Acquired subglottic cysts in the low-birth-weight infant. Characteristics, treatment, and outcome

G. J. Downing, L. K. Hayen and H. W. Kilbride
Department of Pediatrics, Children's Mercy Hospital, Kansas City, Mo. 64108-9898.

OBJECTIVE--To provide a descriptive summary of characteristics, including demographics, symptoms, risk factors, and outcome of acquired subglottic cysts identified in the neonatal period. DESIGN--Patient series. SETTING--A tertiary neonatal care unit and referral neonatal follow-up clinic. PARTICIPANTS--One hundred seventy-four preterm infants undergoing flexible bronchoscopy, 21 (12%) referred for airway evaluation because of symptoms and 153 (88%) examined consecutively following 7 days or more of endotracheal intubation. INTERVENTION--None. MEASUREMENTS/RESULTS--Subglottic cysts were identified in 11 (7.2%) of 153 preterm infants examined prospectively at discharge from the neonatal intensive care unit after prolonged intubation and two (10%) of 21 infants referred for airway evaluation. Infants with subglottic cysts were extremely preterm (mean +/- SEM gestation, 26.7 +/- 0.5 weeks) and very low birth weight (894.6 +/- 64.6 g). The mean duration of intubation was 28.5 +/- 5.0 days. Most infants, particularly those with large cysts, were symptomatic with stridor, hoarseness, or obstructive apnea. In two cases, airway symptoms began after discharge from the neonatal intensive care unit. Ten (91%) of the 11 patients were discharged receiving home oxygen. Generally, multiple cysts were present in the subglottic space, most prominently located in the posterior aspect of the trachea. Three of five patients with large cysts received a tracheostomy. Two additional patients had surgical marsupialization of the cysts, and six others experienced resolution without treatment. One patient with large cysts died of viral pneumonia 10 months after surgical intervention. An additional patient with large cysts died before surgical intervention secondary to chronic lung disease and cor pulmonale. All surviving infants had resolution of signs of airway obstruction and 10 of the 11 did not require supplemental oxygen or have symptoms of chronic pulmonary disease at age 1 year. CONCLUSION--Intubation-acquired subglottic mucous cysts in the neonate may occur more commonly than was previously recognized. Symptoms of this lesion may mimic features of chronic lung disease. Early identification of the cysts with flexible bronchoscopy is important since airway compromise may progress and surgical intervention may be lifesaving.