A study was undertaken to determine the incidence and type of laryngeal injury following long-term oral and nasal endotracheal intubation. Seventeen intensive care unit patients who were intubated from 5 to 9 days were studied. Seven patients had orotracheal intubation; 10 were intubated through the nose. Within 24 hours following extubation or tracheostomy. fiberoptic bronchoscopy was performed to evaluate the extent of laryngeal injury. A grading system used to quantify the degree of injury was based upon presence or absence of: vocal cord ulceration, vocal cord cratering and maceration, ulceration of the arytenoid or corniculate cartilages, ulceration of the glottic surface of the epiglottis, ulceration of the proximal posterior tracheal wall, supraglottic edema, and glottic closing abnormalities.
A standard lateral skull radiograph was performed on patients who had been nasally intubated. Anatomical measurements were ealculated from these radiographs in an attempt to correlate extreme variations from the normal with an increased incidence of laryngeal pathology. These measurements included calculation of palatal length ahd angulation and the position of the first cervical vertebra in an anterior-posterior position.
Although laryngeal damage was found following intubation by either route, our results showed that long-term oral endotracheal intubations were associated with injury approximately twice as often as were nasal intubations. We found no evidence that palatal length and angulation or position of the first cervical vertebra affected the incidence or type of laryngeal injury following nasotracheal intubation. We recommend nasal intubation over oral intubation in adult patients requiring long-term pulmonary support in whom there are no contraindications to nasotracheal intubation.