls Publishing, PMID 30020592, retrieved 2022-09-14
7. Churchill Livingstone Elsevier (23 April 2012). Textbook of Paediatric Emergency Medicine, 2nd Ed. Bukupedia. pp. 476–. ISBN 978-0-7020-3368-1.^{[permanent dead link]}
8. Rachel K. Thomas; Elize Richards; Cathy Taylor (27 April 2015). Practical Medical Procedures at a Glance. John Wiley & Sons. pp. 59–. ISBN 978-1-118-63285-7.
9. Atanelov, Zaza; Aina, Titilopemi; Amin, Bhavesh; Rebstock, Sarah E. (2022), "Nasopharyngeal Airway", StatPearls, Treasure Island (FL): StatPearls Publishing, PMID 30020592, retrieved 2022-09-14
10. Daniel Limmer and Michael F. O'Keefe. 2005. Emergency Care 10th ed. Edward T. Dickinson, Ed. Pearson, Prentice Hall. Upper Saddle River, New Jersey. Page 147.