[Sonographic analysis of postextubation stridor in neonates and children with low birth weight after long-term artificial ventilation].

In a group of 23 neonates with mean birth weights of 1470 g (range 1200-3980 g) who had orotracheal intubation for an average period of 12.6 days (range 5-96 days) sonagraphic frequency analysis of 86 stridors 1-3 hours after intubation was performed. According to the results of the frequency analysis more than 97.6% of the stridors are supraglottic (84 of 86 analyzed stridors). The laryngeal and tracheal type of stridor was recorded only in two children. The finding is surprising and does not confirm the widely accepted view that neonates after extubation are threatened with oedema of the larynx or stricture at this or a distal level. As elective postextubation laryngoscopy is controversial, acoustic frequency analysis of stridor after extubation is a suitable alternate method in investigations of the clinical condition of the infant and serves the clinician as an indication on the level of stenosis of the airways.