My first night on ASV

[jskinner]

I'm more inclined to suggest:

EPAP=9.0 cm
IPAP Min=10.0 cm
IPAP Max=19.0 cm
BPM=Auto

Results: http://james.istop.com/apnea/reports/AsvNov29.pdf

I think try Snoredogs next suggestion tonight, setting BPM

[georgepds]

I finally got the point about PB. I looked up the specs on your machine and it says

"Complex Sleep Apnea occurs when a person is identified as having Obstructive Sleep Apnea but develops Central Sleep Apnea when using a CPAP machine. The cause of Complex Sleep Apnea is unknown at this time. The Bipap Auto SV sleep therapy delivers optimal therapy for complicated sleep-disordered breathing patients utilizing a multilevel algorithm"

If these statements apply to you, I now understand that PB developed as a result of using CPAP, and this machine will help to counter that problem.

https://www.cpap.com/cpap-machine/bipap ... -cpap.html

[OutaSync]

James,

Can you get a hold of a pulse-oximeter to run at the same time? I'd be interested to see how the PBs affect your O2 levels.

Bev

[jskinner]

Can you get a hold of a pulse-oximeter to run at the same time? I'd be interested to see how the PBs affect your O2 levels.

Yes I own a Nonin WristOx, I suppose I could check that out some night.

[Snoredog]

how are you feeling after a night of sleep like that?

[jskinner]

how are you feeling after a night of sleep like that?

Well defiantly better than before ASV but not as good as I had hoped. The 20th and the 25th where probably the best with respect to how I felt the next day.

I'm a bit discouraged actually. I had really hoped that ASV would take me back to the way things where when I was first on CPAP. I keep wondering if these centrals aren't a result of the small stroke like things that I experienced. My first two sleep studies before CPAP only showed 1 central but the study last Aug without CPAP showed quite a few I am told (have yet to get my hands on a copy of the report). In someways I feel like it would have been better to never have started CPAP and I might have avoided the last two years of grief, nasal problems, stroke like things, centrals... Ok just feeling sorry for myself will stop now

[Snoredog]

your sleep seems to go into the tank once you get into REM. If you look at last night's report, you did pretty good for the first 1.5 hours and before that block of central HI's you start taking some deep breaths, both peak and tidal spike up. Then right after that machine ramps up IPAP pressure. You almost have to look at that IPAP working pressure as an inverse of what is happening with your inspiration breaths.

If you look at that block of central hypopnea right before therapy hour 2, and break up that hour, my guess is that is about a 15-minute period that you were in central hypopnea. Now I'm using a Mac and its preview which allows me to view your PDF and select any aspect of therapy flags and select up/down where I can align those events to what the machine's response was. Now I'm just describing that solid red block of H's,

It shows:

1. Peak volume spiked up to over 40ml, Tidal exhale volume also spiked up to about 540 ml, rest of the night you hovered around 500ml just judging by the graph.
2. Machine sent you to backup mode peaking in BPM mode about the center of the that block of events.
3. I wasn't until IPAP working pressure tapered on down to about 13cm did that block of H's subside.
4. Then you did good for another 30-45 minutes
5. During this block of H's seen as solid red, IPAP was aggressive with its response.

Next 2 H's seen at hr 2.5, 2.6:

1. Response by machine was not at all the same, IPAP working pressure only went up by 1 cm to 11 cm, at most 12 cm. Observing
down to what Peak and Tidal were doing, they maybe came up by a few ml's that's it.
2. When I select on down to Patient Triggered Breathing the line is solid indicating those events either were NOT central or were not severe
enough to send you into the backup/BPM mode. Since there is only 2 tics, but soon after first PB tic is seen.
3. Response seen to these H's would indicate to me they were obstructive hypopnea and the machine resolved them (did not prevent, but resolved them). This is what I would expect it to do, increase IPAP to extend the inspiration breath so it met its target.

First and Second PB seen:

1. Perfectly aligned with the 2nd H seen above, is the first PB seen for the night.
2. Machines response looks like it dropped IPAP by 1 cm then increased it back up and held it for a period of time about at 13 cm.
3. No machine triggered breathing was seen, but BPM rate shot up to about 16.
4. Then again, you stabilize for another 30 to 45 minutes.
5. Not a real aggressive response was seen by the machine.

