Alveolar hypoventilation and cor pulmonale associated with chronic airway obstruction in infants with Down syndrome.

Four infants with Down syndrome developed cor pulmonale and heart failure in association with chronic upper airway obstruction. Features of the sleep apnea syndrome were conspicuous; namely, noisy breathing with retraction, cyanosis and frequent apnea during sleep, and daytime lethargy and somnolence. The clinical picture masqueraded as cyanotic congenital heart disease. Arterial blood gas analyses revealed alveolar hypoventilation, especially during sleep. The nature of the obstructive element was variable. Adenoidectomy provided partial relief in one patient, and tonsillectomy and adenoidectomy resulted in temporary improvement in two others. Three patients were markedly benefitted by tracheostomy. Functional inspiratory pharyngeal closure was demonstrated fluorographically in one patient. Infants with Down syndrome may be predisposed to upper airway obstruction by virtue of hypoplasia of facial and oropharyngeal structures and generalized hypotonia. Additional obstructive elements may be contributed by hypertrophied lymphoid tissue, excessive secretions, and glossoptosis. Removal of the obstructive element is helpful, but functional obstruction may only be relieved by tracheostomy.