4 Weeks of CPAP, no compliance issues, but more tired than before

[nirmal]

Hello all,

I am using CPAP (Auto/Pmin:9,Pmax:13) since 4 weeks after I was diagnosed with severe OSA (AHI 86). I had absolutely no symptoms of Sleep Apnea like tiredness etc. I am 41 and otherwise healthy and I guess my body somehow made up for it. I adapted to CPAP pretty well and had no issues with pressure, mask, mask-leak etc. I am falling asleep within 5-10 minutes and sleep throughout the night. The AHI came down from 86 to 5 (2 oAHI, 1 cAI, 3 cAHI) but I am damn tired after the first 2-3 days of CPAP. I am tired during the day and only want to sleep more (all the symptoms I should have had with an untreated AHI of 86).

I talked to my provider after the first week and they were saying that it could be because I am getting used to it. Now after 4 weeks I am still dead tired. I can understand my sleep data pretty well by now (I guess). I do not see anything wrong there in there. Also my SP02 is between 94 and 97 through out the night (see below). I tried few hours without CPAP (to test) and I could see the SP02 falling below 90. I am struggling to find reasons for why I am tried now and not before. 

I am only reading and reading about Sleep Apnea these days and I can think of only two reasons.

1. I have developed Complex Sleep Apnea (CompSAS). I did not have Central Apnea before. Even if it is CompSAS, the cAHI of 3 still is under 5 which should not cause problems. Also as my SP02 is not falling I do not think it is causing arousals affecting my sleep efficiency.
2. I am not falling into deep sleep. My SP02 is more or less a straight line, perhaps too perfect during sleep, indicating that I am not falling into deep sleep. The CPAP and its pressure is not letting me go into deep sleep. I tried reducing the pressure (from 9 to 6) but I could not then breathe anymore under the low pressure and had to increase it again. I also noticed that I cannot breathe with the pressure of 5 during ramp-up which I could earlier and had to turn off ramp-up feature now.

Can anyone please explain me what's going wrong? I am damned tired even with 100% CPAP compliance and theoretically good sleep data (minus sleep-efficiency)?

Thanks in advance for your help.

   
The AHI on this particular day was 6, but the it has fallen below 6 now.

   

[eseedhouse]

I'd be wary of drawing conclusions from your first few weeks of therapy - you are dealing with a small sample after all.

That said there are a number of things that can cause this. In my own case after a month of therapy I still felt I was going "down hill". Fortunately the protocol my DME provider followed gave me an overnight oxymetry after a month and that found that, though my AHI was well controlled, my oxygen levels were still too low during the night. My respirologist then prescribed supplemental oxygen at night and that turned things around.

I am not you, so please don't jump to conclusions but talk to your equipment provider or your doctor about it. It never hurts to ask questions.

[mesenteria]

It would help to know your tidal volume.  Even so, I don't understand why you feel that a generally flat SPO2 indicates you are not falling into REM.

[nirmal]

It would help to know your tidal volume.  Even so, I don't understand why you feel that a generally flat SPO2 indicates you are not falling into REM.

You mean the tidal volume using a tidal volume calculator right? 

It says the following:
402mL if target is 6mL/Kg
536mL if target is 8mL/Kg

Regarding SP02, it was just a stupid assumption 

[PoolQ]

I can only offer some observations and perhaps a question. I will leave everything else to others way more qualified than I.
I agree with your #2. you have treated the apnea, but are not comfortable enough to go into deep sleep


From you charts I assume that BPM is breaths per minute, I am on low level O2 and to calculate usage overnight they use a standard of 20BPM, which about matches mine. Yours seems high, but I don't really know and I can't offer you any insight about it. It just seems high.

Others will post more. Hang in there