Developmental Changes of Laryngeal Dimensions in Unparalyzed, Sedated Children

Abstract

In sedated, unparalyzed children, the narrowest portions of the larynx are the glottic opening (vocal cord level) and the immediate sub-vocal cord level, and there is no change in the relationships of these dimensions relative to cricoid dimensions throughout childhood.

Extubation Failure after Neonatal Cardiac Surgery: A Multicenter Analysis

“…Uncuffed endotracheal tubes have historically been more commonly employed in pediatric patients because of the notion that the narrowest point of the airway in young children is at the level of the circumferential, non-distensible cricoid cartilage below the vocal cords [20,21]. Uncuffed endotracheal tubes, when inserted into these airways, should optimally be large enough to seal the cricoid ring but small enough to allow an air leak when airway pressures of 20 to 30 cmH2O are applied [22]. As our understanding of the developmental changes of the upper airway has improved [22] and modern low-pressure cuffed endotracheal tubes have become readily available [23], uncuffed endotracheal tubes have fallen out of favor in some pediatric institutions.…”

“…Uncuffed endotracheal tubes, when inserted into these airways, should optimally be large enough to seal the cricoid ring but small enough to allow an air leak when airway pressures of 20 to 30 cmH2O are applied [22]. As our understanding of the developmental changes of the upper airway has improved [22] and modern low-pressure cuffed endotracheal tubes have become readily available [23], uncuffed endotracheal tubes have fallen out of favor in some pediatric institutions. Despite this evolution, use of uncuffed endotracheal tubes is still relatively common for neonatal populations, where concern for airway damage from excessive cuff pressures is especially fervent.…”

Laryngeal mask airway and tracheal tube cuff pressures in children: are clinical endpoints valuable for guiding inflation?

“…Cuffed tracheal tubes were avoided as they were thought more likely to produce subglottic trauma, since the cricoid is the narrowest part of the paediatric airway. However, recent studies show that the paediatric cricoid is primarily an ellipsoid structure [33]. This means that if a circular uncuffed tube is inserted into a noncircular cricoid lumen, a reasonable seal can only be attained by significant pressure on the lateroposterior walls of the cricoid.…”

Tubos endotraqueales con cuff en anestesia pediátrica: ¿aumentan el riesgo de estridor post-extubación? Estudio observacional, cohorte prospectiva

“…The cuffed tracheal tubes effect on stridor risk, (adjusting for confounders), was non-significant: OR = 2,2; Conf. Interval 95% [0, [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]; p = 0,5. Conclusions: The use of cuffed endotracheal tubes did not increase the risk of post-extubation stridor in children.…”

“…Estos beneficios han impulsado la utilización de tubos con cuff en anestesia pediátrica 7 , sin aumentar los efectos adversos, lo que ha sido demostrado en 2 estudios que aportan evidencia de primera categoría 8,9 . Recientemente con el advenimiento de nuevas técnicas diagnósticas 10,11 , se ha cuestionado el paradigma clásico, debido a que las imágenes obtenidas en niños sedados y en ventilación espontánea ubican el punto más estrecho de la laringe en la abertura glótica, sin mayores cambios durante el desarrollo posterior 10 . Pese a lo anterior, aún persiste dudas 12,13,14,15,16 respecto a la seguridad del uso de tubos con cuff.…”