Collapse occurs in OSA and HS despite continued breathing efforts, whereas central sleep apnea (CSA) describes a pause in respiration caused by a lack of respiratory effort. In CSA, unusually low levels of circulating carbon dioxide (or hypocapnea) during sleep fails to stimulate respiration, resulting in apnea. Most cases of hypocapnea are associated with a coexisting condition such as cardiac failure, stroke, or other neurologic disease. However, hypocapnea may also occur spontaneously, as the result of an overactive response to rising levels of carbon dioxide in the blood. Patients present with daytime drowsiness, and occasionally, sleep-maintenance insomnia, which is relatively rare in OSA, and may help to differentiate these two conditions.
Review Date:
7/5/2013 Reviewed By: |