Histopathologic changes in laryngeal mucosa of extremely low-birth weight infants after endotracheal intubation

Objectives: Advances in medicine have improved the survival of infants with increasingly lower birth weights. The histopathologic changes of intubation-related laryngeal injury in extremely low-birth weight infants (less than 1,000 g) have not been well known. We examined histopathologic changes in infant larynges, including extremely low-birth weight infants, after endotracheal intubation. Methods: Forty-four infants, including 21 extremely low-birth weight infants, who had been intubated for periods ranging from 10 minutes to 138 days, were examined in a whole organ serial section study. Results: As the duration of intubation increased, the ulceration was found to be larger and deeper. The injury at the subglottis and posterior glottis was greater than that at other portions. The perichondrium of the cartilage was exposed in many cases intubated longer than 8 days. Repaired epithelium that was composed of squamous epithelium was present in 6 of 7 larynges that had been intubated more than 20 days, indicating that not only injury but also the healing process occurred during long intubation. There were no obvious relationships between the degree of intubation injury and the birth weight of the infants. Conclusions: Prolonged intubation is better tolerated by infants than adults. The intubation-related laryngeal injuries of extremely low-birth weight infants were histopathologically the same as those of infants of other birth weights.