859 Trial of average volume-assured pressure support (AVAPS) to treat hypoventilation in a child with rapid-onset obesity with hypothalamic dysfunction, hypoventilation, and autonomic dysregulation (ROHHAD) and systolic heart failure

Introduction ROHHAD syndrome is a rare disorder of respiratory control and autonomic nervous system regulation with endocrine abnormalities. Although children may present with obstructive sleep apnea, their blunted respond to hypoxemia and hypercapnia is a life-threating feature, often leading to cardiorespiratory arrest. There is limited literature regarding non-invasive positive pressure ventilation (NIPPV) in these children. We report a trial of AVAPS in a child with ROHHAD syndrome. Report of case(s) Our patient is a 6-year-old male with history of rapid weight-gain (49.9 kg in 2.5 years), type-2 diabetes, and mild OSA who presented to an outside hospital (OSH) in March 2020 with acute hypercapnic hypoxemic respiratory failure. He required bilevel PAP therapy, steroids, and bromocriptine for thermoregulatory dysfunction. His clinical presentation, along with negative PHOX2B gene mutation and absence of parenchymal lung disease on chest computerized tomography suggested a diagnosis of ROHHAD syndrome. Outpatient, he was successfully transitioned to empiric AVAPS therapy. In November 2020, he presented again to an OSH in hypercapnic hypoxemic respiratory failure with new systolic heart failure with ejection fraction of 28%. After clinical stabilization, he was transferred to our hospital on CPAP 10 cmH20 with 100% FiO2 for further management. Awake blood gas was consistent with chronic hypercapnic respiratory failure; therefore, the patient was placed initially on bilevel PAP therapy empirically until an inpatient bilevel PAP titration polysomnogram was conducted. The patient remained hypercapnic and was converted to continuous AVAPS therapy starting at a tidal volume of 8.6mL/kg based on ideal body weight. AVAPS was titrated until achieving adequate ventilation, but the patient was unable to tolerate continuous NIPPV. Because of his heart failure in the setting of expected worsening respiratory failure, the decision was made to pursue tracheostomy placement for invasive positive pressure ventilation. Conclusion ROHHAD syndrome is a rare disorder that begins within the first decade of life, making adherence to daytime NIPPV difficult. This case illustrates a trial of AVAPS in a child with ROHHAD syndrome prior to tracheostomy placement. It highlights the need for future research in advanced ventilatory support strategies in children. Support (if any):