[Treatment] ASV settings for treatment of complex sleep apnea

[Geer1]

My gut feel with the periods of decreased respiration rate and increased expiration time are that they are a different stage of sleep that normally has a lower minute vent. The breathing seems fairly continuous and not troubled, the reason for higher pressures is because the respiration rate is slower. What I believe is happening is that the minute vent is trying to naturally drop so the machine increases its pressure, then the brain says no I don't need this much air and it slows down the breathing to try and compensate. The respiration rate falls and eventually so does the minute vent as the machine will allow it (since target minute vent is 90% of some previous set time) and then pressure slowly decreases.

I haven't watched enough ASV patients charts but I imagine if my theory is correct that this is a regular occurrence. If it isn't a semi normal occurrence it might be worth looking into. Maybe search up some other members ASV charts and see if they do the same thing.

I am curious what an ~5 min view of January 31 around 15:30 looks like (try to get a bit of the good breathing before and then a chunk of the disruption), show mask pressure graph instead of pressure for that view. Those seem to be your trouble areas and I wonder if they are central apneas the machine is working to stop or what they are.

Have you ever tried recording yourself sleep? I learned a lot doing that.

[RayBee]

My sage advice for the day: set this by feel and not so much by the numbers. I myself don't see a number on these charts that demands adjustment. Feel for various aspects should be your guide to hone in after those initial dial-in adjustments. If possible, change 1 setting and review if better or worse. A better means keep and worse means revert to what was previous.

I'm not suggesting not checking OSCAR charts. I went by feel only and when it felt off I looked at charts to see why.

I'm with Dave.

I got to the point where it seems like nothing I did would get me to the all-elusive Zero AHI number.  Then I finally realized that that was not the goal.  Feel as good-as-you-can and comfort is the goal.  For me, a pressure over 17 cmH2O would always result in aerophagia with miserable results.  So I had to play with my max EPAP and PS settings to limit my max IPAP at 17.  I played around with settings within my personal comfort limitations and have struck a balance.  But targeted as Dave said, by feel, not numbers.  I feel great no matter what the AHI numbers are.  I occasionally get a cluster of events in the first 10 minutes when I go to sleep (I see sleep when my Resp rate settles down), maybe a few more events if I reposition myself during the night, and sometimes more when I wake up.  So the numbers for me are not necessarily a good representation of efficacy.  But I know what is SWJ and account for it accordingly.  When I deduct the SWJ from the equation, my AHI averages 2.0+/-.  Not bad when I came from 40.0.

Another note...  I found that the headgear can slowly stretch out over time which causes more leaks.  Seems to be a fine line to balance proper headgear tightness in regards to mask comfort, nagging headache (too tight) , and cushion leakage (too loose).

And also, like Dave, I look more closely at the numbers and charts when something starts to go south.

All the best!  

[JoeyWallaby]

My sage advice for the day: set this by feel and not so much by the numbers. I myself don't see a number on these charts that demands adjustment. Feel for various aspects should be your guide to hone in after those initial dial-in adjustments. If possible, change 1 setting and review if better or worse. A better means keep and worse means revert to what was previous.

I'm not suggesting not checking OSCAR charts. I went by feel only and when it felt off I looked at charts to see why.

I changed it back to Min EPAP 4, Min PS 3.

My gut feel with the periods of decreased respiration rate and increased expiration time are that they are a different stage of sleep that normally has a lower minute vent. The breathing seems fairly continuous and not troubled, the reason for higher pressures is because the respiration rate is slower. What I believe is happening is that the minute vent is trying to naturally drop so the machine increases its pressure, then the brain says no I don't need this much air and it slows down the breathing to try and compensate. The respiration rate falls and eventually so does the minute vent as the machine will allow it (since target minute vent is 90% of some previous set time) and then pressure slowly decreases.

I haven't watched enough ASV patients charts but I imagine if my theory is correct that this is a regular occurrence. If it isn't a semi normal occurrence it might be worth looking into. Maybe search up some other members ASV charts and see if they do the same thing.

I am curious what an ~5 min view of January 31 around 15:30 looks like (try to get a bit of the good breathing before and then a chunk of the disruption), show mask pressure graph instead of pressure for that view. Those seem to be your trouble areas and I wonder if they are central apneas the machine is working to stop or what they are.

Have you ever tried recording yourself sleep? I learned a lot doing that.

Yes I have recorded myself before but not recently. I don't know about that theory, high PS was maintained by the machine on Jan 29 from 16:25 to 17:55, so a full sleep cycle.

My sage advice for the day: set this by feel and not so much by the numbers. I myself don't see a number on these charts that demands adjustment. Feel for various aspects should be your guide to hone in after those initial dial-in adjustments. If possible, change 1 setting and review if better or worse. A better means keep and worse means revert to what was previous.

I'm not suggesting not checking OSCAR charts. I went by feel only and when it felt off I looked at charts to see why.

I'm with Dave.

