Resmed S9 Autoset pulsing and disturbing my sleep

[zonk]

As far as I know (please correct me if I'm wrong) the Resmed machines don't actively start treating apneas or hypopneas and don't start doing the FOT thing during the ramp period.

From S9 manual: Ramp
Designed to make the beginning of treatment more comfortable, ramp is available in CPAP, AutoSet or APAP modes.
In CPAP mode during ramp time, the pressure increases from a low pressure to the prescribed treatment pressure.
In AutoSet and APAP modes, ramp time defines the period during which the pressure gradually increases from a lower more comfortable start pressure to the minimum treatment pressure before the auto-adjusting algorithm commences. In previous products in the AutoSet range, settling was the period where the device was at a minimum treatment pressure until the auto-adjusting algorithm commenced

PR Auto Algorithm http://sleepapnea.respironics.com/techno...tramp.aspx
Our SmartRamp brings a higher level of comfort to your patients.
The pressure needs of each patient are unique. With that in mind, the REMstar Auto was designed to provide the lowest pressure necessary to stabilize the airway. Even so, certain highly sensitive patients may still have difficulty falling asleep, even at a minimum therapy level. Our solution is the proprietary SmartRamp feature. With the press of a button, patients can now manage the linear increase from the minimum ramp pressure to the minimum therapy pressure. Giving your patients the ability to customize their own ramp time significantly enhances their comfort. Of course, if the patient falls asleep during this ramp time and events do occur, the algorithm will treat the events and continue to ramp up at the same rate, establishing the therapeutic minimum auto pressure faster

[geneb000]

It sounds like you are feeling the so-called FOT oscillations that the S9 uses to distinguish between OAs and CAs.

I have been using S9 Autoset for more than 3 years and have not noticed or bothered by FOT, maybe I,m not so sensitive

If the pulses are coming on all the time, it sounds like your pressure is set too low. Frequency of this on my S9 Autoset is extremely dependent on inhalation set pressure. Go up in SMALL increments until you notice a decrease. BTW, the high-pressure pulse train is how the S9 adusts pressure upward if it thinks it is needed, it does NOT just ramp up the steady-state inhalation pressure. Another possible fix would be to lower the max. pressure slightly. This would make the pulses, which take the inhalation pressure from SET to MAX and back, less noticeable, but I think you would be happier with a somewhat higher set pressure. (You could also just take the machine out of autoset mode and leave it in CPAP, but that defeats the purpose of having a pricey autoset machine). Be well!

[zonk]

(You could also just take the machine out of autoset mode and leave it in CPAP, but that defeats the purpose of having a pricey autoset machine). Be well!

Hi geneb000, welcome aboard
You,re not an Aussie by chance, machines in Australia are very pricey especially Auto-PAP, not so in US