CONGENITAL CENTRAL HYPOVENTILATION SYNDROME (CCHS) OBSTRUCTIVE SLEEP APNEA

IDIOPATHIC HYPOVENTILATION CONGENITAL CENTRAL HYPOVENTILATION SYNDROME (CCHS)

Central Sleep Apnea is characterized by interruption in breathing effort that can occur as an isolated event or in a periodic pattern. Central apnea is a manifestation of instability in the regular pattern of the respiratory control system. Laryngeal stimulation and lung inflation reflexes induce non-recurring central apneas. Arousals causing deep breaths often produce brief central apneas that may be related to transient hypocapnia. Sustained patterns of central apneas and hypoponeas are typically seen in NREM rather than REM sleep and may be amplified by arousals. Hypoxemia and pulmonary edema create sustained hyperventilation and hypocapnia that results in a very regular periodic pattern of apneas or hypopneas, often associated with some degree of sleep fragmentation. In the setting of heart failure and stroke, this pattern has traditionally been called Cheyne–Stokes respiration (CSR). CHF patients who had CSR had significantly worse survival and heart transplant–free rates when compared with appropriately matched CHF patients who did not have CSR.