I got to the point where it seems like nothing I did would get me to the all-elusive Zero AHI number.  Then I finally realized that that was not the goal.  Feel as good-as-you-can and comfort is the goal.  For me, a pressure over 17 cmH2O would always result in aerophagia with miserable results.  So I had to play with my max EPAP and PS settings to limit my max IPAP at 17.  I played around with settings within my personal comfort limitations and have struck a balance.  But targeted as Dave said, by feel, not numbers.  I feel great no matter what the AHI numbers are.  I occasionally get a cluster of events in the first 10 minutes when I go to sleep (I see sleep when my Resp rate settles down), maybe a few more events if I reposition myself during the night, and sometimes more when I wake up.  So the numbers for me are not necessarily a good representation of efficacy.  But I know what is SWJ and account for it accordingly.  When I deduct the SWJ from the equation, my AHI averages 2.0+/-.  Not bad when I came from 40.0.

Another note...  I found that the headgear can slowly stretch out over time which causes more leaks.  Seems to be a fine line to balance proper headgear tightness in regards to mask comfort, nagging headache (too tight) , and cushion leakage (too loose).

And also, like Dave, I look more closely at the numbers and charts when something starts to go south.

All the best!  

This headgear is relatively new so shouldn't be a problem. I adjusted things a bit last night which improved leak rate.

I slept for 8 hours total last night but took off the mask when I was sleep after 5 hours.

---

[JoeyWallaby]

[Geer1]

Yes I have recorded myself before but not recently. I don't know about that theory, high PS was maintained by the machine on Jan 29 from 16:25 to 17:55, so a full sleep cycle.

Maybe not a different stage of sleep but I do think it is related to your brain slowing down breathing when PS goes higher, the higher PS increases your tidal flow substantially but body maintains a lowering minute vent by lowering the respiration rate. Minute vent fluctuates based on sleep stage and because these periods seem to end abruptly I figured there might be a correlation. Just looked at a few recent threads by others and it seems to happen to them as well.

I am guessing that example is just an arousal and then the machine fighting your arousal breathing. 

Do you think the pressure spikes bother you? Maybe setting a limit on PS might help if so.

[JoeyWallaby]

Well I noticed my breathing is best when the machine increases EPAP to about 5.8 and PS to about 8, so I was thinking of increasing Min EPAP to 4.4 and Min PS to 6.

[Geer1]

I think you are chasing perfection a little too much considering a jump like that. Your median PS is around 4 and you only spend around 10% to maybe 20% of night at PS of 8 which are times where your breathing is uneven or machine is pumping up pressure because your minute vent is declining. I still think some of that may be sleep stage related, deep sleep has a different type of breathing waveform that looks perfect and it also requires lower minute vent which is possibly why you find these breaths at PS of 8 to look the best. Rem on the other hand will look rough and uneven and are likely some of the moments where you see your PS levels fluctuating. Stage 2 sleep is likely when you are cruising along at min PS. Just my guesses though. 

I would probably start with 4 for a few nights then 5 and then 6, I would judge sleep more objectively as Dave and others have recommended and if you don't notice a significant improvement lower PS back to last setting (or try a spot in between). Doubling your PS is just asking for trouble especially with your past aerophagia issues.

I don't think changing EPAP will make much difference so can probably set it anywhere 4-6, lower EPAP is the lower IPAP will be so I would personally set at 4 but don't think it matters that much.

Edit: If you aren't familiar with different sleep stage waveforms you will probably find some good information watching some of TheLankyLefty27's youtube videos on scoring sleep data (there are a few good ones including one on rem sleep).

[JoeyWallaby]

I'm not chasing perfection, I keep waking up or not waking up and taking the mask off, then sleeping without and feeling terrible. I slept for 8 hours total last night and only for like an hour and a half with CPAP. I took promethazine tablet (commonly prescribed for insomnia in Australia) which might have messed up stuff apart from... you know, messing with the settings.

I'm going to back Min PS 3 and Min EPAP 4. I'm going to record myself sleeping, when I wake up during the night, it's ALMOST ALWAYS on my back. I think positioning is important and I've neglected that aspect of treatment.

[Sleeprider]

That's a really interesting pattern of alternating inspiration and expiration in the flow rate, with inspiration dark-areas related to mask pressure support. I have no idea what that is, but it might make a great quilt pattern. ;

[Geer1]

Yikes that is a mess. I believe you were over ventilated and look how low your respiration rate was, normal is 12-20. I think you were on the right path with increasing PS but you need to move slower.

What I meant by chasing perfection is that you were looking for the best looking flow rates which you determined to be at EPAP of 6 and PS of 8 then you chased that. Baby steps, collect some data and give your body time to adjust between each setting. If there is improvement try further, if there isn't step back and settle with knowing your machine is dialed in.

Recording yourself might make you realize when you appear to be getting uncomfortable. Try syncing video to CPAP data by holding breath briefly and giving a thumbs up to camera or something along those lines. What I would be curious about is if it appears that pressure spikes are causing arousal, if so limiting max ps might help.