Third or Next PB seen:

1. Machine response again not real agressive, however this one is followed by a central Hypopnea.
2. The H's ended when machine went to BPM mode.
3. Again another 30-40 minute period with no events, there are however a dip to Machine triggered Breathing seen
with no residual events seen above (no Therapy flags for that blip). This would mean to me it went to BPM mode
as it seen what was a central event.

Next H's seen at Therapy hour 5:

1. Peak and Tidal volumes bounce up to 45/550 respectively, followed by a couple of double-triple H's, all appear to be central.
2. Machine drops you to Machine triggered breathing also indicating these are central, they resolve, P & T settle back down to avg.

Last event/Hypopnea seen for session:

1. Last Hypopnea also seen as central, corresponding dip in Patient Triggered Breathing seen, resolves it.

Rest of the nightly session:

1. No more therapy flags were seen after therapy hour 5.5.
2. However, if you observe the Patient Triggered Breaths line for the rest of the night until wake, you see several blips
where you went into Machine triggered breathing and NO therapy flags above. I see this meaning you are right on the
verge of having a central, the machine puts you in BPM mode to correct it and the event is avoided.

That is how I read last night's report. Is it the rapid movement of IPAP that is causing instability?
While I think it will take a few nights of fine tuning timing parameters getting IT just right, I think if you use those Fixed settings I suggested above it may stabilize your breathing just enough to prevent some of the PB being seen. Can some of those central Hypopnea be transitional centrals? They could be, they seem to be close to where you would be in REM. Machine went
while at the very end of that session with Peak and Volumes go erratic, no therapy flags, I don't
know if you are asleep there or not, but it resembles the beginning of the session where you probably
were awake.

If you observe the Breaths Per Minute graph and where the line drops down to about 10 BPM's you will see those periods
correspond with Machine triggered breathing, meaning you are not breathing or have skipped a breath.

I think the Fixed BPM may just help with some of that residual, if you follow the logic behind the titration guide they want to just slow your BPM/RR down a tiny bit. Take just a little bit longer breaths and things may stabilize. Things get quickly out of whack when you start breathing rapidly or very deeply, when you do that it seems a central will soon follow. The object behind eliminating those Centrals is to control breathing and if needed slow that breathing down before the central, that is how this machine eliminates Centrals.

Snoredog not impressed with BPM=Auto mode on this machine, machine needs an adjustable parameter where you can specify possibly a minus -3 variable to that BPM=Auto mode. So instead if it only dropping BPM rate by 2 it drops it by a selectable 3 and still picks up other timings for IT and Rise time. But I guess you accomplish the same thing by inputting the BPM=Fixed mode.

It will be interesting to see how the BPM=Fixed settings works in your case. Right now, IPAP is not pegging at any Maximum, it is not staying at the Minimum, so machine appears to have the room it needs to move and respond without being hindered by any of the settings used.

You had zero AP's last night that is good.

I think you have a very mild form of PB, this machine may be sensitive to them like the Remstar Auto is to snores:

http://ep.physoc.org/cgi/content/abstract/91/2/295

Periodic breathing is an unusual form of breathing with oscillations in minute ventilations and with repetitive apnoeas or near apnoeas. Reported initially in patients with heart failure or stroke, it was later recognized to occur especially during sleep. The recurrent hypoxia and surges of sympathetic activity that often occur during the apnoeas have serious health consequences. Mathematical models have helped greatly in the understanding of the causes of recurrent apnoeas. It is unlikely that every instance of periodic breathing has the same cause, but many result from instability in the feedback control involved in the chemical regulation of breathing caused by increased controller and plant gains and delays in information transfer. Even when it is not the main cause of the periodic breathing, unstable control modifies the ventilatory pattern and sometimes intensifies the recurrent apnoeas. The characteristics of disturbances to breathing and their interaction with the control system can be critical in determining ventilation responses and the occurrence of periodic breathing. Large abrupt changes in ventilation produced, for example, in the transition from waking to sleep and vice versa, or in the transition from breathing to apnoea, are potent factors causing periodic breathing. Mathematical models show that periodic breathing is a ‘systems disorder’ produced by the interplay of multiple factors. Multiple factors contribute to the occurrence of periodic breathing in congestive heart failure and cerebrovascular disease, increasing treatment options.

Reading your reports seems to correlate to what they are saying above.

[dsm]

how are you feeling after a night of sleep like that?

