Airway

• External
  • Large occiput
  • ↓ BMI
  • ↑ Neck flexion and extension
• Oral Cavity
  • Small oral cavity
  • Relatively large tongue
  • Potentially loose primary dentition
• Pharynx
  • Waldeyer’s ring
    • Enlarged adenoids
      • See Figure 3.17 for Brodsky score
    • Lingual, tubal, and palatine tonsils
    • Grow rapidly until age five to seven years, then physiological atrophy
• Larynx
  • Cephalad, anterior position
• Glottis
  • Vocal cord location
    • 0–12 months: at C₃
    • 1–2 years: at C₄
    • 3–10 years: at C₄–C₅
    • Adults: at mid C₅
  • Angled anterior‐inferior to superior‐posterior
    • May make insertion of endotracheal tube challenging
  • Broad, floppy, U‐shaped epiglottis in young children
• Trachea
  • Flexibility of cartilaginous structures can predispose to dynamic obstruction with changes in airway pressure
  • Calcification of tracheal structures occurs in teenage years
  • Narrow tracheal diameter
    • For ETT sizing, see page 299
    • In an emergency, diameter of patient’s little finger can be used to guide ETT sizing
    • Historically taught that the narrowest part of the pediatric airway was the circular cricoid cartilage
    • Modern imaging studies demonstrate that the narrowest part is either at the vocal cords (as in adults) or the elliptical subglottic area
    • Cuffed tubes could be used for patients >3 kg [1]

Fluid Management (Figure 7.1)