Blind Nasotracheal Intubation
The blind nasotracheal technic is especially valuable for intubating spontaneously breathing patients with or without sedation, or under general anesthesia. It may be used in elective as well as selected emergent situations by the experienced operator, who may expect that more than 75% of patients will be intubated in less than 1 or 2 minutes.
Points of Technic
The patient should not suffer from a bleeding diathesis from, for example, thrombocytopenia or oral anticoagulants. Moderately severe epistaxis may result.The nasal mucosa should be gently prepared with phenylephrine, oxymetazolone (Afrin), or cocaine.
Local anesthesia should be considered, especially in the awake, sedated patient.
Sedation (or even general anesthesia) may be helpful. Intravenous agents, infused continuously, allow for controlled sedation that is independent of airway and breathing.
Place patient's head and neck in the "sniffing position" if not contraindicated.
It is a bit easier for right handed operators to use the right naris, though either may be used.
The same size tube that would have been selected for oral intubation is appropriate, especially in children.
Orient the ETT connector 90% to the plane of curvature of the ETT to provide tactile assistance in "aiming" the ETT.
Slowly, gently advance the ETT along the floor (inferior aspect) of the nose. Orient the tube to "aim" at the larynx. This would be slightly to the left for a tube entering the right naris. Listen for breath sounds.
Continue to advance the tube until one of the five response positions are reached. Decide which position has been reached, then make the appropriate response:
ADVANCE, DECIDE, RESPOND:
Position T (Trachea):
This is the goal position! Signs are: breath sound continue through tube, tube continues to advance, patient coughs through tube.
Response T: Secure tube. Auscultate breath sounds bilaterally. Confirm ETCO2.
Position A (Anterior):
Position A can be diagnosed by the following signs: breath sounds continue through the tube, the tube stops (unable to advance further), and the patient coughs (mostly through the tube).
Response A: Position A can almost always be converted directly to Position T by slight withdrawal and re-advance of tube while the patient's head and neck are gradually flexed toward the chin-on-chest positon.
Position L or R (Left or Right pyriform sinus): Signs are: breath sounds through tube STOP, tube stops (unable to advance), there is NO coughing. Occasionally the tube may be palpable on one side of the neck.
Response L or R: Position L or R can invariably be converted into one of the other three (T, A or E) by slight withdrawal (to the point where breath sounds through tube resume) and slow rotation (back toward midline) and re-advance.
Position E (Esophagus): Signs: breath sounds through tube STOP, tube continues to advance, there is NO coughing.
Response E: Position E can most often be converted to position T by withdrawing the tube until breath sounds through tube resume and then employing one or more of the following (separately or together):
1. Extend patient's head and re-advance.
2. Largely inflate cuff, advance tube until resistance is felt, maintain some advancing pressure on tube while cuff is slowly deflated.
3. Apply posterior pressure on the larynx and re-advance tube.
Most often, position T can be achieved. It only takes a minute or two to find out!