RESUMEN
INTRODUCTION: Unilateral congenital high airway obstruction syndrome (CHAOS) is caused by a complete obstruction of a mainstem bronchus with resulting hyperinflation and accelerated growth of one lung, severe mediastinal shift and hydrops. Spontaneous perforation of the atresia has been observed in CHAOS which allows hydrops to resolve but hyperinflation, mediastinal shift and a critical airway obstruction persists as the perforation is usually pinhole-sized. CASE PRESENTATION: We present a case of unilateral CHAOS presenting at 26 2/7 weeks' with observed-to-expected total lung volume (O/E TLV) of 203% with spontaneous perforation occurring at 28 weeks' with resolution of hydrops but persistence of hyperinflation and mediastinal shift with an O/E TLV of 60.5% on 34 5/7 weeks' magnetic resonance imaging (MRI), successfully managed in a 35 5/7 weeks', 1670 gm, growth restricted baby, by veno-arterial extracorporeal membrane oxygenation (VA ECMO) and resection of the tracheobronchial atresia and tracheobronchoplasty on day of life 5. The baby was separated from ECMO on post-op day 12, required tracheostomy for positive end expiratory pressure (PEEP) for tracheomalacia at 4 months. CONCLUSION: At two years of age, she has met all developmental milestones, has been weaned to room air tracheostomy collar, and is anticipating tracheal decannulation. There is persistent bronchiectasis in the hyperinflated right lung but no malacia. This is the first reported survivor of mainstem bronchial atresia suggesting the importance of preservation of the hyperplastic lung and airway reconstruction to normal long-term outcome.