AHI, Pressure vs Good Sleep

[wordjoy]

So after over 10 years on a CPAP set at 14, sleeping pretty well most of the time and little medical follow up in between I just got my new Intellipap Auto.. which for the first time gives me lots of data and control over the machine.

Dr prescribed range for 10-18.

After the first night, the next two nights it is pretty much pegged down at 10. AHI is under 5. Snores detected is under a dozen.

So I tried moving the lower down to 9. Same thing number wise, pegged at 9 for the full night. But I was waking up and restless much more than usual.

Left it there last night and wook up 2 hours later.. and since I had the PC next to me, hooked up to the machine and move the lower pressure back up to 10.

In both settings it was pegged at the lowest setting most of the night. It will jump very rarely, near the time I wake up some.

The states say I am fine even at 9.. but I am pretty sure my sleep was not good at all because of the lower pressure (thinking about moving it up a bit now closer to my 10 year CPAP setting.

Anyone see this were your sleep is bad but the numbers show no problem?

[Sleeprider]

Maintaining an adequate minimum pressure is the "big secret" behind optimizing an auto machine. Good job with the experimentation and using the feedback.

[AshSF]

AHI is a good indicator but it is not the perfect indicator. A PAP machine has 2 main purposes:
1) Keep your O2 levels in normal range. Sometimes, you need a bit higher pressure to keep your O2 in normal range than what is needed to get AHI to < 5. This is one of the reasons why a lot of people report having the best sleep in years on the titration night but failing to replicate it later on APAP.
2) Promote good sleep architecture. So that you are not getting knocked out of deeper sleep stages to shallower ones. This is why you feel groggy in the morning even though your AHI is good. Here the culprit may be RERAs which can be reduced typically by a bit higher pressure. OR it is microarousals caused by pressure changes in APAP. In such case, going to straight pressure may be the answer.

Also, before you get to this, you need to make sure your data is reliable. For that you need to make sure your leak rate is less than the max limit of machine sensors. One more thing: Since its early days of PAPing for you , things take a bit of time to stabilize. You may want to make only one change every 7-10 days.

[wordjoy]

Thanks that helps.. just as a sanity check.. I know its easy to get data obsessed. I remember with my first CPAP I had this little test I was suppose to take on the machine once in a while answering questions. So must remember how I feel is data too.

SO I think I will let it sit at 10 and use the 9 experience to tell me that is low enough even if the machine isn't catching the effects of lower pressure.

BTW leaks are very low, IE no other signs of issues except sleep quality .

[wordjoy]

So just to follow up on this.
Moved my lower pressure to 11 and ramp start to 8 for 10 minutes (really don't need ramp)
Snores dropped to zero and AHI was low.. until early morning when the mask got loose I guess.. leaks up, System increased pressure moving up to 17 etc.
So what I can surmise is that what the Intellipap with its current settings uses to adjust pressure and what affects my sleep are not 100% inline.
But that I sleep well with 11 vs my previous 14 is good to know.

[MobileBasset]

I experienced exactly the same phenomenon. According to AHI and O2 saturation 8cm was good however I sleep and feel better at 10cm because of RERA type flow that was disrupting my sleep. I increased the min EPAP on my Bilevel machine to keep the pressure up where I like it.
I don't use the ramp.