A 60-year-old man is found face down on the bathroom floor by family members who checked on him after not hearing from him in three days. On EMS arrival the patient is found to be tachycardic with a normal blood pressure, and has marked facial swelling with ulcers on his cheeks and lips, as well as a swollen, “rock hard” tongue that is immovable and protruding from his mouth.
He has snoring respirations, a room air oxygen saturation of 88%, a respiratory rate of eight, and doesn’t respond to verbal or painful stimuli. His family reports he’s a heavy drinker.
As the EMT begins bag valve mask (BVM) ventilation, the paramedic obtains a blood sugar of 134 mg/dl.
The EMT reports she can’t insert an oral pharyngeal airway because of the tongue obstruction.
Due to the patient’s altered mental status (his Glasgow Coma Scale score is 3) and disconcerting respiratory findings, the paramedic decides to intubate him. The paramedic attempts direct laryngoscopy with a Macintosh #3 blade, but massive tongue swelling will not allow the laryngoscope to fit in the patient’s mouth; so they paramedic elects to perform a blind nasotracheal (NT) intubation instead.
Nasotracheal intubation involves the passage of a tracheal tube through the nose, into the posterior pharynx, through the vocal cords and eventually into the trachea. It’s highly useful in selected circumstances, but can be a challenging procedure. There are no published studies that have examined the effectiveness or outcomes of NT intubation in the prehospital environment. However, one hospital study reported a success rate of 92% of blind NT intubations in a large series of emergency department patients, but success was highly provider-dependent.1
NT intubation may be performed if there is obstruction of the oropharynx due to clenched teeth, trauma or swelling.2,3 It’s often better tolerated than orotracheal intubation in the conscious or semiconscious patient. NT intubation may also be easier in patients with a limited mouth opening or restricted neck mobility. This procedure might also be easier than orotracheal intubation in the morbidly obese or other patients who are unable to lie flat, as it can be performed while the patient is seated.
NT intubation can be technically difficult and infrequently performed by most providers.2,3 The patient must be spontaneously breathing. It may cause damage to the nasal, pharyngeal and laryngeal structures. The tube may kink or clog more easily than an orally inserted endotracheal tube due to the sharp angle it’s required to take.
There may be a risk of introducing bacteria from the nasal passages and sinuses into the trachea. There could also be a risk of causing a sinus infection by blocking drainage of the sinus cavities. In a patient with a basilar skull fracture, the NT tube may inadvertently enter the cranial cavity.
- Spontaneously breathing patient who requires intubation;
- Obstruction of the oropharynx due to clenched teeth, trauma or swelling;
- Conscious or semiconscious patient who requires intubation;
- Limited neck mobility; and
- Inability to lie flat.
Contraindications & Cautions
- Suspected basilar skull fracture;
- Suspected nasal or facial fracture;
- Nasal obstruction;
- Expanding neck hematoma;
- Thrombolytic or anticoagulant use (caution);
- Patient combativeness if not controlled with sedation (caution); and
- Complete inability to open the mouth due to inability to clear vomitus or secretions (caution).
- Pre-oxygenate the patient by placing them on a non-rebreather mask at 15 liters per minute.
- If time permits and local protocols allow, apply a topical anesthetic such as 4% lidocaine mixed with a vasoconstrictor (0.25% phenylephrine or oxymetazoline) spray to the nasal mucosa. This will make tube insertion more comfortable for the patient and reduce bleeding. Some patients will also require IV analgesia or sedation.
- Position the patient in the “sniffing” position with the proximal neck slightly flexed and the head slightly extended.
- Inspect the nose and select the larger nostril as your passageway. Place a well-lubricated 32 French nasal trumpet into the nare.
- Assemble and check your equipment. Lubricate the distal end of a 7.0 or 7.5 cm NT tube. Check the cuff. Ensure that the plastic phlange on the proximal end is securely fastened to the NT tube. Gently place an airflow whistle device on the proximal end of the NT tube.
- Remove the nasal trumpet.
- Insert the NT tube into the nostril with the flanged end of the tube facing the nasal septum. Gently guide the tube in the anterior to posterior direction (the angle should be parallel to the roof of the mouth).
- As the tube is felt to drop into the posterior pharynx (at approximately 10-15 cm), listen closely to the patient’s breath sounds through the whistle device. Using the trigger found on the NT tube and gentle rotation, manipulate the tube until it’s positioned such that breath sounds are loudest.
- When the patient inspires, pass the NT tube through the vocal cords. The patient may gag or cough.
- Inflate the cuff with 5–10 mL of air.
- Confirm tube placement (listen for bilateral breath sounds, lack of gastric sounds, end-tidal CO2).
- Secure NT tube (typically around 28 cm at the nare for men and 26 cm for women).
- Ensure that the plastic phalange (that connects to the BVM) on the proximal end of the NT tube is securely connected to the tube. Consider taping it to the tube. There have been cases of this phalange becoming dislodged and the patient inhaling the NT tube.
- Position the patient for success. If possible, position the patient seated with the head in a neutral or sniffing position. The sniffing position may also be used in the supine patient.
- Use a controllable-tip NT tube (Endotrol). These tubes have a trigger on their proximal ends that can flex the distal tips. One study found that the controllable-tip NT tube enhanced first-attempt success with blind NT intubation. A study of paramedic-performed blind NT intubation reports success rates of 58% using standard ET tubes versus 72% success with directional-tip-control ET tubes. They are also made of softer plastic than standard tubes.
- Use an airflow whistle device (Beck Airway Airflow Monitor) to guide placement of the endotracheal tube.
- Have a backup plan. In every potentially difficult airway, always prepare for disaster. Be ready to perform mask ventilation, direct laryngoscopy and orotracheal intubation, placement of an extraglottic device, and cricothyroidotomy.
- Be careful not to force the tube if it’s not easily advancing because you could cause significant nasal trauma and bleeding, which may make securing the patient’s airway even more difficult.
- When inserting the NT tube, do not direct it cephalad (upward). The nasal cavity runs straight back toward the occiput.
- The NT tube may get “hung up” on a number of laryngeal structures. If this occurs, simply withdraw the tube 2 cm, reposition it by rotating it and gently pulling on the trigger device, and try again.
- If the tube passes posteriorly into the esophagus, the key is recognizing improper placement. Use all tools available to confirm placement including waveform capnography. If the patient can speak, the tube is not between the vocal cords. Once esophageal intubation is recognized, the tube can be withdrawn and the procedure repeated.
The patient was successfully intubated using the awake, blind nasal technique, and was then appropriately sedated and safely transported to the ED where he was found to have suffered a stroke.
1. Danzl DF, Thomas DM. Nasotracheal intubations in the emergency department. Crit Care Med. 1980;8(11):677–682.
2. McGill JW, Reardon RF. Tracheal intubation. In Roberts JR (Ed.), Clinical Procedures in Emergency Medicine, 5th edition. Saunders: Philadelphia, Pa., pp. 58–98, 2009.
3. Levitan R. (2011.) Blind nasal intubation techniques.Airway Cam Practical Airway Management Portal. Retrieved on June 10, 2013, from www.airwaycam.com/blind-intubation-techniques.html.
4. Hooker EA, Hagan S, Coleman R, et al. Directional-tip endotracheal tubes for blind nasotracheal intubation. Acad Emerg Med. 1996;3(6):586–589.
5. O’Connor RE, Megargel RE, Schnyder ME, et al. Paramedic success rate for blind nasotracheal intubation is improved with the use of an endotracheal tube with directional tip control. Ann Emerg Med. 2000;36(4):328–332.