CASE PRESENTATION: 9 month old female born at 39 weeks gestation via a vaginal delivery to a 23 year old mother who is otherwise healthy. The mother has another two year old daughter with known CCHS; both siblings have the same biological father who also has CCHS. The patient’s initial physical exam was unremarkable. Her Apgars were 9,9 however at one hour of life, she developed apnea and hypoxemia which warranted intubation in the NICU. Her initial arterial blood gas showed a pH of 7.15, pCO2 of 91, PO2 of 92 with a base excess of -1.5. Her initial chest X-ray was normal. Serial blood gases revealed a pattern of hypercarbia while asleep and during feeds, and improved when awake. Her white blood count, electrolytes and urine toxicology were unremarkable. 24 hours post birth, she developed bilious emesis and abdominal distention that prompted an abdominal series. It revealed megacolon that was suspicious for Hirschsprung’s disease and was subsequently confirmed with a suction rectal biopsy. The patient received a surgical resection for the latter and ultimately a tracheostomy on day 39 of life. The patient was transferred to the PICU on day 60 of life for continual medical care. She became dependent on 24 hours of ventilatory support. She would often have episodes of desaturations and reflex bradycardia that would resolve with bag-mask ventilation at bedside.