Their contemporary use is commonly limited to the relief of upper-airway obstruction in two circumstances:
1) after extubation of the trachea in a spontaneously breathing patient, or
2) during mask ventilation when an oral airway (and jaw lift) has failed to produce an acceptable airway.
It has not been previously reported that a standard, single-lumen nasopharyngeal airway could be used effectively to deliver positive-pressure ventilation as a rescue device in the cannot-ventilate/cannot-intubate scenario.
Another important use of the nasal trumpet is what is called the modified Nasal trumpets method or the MNT.
In MNT The materials used consisted of a 30 or 32 French soft nasal airway (trumpet) and a 7.5- or 8-mm ETT connector. The ETT connector was inserted into the flared or proximal end of the nasal airway.
The mating of the ETT connector to the nasal trumpet can occur quickly.Then you use this "Supraglottic"tool to deliver tidal volumes ,but you have to close the next nostril and mouth cavity. see the photo
The MNT has been used in many cases of difficult airway Scenarios and in difficult to ventilate and difficult intubate night mares.it was of big benifits and saved many lives.
Because it is a supraglotticMNT maneuver requires relaxed or open cords. Initial inability to ventilate has been corrected by the administration of a muscle relaxant, but one must be confident that such inability to ventilate is, in fact, a supraglottic problem. The technique is not suitable for a patient with occluded or compressed nasal passages.
Gastric distention, regurgitation, or aspiration has not occurred using the MNT maneuver. If desired, a nasogastric tube can be passed down the unused nostril while ventilation proceeds. The ability to ventilate continuously while performing the fiber-optic intubation is another valuable feature of the technique.
The MNT maneuver can be a valuable addition to our airway armament for the following reasons:
a)mask fit is eliminated as a source of inadequate ventilation,
b) mouth opening and neck manipulation are not required,
c) the technique requires minimal experience, skill, and equipment, and
d) the technique succeeds in establishing an airway after other conventional methods have failed.