Long-term outcomes of congenital high airway obstruction syndrome (CHAOS) at a single comprehensive fetal center

OBJECTIVES: Congenital high airway obstruction syndrome (CHAOS) is characterized by over-distended lungs leading to impaired cardiac return and fetal hydrops. Survivors have been reported following prenatal spontaneous fistulization, fetal procedures to decompress the airway, or ex-utero intrapartum treatment (EXIT). The long-term outcomes of survivors are unclear. METHODS: We performed a retrospective chart review on patients diagnosed with CHAOS in our center between 2005-2025. RESULTS: Of the 28 patients with CHAOS, three (10.7%) underwent a fetal procedure to decompress the airway. Three patients (10.7%) had evidence of spontaneous fistulization. Four patients (14.3%) terminated the pregnancy and four (14.3%) had in-utero fetal demise. Twenty patients (71.4%) were live-born; of these, 14 (70%) died shortly after delivery and two (10%) died in the neonatal period. Seven patients (35%) underwent EXIT-to-tracheostomy at our center, of which four (57.1%) are long-term survivors ranging in age from 4 to 19 years old. Three patients have undergone airway reconstruction between 1.6 and 5.6 years of age; one remains tracheostomy-dependent due to recurrent airway stenosis, one patient has undergone reconstruction and is likely to be decannulated soon, and one patient had successful reconstruction and was decannulated. The fourth patient has not yet undergone airway reconstruction. CONCLUSIONS: CHAOS remains a highly morbid diagnosis, but long-term survivorship and liberation from tracheostomy is possible.