Head |
Relatively large in relation to neck and chest.
Greater prominence of the occipital region.
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It favors flexion of the neck over the chest when in the supine position, making it challenging to align the airway axes and visualize structures. Facilitates upper airway obstruction. |
Nose |
Presents relatively more mucosa and lym-phoid tissue.
Smaller nostril diameters.
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Increased risk of edema, obstruction, and bleeding during nasal intubation. |
Nasopharynx |
Adenoid is hypertrophied in early childhood, and it is located in the roof and posterior wall of the nasopharynx. |
Greater risk of obstruction to nasal air flow. Risk of bleeding, edema, and tissue detachment during nasal intubation. |
Anterior mandibular space (space to which the tongue is displaced during laryngoscopy) |
Until approximately 2 years of age, the mandible is relatively hypoplastic, with consequent reduction in the anterior mandibular space. |
Airway obstruction occurs and direct visualization of glottic structures is challenging due to the disproportion between tongue size and oral cavity size.
Any other condition making the anterior mandibular space even smaller will make laryngoscopy and intubation difficult.
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Genioglossus muscle |
It is smaller and its insertion is more posterior. |
Passive airway obstruction, particularly in the supine position. |
Larynx - ligaments |
Ligaments and membranes connecting the cartilaginous structures are immature. |
Greater risk of separation of structures in trauma.
Greater susceptibility to dynamic airway collapse in the presence of respiratory obstruction.
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Larynx - location |
More cephalad position (C3-C4), making the distances between tongue, hyoid bone, epiglottis, and rim of the mouth shorter. |
Upper airway obstruction when tongue is pushed into the oral cavity. |
Larynx - angle between the base of the tongue and the glottic cleft |
The angle between the base of the tongue and the glottal cleft is more acute. |
Makes direct visualization of structures problematic. |
Larynx - mucosa and submucosa |
Tissues are abundantly vascularized, and have abundant lymphatic tissue, conferring an appearance of engorgement to the region. |
Edema and bleeding of the laryngeal fossa, epiglottis, and glottis during airway handling.
Difficult visualization of the vocal cords when using straight blades.
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Epiglottis - anatomy and location |
In newborns, the epiglottis is narrow, longer, less tonic, omega shaped (Ω), and is located more angled to the axis of the trachea. |
Elevating the epiglottis during laryngoscopy is problematic. |
Vocal cords |
They are more cartilaginous, inserted more anteriorly and have a more inferior closure. |
Edema formation during tracheal cannula insertion or using a tracheal cannula of inadequate size can make it difficult to maintain adequate ventilation after tracheal extuba-tion. More susceptible to trauma. |
Trachea |
Variable diameter (around 3 to 6 mm). |
Greater risk of airway obstruction when edema is present, which can occur when an inadequate size tracheal cannula is chosen, facilitating extubation failure. |
Cricoid cartilage |
The cricoid cartilage forms a complete ring in the airway. The cricoid cartilage, that rests on a basement membrane, is almost devoid of elastic fiber, thus it is not an expandable or mobile structure.
Until the age of 10 to 12, it is considered the greatest narrowing point of the larynx.
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Prolonged tracheal intubation or using a can-nula with an inadequate diameter increases the risk of cricoid compression injury, the likelihood of edema formation, reduction in tracheal lumen to a critical diameter and extubation failure. The injury may later progress to subglottic stenosis. |