About CSA | ResMed
About CSA

About Central Sleep Apnoea (CSA)

Central Sleep Apnoea (CSA) is a type of sleep-disordered breathing. Unlike Obstructive Sleep Apnoea (OSA) patients who have partially or fully blocked upper airways that restrict breathing, patients with CSA have a lack of respiratory drive. This means either the breathing centre in the brain fails to trigger breathing, or the signal to inhale is not transmitted properly to the rest of the patient’s body.

It can be challenging to treat patients with CSA, who often experience less or different symptoms than OSA patients. Adaptive servo-ventilation (ASV)* featured in AirCurveTM 10 CS PaceWaveTM is an appropriate choice for treating most of these more complex patients.

Central Sleep Apnoea (CSA)
is SDB in which the effort to breathe is diminished or absent, typically for 10 to 30 seconds either intermittently or in cycles, due to instability in the body's feedback mechanisms that control respiration, also called lack of respiratory drive.

Complex Sleep Apnoea (CompSA) is a form of CSA that manifests during CPAP therapy. CompSA is the usual term used in Sleep Medicine to refer to any CSA during CPAP therapy.

Transient CSA
is a type of CompSA, and the term indicates that CSA was, at least partially, present at the diagnosis of SDB and disappears during CPAP therapy.

Persistent CSA
is a type of CompSA, and the term indicates that CSA was, at least partially, present at the diagnosis of SDB, but does not disappear during CPAP therapy.

Emergent CSA
is one kind of CompSA. The term indicates that the CSA has appeared during CPAP therapy. The only category of CompSA recognised by The International Classification of Sleep-Disorders-Third Edition.

Obstructive Sleep Apnoea (OSA)
is sleep disordered breathing (SDB) caused by partial or complete obstruction of the upper airways.

3,5% of OSA patients suffer from CompSA.1

Up to 45% of patients on opioids for chronic pain suffer from CSA or CompSA.2

5-12% of ischemic and hemorrhagic stroke and transient ischemic attack (TIA) patients suffer from primarily central apnoeas.3



Symptoms of CSA may include excessive daytime sleepiness, poor concentration, morning headaches, depressed mood, weight gain…

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Treatment of CSA

Compared to other forms of PAP therapy, ASV offers significant benefits for the treatment of central SDB.

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SERVE-HF study

SERVE-HF has become a key study in its field, contributing significantly to ASV clinical practice.

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CSA during CPAP therapy study

Switching patients with persistent or emergent CSA from CPAP to ASV may improve compliance.

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* ASV therapy is contraindicated in patients with chronic, symptomatic heart failure (NYHA 2-4) with reduced left ventricular ejection fraction (LVEF ≤ 45%) and moderate to severe predominant central sleep apnoea.

  1. Javaheri S., Smith J., Chung E., The Prevalence and Natural History of Complex Sleep Apnea, Journal of Clinical Sleep Medicine, Vol.5, No. 3, 2009.
  2. Mogri M et al. Hypoxemia in patients on chronic opiate therapy with and without sleep apnea. Sleep Breath, 2009;13:49-57.
  3. Karin G. Johnson and Douglas C. Johnson. Frequency of Sleep Apnea in Stroke and TIA Patients: A Meta-analysis. J Clin Sleep Med, 2010;6(2):131-137.