Pediatric emergency medicine trisk 634

The neonatal larynx is less than one-third the size of an adult Even a small obstruction can lead to rapid deterioration of the baby’s respiratory status Always triage rapidly Respiratory distress in infants with Pierre Robin sequence, micrognathia, or low tone affecting airway patency may be relieved by placing prone or by placing a nasopharyngeal trumpet Infants with laryngomalacia often have associated gastroesophageal reflux Remember to ask about reflux symptoms and treat accordingly Laryngotracheomalacia will improve at approximately 18 months of age Pierre Robin Syndrome Pierre Robin syndrome describes a triad of micrognathia (small jaw), glossoptosis (downward displacement and retraction of the tongue), and a U-shaped cleft of the small palate It occurs in in 8,500 live births During the 8th to 10th week of embryologic development, the small jaw places the tongue posteriorly causing it to lie between the two developing shelves of the soft palate, hindering their fusion This single mechanical incident produces this sequence of events; hence, Pierre Robin syndrome is actually a sequence It may also occur as part of other syndromes (e.g., Stickler or Velocardiofacial syndrome) Symptoms of airway obstruction (stridor, respiratory distress, and cyanosis) are variable depending on the degree to which the tongue obstructs the nasopharynx posteriorly Neonates can also present with feeding difficulty and failure to gain weight because of the cleft palate and poor breathing–swallowing coordination Severe cases are diagnosed in the nursery and remain hospitalized Milder cases may present in the emergency room with worsening respiratory distress or aspiration Examination of the face is notable for micrognathia and cleft of the soft palate ( Fig 96.34 ) The baby may have audible stridor or retractions that worsen when placed supine Initial management should include placing the baby prone to relieve airway obstruction by allowing the tongue to fall away from the nasopharynx Infants that not respond may benefit from nasopharyngeal airway placement or an endotracheal tube placed nasally to break the seal between the posterior tongue and pharynx that is causing the obstruction Nasal CPAP may establish patency of the airway Intubation and escalation of respiratory support to mechanical ventilation may be required if the infant is in severe respiratory distress Infants with Pierre Robin syndrome should be continually monitored while in the ED and admitted to the intensive care unit for ongoing serial monitoring for cardiorespiratory deterioration Blood gas analysis may reveal chronic carbon dioxide retention Consultation with a craniofacial specialist is advised Otolaryngology evaluation may reveal other nasal or nasopharyngeal anomalies contributing to the obstruction A geneticist should also be consulted if other syndromic features are present Polysomnography may be helpful in determining the degree of obstruction or apnea and rule out central causes in infants who not have overt cardiorespiratory events FIGURE 96.34 Lateral view of an infant with Pierre Robin sequence Note the hypoplastic mandible resulting in retrognathia (Courtesy of Joseph Losee In: Orebaugh SL, Bigeleisen PE, eds Atlas of Airway Management 2nd ed Philadelphia, PA: Lippincott Williams & Wilkins; 2011 With permission.) Laryngotracheomalacia Laryngotracheomalacia accounts for approximately 60% to 70% of laryngeal problems in neonates and infants It develops as a result of a low laryngeal tone thought to be related to neurologic immaturity of the newborn and can be compounded by the presence of gastroesophageal reflux disease (GERD) Neonates present around to weeks of age with noisy breathing or coarse inspiratory stridor that is accentuated by agitation, crying, and being in a supine position Stridor improves at rest and in the prone position Severe cases may present with cyanosis, apnea, choking, and feeding difficulties Laryngomalacia improves over time with complete resolution by approximately 18 months of age Severe airway obstruction can occur when there are secondary lesions, such as neuromuscular disorders, subglottic stenosis, or vascular rings Laryngomalacia or tracheomalacia may simulate respiratory distress, with noisy respirations originating in the upper airway, but oxygen saturation and chest radiographs are normal Clinicians should also look for signs and symptoms of GERD, which are commonly associated with laryngomalacia The reflux of gastric content causes swelling of the vocal cords but it is also thought that laryngomalacia causes increases in negative intrathoracic pressure in an attempt to overcome the laryngeal obstruction, and this incites gastric contents to reflux In moderate to severe cases, diagnosis can be confirmed by flexible fiberoptic nasolaryngoscopy performed at the bedside by an ear, nose, and throat (ENT) surgeon ( Fig 96.35 ) ENT consultation for fiberoptic laryngoscopy is also recommended for mild cases with progressive symptoms or other associated symptoms Occasionally, the ENT surgeon will request a modified barium swallow or rigid bronchoscopy to rule out secondary comorbidities in cases where stridor is out of proportion to the degree of laryngomalacia seen on flexible laryngoscopy or in the presence of aspiration suspicious for posterior laryngeal cleft or tracheosophageal fistula Management is mainly conservative (watchful waiting) as infants will outgrow the condition Control of reflux with positioning after feeds and acid suppression therapy may be helpful Surgery (supraglottoplasty) is rarely required and is only indicated for cases with severe obstruction, hypoxic episodes, pulmonary hypertension, and failure to thrive FIGURE 96.35 Laryngomalacia affecting the posterior airway with collapse of the aryepiglottic folds and arytenoid tissue during inspiration (Reprinted with permission from McMillan JA, Feigin RD, DeAngelis CJ, et al Oski’s Solution Philadelphia, PA: Lippincott Williams & Wilkins; 2006.) Vocal Cord Paralysis Vocal cord paralysis accounts for 10% to 20% of laryngeal problems in neonates and infants Unilateral vocal cord paralysis is more common than bilateral Most cases are idiopathic in nature, however, neurologic disorders (Arnold–Chiari malformation, hydrocephalus, brainstem anomalies, encephalocele, leukodystrophy, myasthenia gravis, spinal muscle atrophy, and other neuromuscular disorders), cardiac disorders (tetralogy of Fallot, VSD, closure of a patent DA, and vascular rings), genetic (autosomal dominant bilateral palsy), and birth trauma have also been implicated in the etiology In most unilateral cases, neonates will present with a weak cry; additional symptoms related to aspiration and feeding difficulties may be present Neonates with bilateral vocal cord palsy present with a good cry but biphasic stridor Vocal cord paralysis causing respiratory distress may require intubation in severe cases The first