Stridor in the Newborn

Abstract

Stridor is an abnormal sound caused by turbulent airflow through a partially obstructed airway. It can be inspiratory, expiratory, or biphasic depending on the location of the obstruction.

The vast majority of stridor in newborns is caused by laryngomalacia, which is also the most common congenital laryngeal anomaly. In laryngomalacia, the inspiratory stridor often does not present until 2 weeks after birth and resolves by 18–24 months of age. While most cases are managed with watchful waiting, severe cases require surgery. Vocal cord paralysis is the second most common cause of neonatal stridor. Bilateral vocal cord paralysis is usually idiopathic. In certain cases, paralysis may occur secondary to central nervous system abnormalities that include Arnold-Chiari malformation, cerebral palsy, hydrocephalus, myelomeningocele, spina bifida, or hypoxia. Severe cases may necessitate endotracheal intubation and/or tracheostomy. Congenital subglottic stenosis is defined as a diameter of less than 4 mm of the cricoid area in a full-term infant and less than 3 mm in a premature infant. This condition is the third most frequent laryngeal anomaly and the most common laryngeal anomaly requiring a tracheotomy in newborns. Laryngotracheoplasty with cartilage grafting, or stenotic segment resection, and anastomosis may be required to repair the airway. Other rare etiologies of neonatal stridor include subglottic hemangiomas; laryngeal webs, clefts, and cysts; and tracheomalacia.

The clinical history is of paramount importance in orienting the surgeon to the appropriate pathology. Flexible fiber-optic endoscopy performed on the patient, while awake, often confirms the diagnosis. Management is tailored to each condition and its degree of severity.