Need Advice on Auto CPAP Settings

[fwg1947]

In October I switched from Dreamstation CPAP Pro with fixed pressure 9.0 cmH20 and Ramp and Flex turned off to DreamStation Auto CPAP with min. pressure of 5.0 and max. pressure of 15.0 with Ramp set at 4.0 and A-Flex set at 3.  As a result, my AHI immediately went from 0.9 for the last month on CPAP to over 5.0 on the Auto CPAP.  I turned Ramp and Flex off on the auto machine, which reduced the AHI some, but it is still well above what it was on the fixed pressure machine. AHI is now averaging about 5.1 but some nights have been as high as 7 or 8.  I had used CPAP fixed pressure of 9.0 for eight years on my previous machine and found it to be comfortable.  However, with the minimum pressure set at 5.0 on the auto machine, I sometimes feel like I am not getting enough air.  Also, it seems like the machine is not responding adequately to the hypopneas.
 
Here are thumbnails linked to SleepyHead charts on Imgur for the last 2 nights.  Please give me any suggestions you have for changing the settings. 


Last night (December 22, 2017):




Night before last (December 21, 2017):

[Sleeprider]

Most events are hypopnea and obstructive, with a few flow limits sprinkled in. You need to increase the minimum pressure until they drop to acceptable levels. The Philips Dreamstation is a fine machine, but it's slow to increase pressure and prevent this nonsense. Just increase pressure in 1-cm increments until you feel happy with results. My best guess is you should be at a minimum CPAP pressure of at least 7.0. For some reason you just don't give your machine the precursor warnings it needs to increase pressure, so you remain at your minimum pressure all the time. If you look at the pressure graph vs events on December 21, it's obvious the events shut-off at 7.0 cm.

[fwg1947]

Thanks Sleeprider. for the advice. I will begin experimenting with the minimum pressure tonight by increasing from 5.0 to 6.0.

[ajack]

Try 6, but I also think that with the DS, 7 would be about right. It is slower than resmed and likes to be closer to the 90/95% number. With such low pressures, you could even have 8, which is near your fixed cpap pressure.

[Milan72]

I would try the old settings of fixed pressure at 9 like your old machine and first see if you are getting the same results. Also depending on masks you use some require higher or lower pressures.

[fwg1947]

Thanks Ajack.  I'll try pressure of 6.0 for a few days and go up from there if results do not improve.

[fwg1947]

I would try the old settings of fixed pressure at 9 like your old machine and first see if you are getting the same results. Also depending on masks you use some require higher or lower pressures.

Thanks Milan72.  I have started slowly increasing the minimum pressure.  If that does not help, I'll try your suggestion of fixed pressure for comparison.  I don't think the mask is an issue because I am using exactly the same equipment (mask, nasal pillows, heated tubing, humidifier, etc.) on the new DreamStation Auto CPAP as I was using on the old DreamStation CPAP Pro fixed pressure machine.  The mask setting was x1 on both machines as specified in the DreamWear nasal pillows instructions.

[Walla Walla]

I'm guessing a minimum pressure of 8 cm clears most of it up.