What are the key differences in managing adult and pediatric airways?

Key Anatomical and Physiological Differences Between Pediatric and Adult Airways

Pediatric airways differ fundamentally from adult airways in anatomy, physiology, and respiratory control, requiring distinct management approaches that prioritize the child's unique vulnerability to rapid deterioration and higher oxygen consumption.

Critical Anatomical Differences

Pediatric patients have distinct maturational differences in airway structure, respiratory muscles, chest wall configuration, and respiratory reflexes that directly impact airway management strategies 1. The following anatomical features distinguish pediatric from adult airways:

Upper Airway Structure

• Children have proportionally larger tongues and more anterior larynges, making direct laryngoscopy more challenging for providers who do not routinely intubate pediatric patients 1.
• The pediatric airway is funnel-shaped with the narrowest point at the cricoid ring (in children under 8-10 years), whereas adults have a cylindrical airway with the narrowest point at the vocal cords 1.
• Infants require neutral head positioning, while older children benefit from the "sniffing position" with chin elevation; a rolled towel under the shoulders may improve airway patency in younger children 2.

Laryngeal Positioning

• The pediatric larynx sits more cephalad (C3-C4 level) compared to adults (C4-C5), and the epiglottis is proportionally longer, narrower, and more omega-shaped 1, 3.
• The shorter trachea in children increases the risk of mainstem bronchus intubation and accidental extubation with even minor head repositioning 1.

Physiological Vulnerabilities

Oxygen Consumption and Desaturation Risk

Children have significantly higher metabolic rates and oxygen consumption (6-8 mL/kg/min) compared to adults (3-4 mL/kg/min), combined with lower functional residual capacity, resulting in dramatically faster oxygen desaturation during apnea 1. The younger the child, the shorter the safe apnea time before hypoxemia develops 1.

Respiratory Mechanics

• Pediatric chest walls are more compliant with weaker intercostal muscles, making them more prone to paradoxical breathing and respiratory fatigue 1.
• Children demonstrate different respiratory reflexes and control mechanisms, with cough sensitivity influenced by airway caliber and age rather than sex (unlike adults where sex differences predominate) 1.

Management Implications

Airway Device Selection

Both cuffed and uncuffed endotracheal tubes are acceptable for pediatric intubation, but cuffed tubes may reduce reintubation rates without increasing complications when cuff pressure is monitored and kept below 20-25 cm H₂O 1. This represents a shift from historical practice that exclusively used uncuffed tubes in young children.

Muscle Relaxant Dosing

Succinylcholine dosing varies significantly by age in children: up to 1 month requires 1.8 mg/kg, 1 month to 1 year requires 2 mg/kg, 1-10 years requires 1.2 mg/kg, and over 10 years requires 1 mg/kg 1. Rocuronium at doses >0.9 mg/kg provides an alternative when succinylcholine is contraindicated 1.

Ventilation Strategies

Bag-mask ventilation requires careful attention to avoid excessive pressures that cause gastric inflation; slow ventilation with just enough tidal volume to achieve visible chest rise minimizes this risk 1. Two-person bag-mask technique is preferable when available, particularly in patients with airway obstruction or poor lung compliance 1.

Rapid Sequence Intubation Considerations

Rapid sequence intubation in children requires muscle relaxants to optimize conditions and minimize the critical period between loss of consciousness and airway protection, which must be even shorter than in adults due to rapid desaturation 1. Cricoid pressure is NOT routinely recommended as it can impede ventilation without proven aspiration prevention benefit 1, 4.

Equipment and Monitoring Requirements

Continuous monitoring with pulse oximetry and waveform capnography is mandatory for all pediatric sedation and airway management, as children can rapidly transition from light to deep sedation with loss of protective reflexes 5. Age- and size-appropriate resuscitative equipment and personnel skilled in pediatric airway management must be immediately available 5.

Videolaryngoscopy Applications

Videolaryngoscopes improve glottic visualization and first-pass success rates in children with anticipated difficult intubation or polymalformative syndromes, though success depends on device type, operator expertise, and patient characteristics 1. In children without difficult airway criteria, videolaryngoscopy shows no significant advantage over direct laryngoscopy with Macintosh blade 1.

Supraglottic Airways

Supraglottic airways provide easier placement than endotracheal tubes but do not provide definitive airway protection or mitigate aspiration risk 1. Second-generation supraglottic devices with gastric drainage ports are preferred when available 1.

Critical Pitfalls to Avoid

• Avoid rapid intravenous administration of sedatives in pediatric patients, especially those with cardiovascular instability or hemodynamic compromise 5.
• Never use codeine-containing medications for cough in children due to serious respiratory depression risk 1.
• Recognize that pediatric patients undergoing upper airway procedures (endoscopy, dental work) are particularly vulnerable to desaturation and hypoventilation from partial obstruction 5.
• Do not rely on clinical signs alone to confirm endotracheal tube placement; waveform capnography is essential as unrecognized esophageal intubation dramatically increases aspiration and mortality risk 4.