ABSTRACT
Hypercapnic Central Sleep Apnea The loss of wakefulness stimulus to breathe is associated with decreased alveolar ventilation and increased arterial partial pressure of carbon dioxide (Pco2). However, the manifestations depend on the underlying clinical condition. Therefore, removal of the wakefulness stimulus to breathe results in profound hypoventilation in patients afflicted with conditions associated with impaired diurnal ventilation, such as neuromuscular disease or abnormal respiratory mechanics. Hypoventilation manifests as a central apnea or hypopnea; the ensuing transient arousal partially restores alveolar ventilation until sleep resumes. Thus, central apnea under these circumstances represents nocturnal ventilatory failure in patients with marginal ventilatory status or worsening of existing chronic ventilatory failure.
