The histopathology of the larynx in the neonate following endotracheal intubation.

Subglottic stenosis is the most common serious complication of endotracheal intubation in the neonate with an incidence of between 1-8 per cent. While considered a complication of traumatic injury to the larynx and possibly associated with prolonged intubation, the pathogenesis is poorly understood and the pathology has not been described in detail. The nature of intubation induced injury has been investigated by examining step-sections of 43 larynges removed from neonates post-mortem who had been intubated for periods ranging from 10 min to 12 weeks. Focal ulceration was identified in the supraglottis and the anterior glottis. Similar injury was seen in the posterior glottis and subglottis but with more prolonged intubation there was full thickness mucosal necrosis, perichondritis and partial destruction of the arytenoid and cricoid cartilages. Although the severity of the injury progressed with time and many of the most severe injuries occurred early, in the second and third weeks of intubation, the larynx usually healed despite the continued presence of the endotracheal tube. Prolonged intubation on its own does not appear to be an important factor in the production of severe laryngeal injury nor, therefore, the subsequent complications such as subglottic stenosis.