Overview
Definition:
Laryngomalacia is the most common congenital laryngeal anomaly characterized by a collapse of supraglottic tissues into the airway during inspiration, leading to stridor.
Epidemiology:
It affects approximately 1 in 10,000 live births, with peak incidence in the neonatal period and early infancy
It is more common in males and is often associated with prematurity and other congenital anomalies.
Clinical Significance:
While often benign and self-limiting, severe cases can lead to significant respiratory distress, feeding problems, failure to thrive, and sleep-disordered breathing, requiring prompt diagnosis and management for optimal pediatric patient outcomes.
Clinical Presentation
Symptoms:
Stridor, typically inspiratory, which worsens when the infant is supine, crying, feeding, or agitated
It may be biphasic in severe cases
Associated symptoms can include poor feeding, choking, gagging, reflux, apneic spells, and failure to thrive.
Signs:
A characteristic inspiratory stridor is the hallmark sign
Other findings may include retractions, nasal flaring, tachypnea, and poor weight gain
Indirect laryngoscopy or fiberoptic laryngoscopy reveals the characteristic collapse of laryngeal structures (e.g., epiglottis, arytenoid cartilage, aryepiglottic folds).
Diagnostic Criteria:
Diagnosis is primarily clinical, based on characteristic symptoms and physical examination findings
Definitive diagnosis is confirmed by visualization of the laryngeal abnormality via flexible fiberoptic laryngoscopy, showing supraglottic collapse during inspiration
There are no specific laboratory diagnostic criteria.
Diagnostic Approach
History Taking:
Detailed history of the onset, character, and timing of stridor
Assess for triggers (position, feeding, crying)
Inquire about feeding patterns, choking, gagging, reflux, vomiting, apneic spells, cyanosis, and failure to thrive
Family history of similar conditions and perinatal history are also important.
Physical Examination:
Observe the infant's respiratory effort and listen for stridor at rest and during different maneuvers (e.g., crying, feeding)
Examine for signs of increased work of breathing (retractions, nasal flaring)
Assess feeding mechanics and weight gain
A thorough examination of other congenital anomalies is crucial.
Investigations:
Flexible fiberoptic laryngoscopy is the gold standard to visualize the laryngeal anatomy and dynamic collapse
Chest X-ray may be useful to rule out other causes of stridor or pneumonia
If reflux is suspected, pH monitoring or impedance studies can be considered
Sleep study may be indicated for severe cases with apneic spells or suspected sleep-disordered breathing
Echocardiography to rule out cardiovascular anomalies that can compress the airway is occasionally performed.
Differential Diagnosis:
Other causes of neonatal stridor include vocal cord paralysis, subglottic stenosis, hemangioma, vascular rings, tracheomalacia, esophageal atresia, choanal atresia, and central hypoventilation
Differentiating these based on inspiratory vs
biphasic stridor, positionality, and associated symptoms is key.
Management
Initial Management:
For mild, asymptomatic cases, conservative management with observation and parental reassurance is sufficient
Positioning (e.g., prone or side-lying) may help reduce symptoms
Close monitoring of feeding and weight gain is essential.
Medical Management:
Management of associated symptoms is crucial
This includes aggressive treatment of gastroesophageal reflux with proton pump inhibitors (PPIs) and prokinetics if present
Antibiotics are used for concurrent respiratory infections
Nutritional support is vital for infants with poor feeding.
Surgical Management:
Surgical intervention is reserved for severe cases unresponsive to conservative management, or those with significant respiratory compromise, feeding difficulties, failure to thrive, or apneic spells
Procedures include supraglottoplasty (widening the glottis by excising redundant aryepiglottic folds) and tracheostomy in extreme, life-threatening situations.
Supportive Care:
Nutritional support is critical for infants with feeding difficulties and failure to thrive
This may involve thickened feeds, nasogastric or orogastric tube feeding, or even gastrostomy tube feeding in severe cases
Careful monitoring of airway patency and oxygen saturation, especially during sleep and feeding, is necessary.
Complications
Early Complications:
Respiratory distress, cyanosis, apneic spells, aspiration pneumonia due to poor feeding coordination, failure to thrive, and dehydration.
Late Complications:
Persistent feeding difficulties, developmental delays, chronic gastroesophageal reflux, sleep-disordered breathing, and otitis media
Vocal cord dysfunction may persist in some cases.
Prevention Strategies:
Early identification and management of reflux, judicious surgical intervention for severe cases, and ensuring adequate nutritional support can help prevent complications.
Prognosis
Factors Affecting Prognosis:
Severity of stridor, presence of associated anomalies, degree of respiratory distress, and effectiveness of feeding support and management of reflux are key prognostic factors.
Outcomes:
Most cases of laryngomalacia are mild and resolve spontaneously by 6-12 months of age as the infant gains better muscular control and airway cartilage matures
Severe cases requiring surgery generally have good outcomes, but may require prolonged recovery and support.
Follow Up:
Follow-up is guided by the severity of symptoms
Infants with mild disease require reassurance and monitoring of growth
Those with moderate to severe symptoms, or who have undergone surgery, require ongoing assessment for airway patency, feeding issues, reflux, and growth.
Key Points
Exam Focus:
Laryngomalacia is the most common cause of congenital stridor
Diagnosis is clinical and confirmed by laryngoscopy
Management is primarily conservative, with surgery reserved for severe, symptomatic cases
Reflux is a common comorbidity.
Clinical Pearls:
Always assess feeding and growth in infants with stridor
Prone positioning can sometimes alleviate symptoms
Stridor that is biphasic or associated with significant distress warrants urgent evaluation
Don't forget to consider associated anomalies in infants with laryngomalacia.
Common Mistakes:
Over-reliance on imaging to diagnose laryngomalacia without direct visualization
Delaying definitive management in infants with significant respiratory compromise or failure to thrive
Neglecting to manage associated gastroesophageal reflux.