Upper airway obstruction in the unconscious patient

Airway patency was studied in 80 anesthetized, spontaneously breathing patients, who received no muscle relaxants. With the neck flexed (chin towards chest) the airway was obstructed in all patients, both in the supine and prone positions, with and without an artificial oropharyngeal airway in place. With extension at the atlanto-occipital joint (chin up) in the supine position approximately 50% of the patients had an open airway. The other 50% required, in addition to extension of the neck, forward displacement of the mandible or the insertion of an oropharyngeal airway or both. Roentgenograms demonstrated that the tongue is pushed against the posterior pharyngeal wall when the neck is flexed and the mandible is not held forward. The incidence and degree of obstruction was similar in the prone and supine positions, with comparable positions of the head, neck and mandible. Submitted on December 19, 1958