What is a Nasal Trumpet?
A nasopharyngeal airway (NPA), commonly called a nasal trumpet because of its flared end, is a soft, flexible tube made of medical-grade material [1.2.3, 1.2.5]. It is designed to be inserted through a patient's nostril into the posterior pharynx [1.2.5]. The primary function of this airway adjunct is to bypass upper airway obstruction at the level of the tongue or soft palate, thereby creating a clear channel for air to flow to the lungs [1.2.4, 1.10.4]. When a person becomes unconscious or semiconscious, their jaw muscles can relax, allowing the tongue to fall back and block the airway [1.2.5]. The nasal trumpet mechanically stents this space open, ensuring the patient can continue to breathe spontaneously or be ventilated effectively [1.9.1]. The flared end prevents the device from being accidentally lost inside the patient's nasal passage [1.2.5].
Core Indications: When is a Nasal Trumpet Necessary?
Healthcare providers choose to use a nasal trumpet in specific clinical situations where other airway devices may be less suitable. The main advantage of an NPA is its tolerability in patients who are conscious or semiconscious and still have an intact gag reflex [1.7.5, 1.10.1]. An oropharyngeal airway (OPA) in such a patient would likely trigger gagging, vomiting, or laryngospasm [1.7.2].
Key indications for using a nasal trumpet include:
- Conscious or Semiconscious Patients: The NPA is the preferred basic airway adjunct for patients who are not deeply unconscious and can't tolerate an OPA [1.2.1].
- Oral Trauma or Obstruction: It's invaluable when the patient's mouth is difficult to access. This includes conditions like trismus (lockjaw), angioedema, significant facial injuries, or if the jaw is wired shut [1.2.1, 1.2.3].
- Facilitating Suctioning: For patients who need frequent nasotracheal suctioning to clear secretions, an NPA provides a clear and less traumatic path [1.2.3, 1.3.4].
- Oral or Maxillofacial Surgery: During certain dental and facial surgeries, an NPA allows anesthesiologists to manage the airway without obstructing the surgical field [1.2.1, 1.9.2]. It can also be used to dilate the nasal passage before nasotracheal intubation, which has been shown to ease tube insertion and reduce bleeding [1.9.4].
- Alternative to CPAP: In some cases of obstructive sleep apnea (OSA), a nasal trumpet can be used as a long-term treatment, especially for patients who cannot tolerate continuous positive airway pressure (CPAP) therapy [1.8.1]. Studies have shown it can significantly reduce the apnea-hypopnea index (AHI) by stenting the airway open during sleep [1.8.4].
Nasal Trumpet (NPA) vs. Oropharyngeal Airway (OPA)
A crucial skill in airway management is knowing which adjunct to use. The choice between an NPA and an OPA depends largely on the patient's level of consciousness and anatomy [1.7.2].
| Feature | Nasal Trumpet (NPA) | Oropharyngeal Airway (OPA) |
|---|---|---|
| Insertion Route | Nasal cavity [1.2.5] | Oral cavity (mouth) [1.7.5] |
| Patient Consciousness | Tolerated in conscious, semiconscious, and unconscious patients [1.2.2] | Only for deeply unconscious patients without a gag reflex [1.7.5] |
| Gag Reflex | Does not typically stimulate the gag reflex [1.2.1] | Will stimulate a gag reflex in conscious or semiconscious patients [1.7.2] |
| Key Indication | Patient has an intact gag reflex or oral access is limited [1.2.1, 1.7.5] | Patient is unresponsive and has no gag reflex [1.2.2] |
| Contraindications | Suspected basilar skull fracture, severe facial/nasal trauma [1.6.1] | Conscious patient, foreign body airway obstruction [1.7.2] |
Proper Sizing and Insertion Technique
Correct sizing and insertion are critical to ensure the NPA is effective and to minimize complications like bleeding or tissue damage [1.6.2].
Sizing the Airway
There are two primary methods to estimate the correct length:
- Nose to Tragus: Measure the distance from the tip of the patient's nose to the tragus of the ear [1.3.3, 1.4.1]. The airway should extend this length.
- Nose to Mandible: Place the airway at the nasal opening and orient it toward the angle of the mandible. If it extends past the mandible it is too long; if it doesn't reach, it's too short [1.5.1].
The diameter should be the largest that can fit comfortably in the nostril without causing the skin to blanch [1.6.3]. For adults, sizes typically range from 6.0 mm to 8.0 mm [1.5.3].
Step-by-Step Insertion
- Prepare: Explain the procedure if the patient is conscious. Ensure suction is ready. Apply a water-soluble lubricant to the outside of the NPA to ease insertion [1.4.4, 1.4.5]. Some protocols suggest a vasoconstrictor nasal spray to reduce bleeding risk [1.9.2].
- Position: If no cervical spine injury is suspected, place the patient in the "sniffing position" [1.4.1]. If a spinal injury is possible, use the jaw-thrust maneuver without tilting the head [1.2.1].
- Insert: The beveled tip should face the nasal septum. Gently insert the airway into the nostril (the right is often preferred as it's typically larger) parallel to the floor of the nasal cavity, not upwards [1.4.1, 1.4.5].
- Advance: Use a gentle, steady pressure. If resistance is met, a slight rotation may help. Do not force the airway [1.4.1]. If it still won't pass, attempt insertion in the other nostril [1.4.5].
- Confirm: Advance the tube until the flared flange rests against the nostril opening [1.4.1]. Check for air movement and assess for improved breathing. The tip should ideally rest just above the epiglottis [1.6.3].
Potential Complications and Contraindications
While highly effective, NPAs are not without risks.
Contraindications
The most significant contraindication is a known or suspected basilar skull fracture [1.6.1]. Signs of this include cerebrospinal fluid (CSF) leakage from the nose or ears or "Battle's sign" (bruising behind the ears) [1.3.2]. In such cases, there is a risk of the tube passing through the fractured cribriform plate into the cranial cavity [1.6.1]. Other contraindications include severe facial or nasal fractures, coagulopathy (bleeding disorders), and recent nasal surgery [1.2.3, 1.6.3].
Complications
- Epistaxis (Nosebleed): This is the most common complication, caused by damage to the nasal mucosa [1.6.3]. Proper lubrication and gentle technique can minimize this risk.
- Incorrect Sizing: An NPA that is too long can enter the esophagus, leading to gastric distension during ventilation, or stimulate the larynx, causing laryngospasm [1.6.1]. One that is too short will be ineffective.
- Tissue Trauma: Forcing the device can cause damage to nasal turbinates or create a false passage through submucosal tissue [1.6.1, 1.6.3].
- Dislodgement: Rarely, an unsecured NPA can be aspirated into the lower airway, a serious complication requiring radiological imaging to diagnose [1.6.4].
Conclusion
So, why would you use a nasal trumpet? It is an essential, minimally invasive tool for airway management, particularly distinguished by its utility in patients who are not fully unconscious [1.10.4]. Its ability to bypass the tongue and maintain a patent airway without triggering a gag reflex makes it indispensable in emergency medicine, anesthesia, and critical care [1.2.1]. When used with proper sizing, technique, and a clear understanding of its indications and contraindications, the nasopharyngeal airway is a fast and effective life-saving intervention. For more information from an authoritative source, see StatPearls from the NCBI bookshelf.
