Infants and children are not simply miniature adults, and their specialized anatomy and physiology significantly impact the basic approach to pediatric laryngoscopy. As with any endeavor, and particularly in management of the pediatric airway, preparation is the key to success. The heightened emphasis on adequate preparation for airway instrumentation stands in reverse proportion to the age of the patient. This focus may be attributed to a threefold increase in oxygen consumption, increased closing volumes, and consequently a predisposition to rapid oxygen desaturation. As such, multiple sizes of oropharyngeal and nasopharyngeal airways, laryngoscopy blades, and endotracheal tubes (ETTs) should always be immediately available (Fig. 41-1). Furthermore, when proceeding with induction through preexisting intravenous access, adequate preoxygenation is strongly advised to help mitigate desaturation during direct laryngoscopy.

Optimal positioning for direct laryngoscopy depends on the age of the patient and the position of the laryngoscopist (sitting vs standing). In children older than age 6, positioning is similar to adults in the classic “sniffing” position: elevation of the head 5 to 10 cm with a pillow beneath the occiput, extension of the head at the atlantooccipital joint, and alignment of the oral, pharyngeal, and tracheal axes to facilitate laryngeal visualization. Infants, however, due to their disproportionately large occiput, do not usually require elevation of the head to adequately achieve anterior displacement of the cervical spine and appropriate laryngeal visualization. Shoulder rolls for neonatal laryngoscopy are only beneficial when the practitioner is seated (the classic position of the otolaryngologist) and may actually hinder the standing practitioner (Fig. 41-2). A more beneficial position for standing neonatal intubation provides for an assistant holding the head in slight extension, the shoulders flat on the operating room table, with the patient placed at the level of the xiphoid process of the intubator.

After inhalational induction via mask and establishment of an intravenous route for medication, various pharmacologic approaches may be used to achieve appropriate conditions for direct laryngoscopy and intubation, both with and without muscle relaxation. Most infants and children without cardiovascular disease, requiring endotracheal intubation for airway protection during short surgical procedures, may be intubated without muscle relaxation, avoiding the potential adverse effects of these medications. Inhalational sevoflurane (6% to 8%) in oxygen is used with assisted and controlled ventilation until the child is motionless, apneic, and pupils are fixed, with careful attention to heart rate and blood pressure to avoid myocardial depression. Laryngoscopy can then be facilitated by propofol 1 to 2 mg/kg, and spraying of the vocal cords with 1 mg/kg of lidocaine (1% to 2%) via an atomizing device, after achieving adequate depth of anesthesia for intubation. For elective procedures during which muscle relaxation is indicated, intermediate acting nondepolarizing muscle relaxants such as rocuronium (0.3 to 0.5 mg/kg infant, 0.6 to 1.2 mg/kg children) or cisatracurium (0.1 to 0.2 mg/kg) are used to facilitate endotracheal intubation. For patients with a full stomach, requiring a rapid-sequence intubation, the dose of rocuronium may be increased to 1.2 mg/kg to achieve intubating conditions within 60 seconds in conjunction with an induction agent, such as propofol (2 to 4 mg/kg), thiopental (5 to 6 mg/kg), or ketamine (1 to 3 mg/kg). The FDA “black box” warning cautions against the use of succinylcholine for routine pediatric airway management, due to several case reports of hyperkalemic cardiac arrests in children with undiagnosed Duchenne muscular dystrophy (mortality 55%) (Fig. 41-3). As such, the use of succinylcholine in pediatric anesthesia is restricted to emergency intubations, or those situations where the airway must be immediately secured, such as laryngospasm, difficult airway, or full-stomach precautions. The routine administration of atropine (0.01 to 0.02 mg/kg) or glycopyrrolate (0.005 to 0.01 mg/kg) to prevent bradycardia and hypotension is now less common with the change from halothane to sevoflurane for standard pediatric inhalational induction.