2020A07 Describe the anatomy of the neonatal airway, and what implications this has for airway management.

· Upper airway

· Lower airway

· Other

Upper airway:

Narrow upper airways:

· Narrow nasal passages

· Large tongue

· Narrow pharynx

· ↑ Resistance. Provides auto-PEEP

· Guedel airway useful during mask ventilation

Obligate nose breather because of

· Large tongue

· High laryngeal inlet (C3-4 cf. C6)

· Any nasal obstruction = dangerous

Prominent occiput:

· Tendency for flexion -> obstruction

· Folded towel under shoulders for bag-mask vent and intubation

Narrower lower airways

· Includes larynx, trachea and bronchi
Resistance 25cmH2O/L/s on day 2

· Note narrowest point cricoid ring (cf. glottis in adults)

· Any further obstruction = dangerous

· Risk of subglottic stenosis with prolonged intubation

· Epiglottis long, U shape, floppy

· Can be bypassed using straight bladed laryngoscope (Miller)

· Risk of glottic obstruction by misplaced LMA

· Laryngeal inlet is high C3-4 and anterior

· Larynx

· Different intubation mechanics

· Short trachea

· Risk of endobronchial intubation during neck flexion

· Risk of accidental extubation during neck extension

Risk of oxygen toxicity

· Bronchopulmonary dysplasia

· (Other: retinopathy of prematurity, necrotising enterocolitis)

Non-respiratory functions

· Innate immunity e.g. mucocilicary escalator present in neonate and adult

· Adaptive immunity: passive (from breast milk) vs endogenous. No endogenous IgG or IgA in neonatal alveolar lining fluid