Well defiantly better than before ASV but not as good as I had hoped. The 20th and the 25th where probably the best with respect to how I felt the next day.

I'm a bit discouraged actually. I had really hoped that ASV would take me back to the way things where when I was first on CPAP. I keep wondering if these centrals aren't a result of the small stroke like things that I experienced. My first two sleep studies before CPAP only showed 1 central but the study last Aug without CPAP showed quite a few I am told (have yet to get my hands on a copy of the report). In someways I feel like it would have been better to never have started CPAP and I might have avoided the last two years of grief, nasal problems, stroke like things, centrals... Ok just feeling sorry for myself will stop now

James,

Re the Bipap Auto SV - I doubt there is another machine as tuneable as this one & also that supplies such a variety of data. Don't feel too discouraged as you are still in the getting used to phase & have yet fine tuned the machine. Take the improvements you already have & look to finely adjust around them.

The main thing though is to identify what aspect of the therapy is not optimal.

Two things that are worth looking into

1) SpO2 data - how does that match up against the data coming from the Bipap AutoSV
2) Looking for any hints of excessive CO2 blowout or retention.

You have the SpO2 meter so a few readings from that may provide some relevance to the PB scores - if SpO2 data looks good for those PB periods then look for any clues as to CO2 - (what was breathing rate during the PBs etc: )

DSM

[jskinner]

Snoredog, thanks for the detailed analysis. Will go with your suggested fixed BPM settings tonight. I might increase IPAP Min by +1cm from your recommendations as I like a little difference between EPAP & IPAP

[Snoredog]

Snoredog, thanks for the detailed analysis. Will go with your suggested fixed BPM settings tonight. I might increase IPAP Min by +1cm from your recommendations as I like a little difference between EPAP & IPAP

that is fine, use what feels the most comfortable. That won't impact the backup rate any or events seen.

[jskinner]

Results: http://james.istop.com/apnea/reports/AsvNov30.pdf

It was a bit of a rough night as I couldn't fall aleep with the fixed backup rate. However I do feel better than usual. I'm not sure if that's because I didn't sleep deeply and as a result didn't have as many events or if we are really on to something

Strangely I found 12 BPM very rushed and I was often not finished with my current breath before the next one was being forced upon me. As you can see, for the first 3 hours I was wide awake. I fiddled various with settings trying to make it more comfortable until I finally gave up and went back to snoredogs suggestioned settings. Its strange that a BPM of 12 would seem faster than what I normally breath since my average BPM has always been around 14.

I have a feeling though that this fixed BPM might lead to an improvement. Just need to find settings that are more comfortable and less disruptive. Man I wish this machine had BiFlex, I find those transitions harsh.

[Banned]

Strangely I found 12 BPM very rushed and I was often not finished with my current breath before the next one was being forced upon me.

1. Decrease BPM.
2. Increase Inspiration Time.

I find those transitions harsh.

1. Increase Rise Time (e.g. 3 to 4)

Banned

[Snoredog]

Interesting.

What IT= time did you end up using?,

think I suggested IT=2.05 seconds based upon BPM=12
If you used Rise Time=2; I would try setting 3 or 4, Rise time is more a comfort setting. You should
be able to determine if Rise Time=3 feels better within a few minutes, might be something
you experiment with while awake.

Not excited to see the fall in Patient Triggered Breathing, but you do feel better?
So these settings were less comfortable than what you have been using? Do you notice that BPM=Fixed settings right away? If so, maybe you do want to try:

BPM=11
IT=2.7
Rise Time=3 or 4.

Note: If you can tell there is a difference with breathing right away when going from BPM=Auto to BPM=Fixed, I would adjust rise time to get that comfortable first before changing IT time or BPM.

[Snoredog]

duplicate post

[Snoredog]

Here's the other 4cmH2O to 10cmH2O recommended gap Doug mentioned in his post above:

4.3.1.6 The recommended minimum IPAP-EPAP differential is 4 cm H2O and the maximum IPAP-EPAP differential is 10 cm H2O (Consensus).

http://www.aasmnet.org/Resources/Clinic ... 040210.pdf

http://www.pubmedcentral.nih.gov/articl ... id=2335396

I don't think the above consensus was meant for Complex Sleep Disordered Breathing. But
then again they also wrote:

4.2.1.2 The recommended minimum starting CPAP should be 4
cm H2O in pediatric and adult patients (Consensus).

LOL