OR Playbook
Step 24 · Airway

Pediatric Airway

Why kids are different, how to size the gear, and the pearls that keep them safe.

8 min read

The TL;DR

  • Kids desaturate fast (high O₂ consumption, low reserve) and turn bradycardic with hypoxia — move quickly.
  • Anatomy: smaller airway (narrowest at the cricoid), bigger tongue, more cephalad larynx, shorter epiglottis — small edema is a big problem.
  • Flow: premed for separation → mask induction → IV after asleep (must be past stage 2 before the IV — laryngospasm).
  • Infants: PAT — Positioning (shoulder roll), Atropine (pretreat ~10 mcg/kg), Tube (have a half-size smaller).
  • ETT by age (uncuffed) ≈ (age/4) + 4; confirm with a leak at 15–20 cmH₂O; have sux + atropine ready.

01Why kids are different

Anatomy: - Smaller airway overall (an infant's diameter ≈ their pinky); narrowest at the cricoid ring (so a tube through the cords may still not fit). - Larger tongue relative to the mouth. - Larynx is more cephalad (higher), and the epiglottis is shorter/narrower. - Because the airway is small, a little edema causes a big drop in cross-section.

Physiology: kids have high O₂ consumption (infants ~2× adults) and low reserve, so they desaturate fast, and they become bradycardic (→ asystole) quickly with hypoxia. The takeaway: once trouble starts, you have very little time — secure ventilation/oxygenation quickly.

Pearls
  • Some peds providers keep sux + atropine drawn in small syringes with an IM needle ready for airway emergencies.

02Flow & sizing

Patient flow: NPO; premedication for separation anxiety (or a parent accompanies) — midazolam 0.5 mg/kg PO; mask induction with sevoflurane; IV after the patient is asleep — and critically, past stage 2 before attempting the IV (stage-2 stimulation → laryngospasm); then LMA or ETT.

Infants — PAT: Positioning (a shoulder roll, not an adult-style head pillow, because of the large occiput); Atropine (pretreat ~10 mcg/kg to protect the heart rate if intubation runs long); Tube (have an ETT a half-size smaller ready).

ETT / blade by age (uncuffed):

AgeBladeETT
Term neonateMiller 13.0–3.5
0–8 moMiller 13.5–4.0
8 mo–2 yMiller 1 / Mac 24.0–4.5
2–12 yMiller 2 / Mac 2–3(age/4) + 4

For a cuffed tube, downsize by a half size. Confirm sizing with a leak at 15–20 cmH₂O — a leak < 10 (too small) or > 25 (too big, tracheal ischemia risk) means swap the tube.

03Pearls & laryngospasm

Mask/LMA/intubation pearls: properly sized gear is everything; keep the mask off the eyes; keep the tongue off the roof of the mouth (open the mouth slightly); a shoulder roll aids alignment; ventilate gently (kids inflate the stomach easily — an OGT can decompress). Always be ready to fall back on mask ventilation — if the SpO₂ nears 92%, stop and mask with 100% O₂. When the attending says stop, stop.

Laryngospasm (more common in kids from mask inductions and deep extubations): 1. 100% O₂, jaw thrust + firm CPAP. 2. Larson's maneuver (pressure at the laryngospasm notch behind the earlobes). 3. Propofol 0.5 mg/kg if you have IV access. 4. IM succinylcholine ~2 mg/kg if no IV.

Common mistakes
  • Things go wrong fast in peds with little reserve — be gentle (small edema compromises the airway) and use minimal force.

Concepts adapted for AnesthesiaHub from “Anesthesia Made Easy” (Jeff Steiner, DO, MBA) and standard anesthesia references, re-expressed in this site's own words. Educational use only — always verify doses against primary sources and your institution's protocols.