Complex sleep apnea
Complex sleep apnea (or mixed sleep apnea) is a form of sleep apnea in which central apneas persist or emerge during attempts to treat obstructive events with a continuous positive airway pressure (CPAP) or bilevel (BPAP) device.
Complex sleep apnea is characteristics
- The persistence or emergence of central apneas or hypopneas upon exposure to CPAP or bilevel when obstructive events have disappeared
- Complex sleep apnea patients have predominately obstructive or mixed apneas during the diagnostic sleep study, occurring at least 5 times per hour
- With use of a CPAP or bilevel, they show a pattern of central apneas and hypopneas that meets the Centers for Medicare Services (CMS) definition of CSA
A diagnosis of central sleep apnea (CSA) requirements
- An Apnea index (AI) > 5
- Central apneas/hypopneas > 50% of total apneas/hypopneas
- Central apneas or hypopneas occurring at least 5 times per hour
- Symptoms of either excessive sleepiness or disrupted sleep
The difference between central, mixed and complex sleep apnea
CSA is a form of Sleep disordered breathing (SDB) caused by the temporary absence of a signal from the brain’s respiratory center. Without this signal, there is no effort to breathe. Mixed sleep apnea is fairly common and consists of both central and obstructive components. On the other hand, complex sleep apnea consists of all or predominantly obstructive apneas which convert to all or predominantly central apneas when treated with a CPAP or bilevel devices.
Treatment of complex sleep apnea
Currently the only FDA approved treatment for CSA is ASV. However ASV treatment does not always result in improved subjective outcomes even if the AHI is brought within acceptable limits. In these cases CPAP in combination with therapies that target chemoreflex sensitivity, including use of EERS and acetazolamide, can be helpful.