A child’s respiratory system isn’t a scaled-down copy of an adult’s — it’s a different system with different geometry, different reserve, and different failure dynamics. That’s exactly why respiratory distress is among the most common and also the most severe reasons for calling EMS to a pediatric patient, and that’s exactly why this second installment of the PED series builds on anatomical and physiological foundations, without which discussing any further intervention makes no sense.

Anatomical differences in the upper airway

Head, occiput, and positioning

The newborn and infant have a relatively large head with a prominent occiput. In the supine position, this causes passive neck flexion, which can by itself lead to airway obstruction. Whereas in an adult the “sniffing position” with head elevation is used to achieve a patent airway, in an infant it’s often necessary to instead elevate the shoulders to compensate for the flexion caused by the large occiput and achieve a neutral head position.

Tongue and oral cavity

A child’s tongue is proportionally larger relative to the size of the oral cavity than in an adult. This narrows the space for laryngoscopy and increases the risk of obstruction by soft tissues — particularly in an unconscious patient, where loss of muscle tone pushes the tongue further back.

Position of the larynx

A child’s larynx sits higher and further forward than in an adult — roughly at the level of the C3–C4 vertebrae, whereas in an adult it’s at C4–C5. This position, together with a larger and more pliable epiglottis (often described as “omega”-shaped), makes direct visualization of the vocal cords during laryngoscopy more difficult and is one reason why pediatric laryngoscopy requires specific practice.

Shape and narrowest point of the airway

Traditional teaching describes the pediatric airway as funnel-shaped, with the narrowest point at the level of the cricoid cartilage — unlike in an adult, where the narrowest point is the glottic opening. This concept underlies the long-standing practice of preferring uncuffed endotracheal tubes in young children.

Physiological differences in breathing

High chest wall compliance means a child more readily shows visible retractions — jugular, intercostal, subcostal — with increased work of breathing, which is a valuable but also treacherous indicator: with exhaustion of the respiratory muscles, retractions can paradoxically diminish, which is NOT a sign of improvement, but of impending failure.

Newborns and young infants up to roughly 2–4 months of age are considered predominantly obligate nasal breathers. Obstruction of the nasal passages (mucus, edema) in this group can cause disproportionately severe respiratory distress compared to the same finding in an older child or adult.

Practical implications for the paramedic

Connection to the next part of the series

In PED-03, we’ll move from the airway to the cardiovascular system and thermoregulation — two further areas where age has a fundamental effect on how quickly and in what way a child decompensates.