A fixed-pressure machine delivers a set pressure level all the time. This pressure setting would be provided by your Sleep Specialist, depending on the severity of your Sleep Apnea.
Preferred by many, this device varies the pressure given to allow for more comfortable therapy.
To be used for the more complex conditions, including Central Sleep Apnoea and Cheyne-Stokes Respiration (CSR). This is when breathing becomes irregular and there are both deep and shallow breaths being made.