airbreak icon indicating copy to clipboard operation
airbreak copied to clipboard

Possible improvements to PAP firmware itself.

Open Asmageddon opened this issue 4 years ago • 20 comments

For context, I am a Sleep Disordered Breathing patient, and active in a community where we discuss treatment and surrounding research.

It's a major grievance to many of us that whereas PAP machines are generally sufficient treatment in older men, younger people, women, and milder cases(where no degeneration of arousal mechanisms is present) experience only very limited benefit - of which some is inherent to the limitations of NIV, while some is regrettably down to algorithmic matters, with ResMed doing much worse than its competitor, Phillips Respironics.

Specifically, the following features would likely make a large difference:

  • Exhale Support - something similar to Phillips Respironics FLEX features, which essentially reduce pressure during exhale to alleviate expiratory overpressure buildup contributing to exhalatory intolerance without compromising the capacity of treatment to stent airways open. This would especially be important for a large share of patients who have narrow nasal cavities.
  • Pressure support waveform contour modification - while ResMed's EasyBreathe is very tolerable, it is not as effective as steeper pressure support curves, both in terms of preventing the need for the body to escalate respiratory effort, and in terms of elevating airway pressure during inhalation to maintain the capacity of treatment to stent the airway.
  • Disabling ASV mode backup rate - persistent, neurological central apnea is rare in SDB patients, whereas treatment-emergent central apneas diminish and disappear as the body adjusts to treatment, with the backup rate instead picking up post-arousal drops in ventilation caused by a drop in CO2, and preventing transition back to voluntary breathing control.
  • Making it possible to use a narrower min and max PS range in ASV mode, rather than mandating max PS to be at least min PS plus 5cmH2O

Of course, this is not a finite list, and much more could be improved, but past the above, I'm not sure if there's anything I'd guess likely to be possible to easily integrate into existing firmware via reverse engineering.

Asmageddon avatar May 14 '21 17:05 Asmageddon

Hi,

You might have observed that there has been no recent activity by the developers for a long time and as such, it seems that the project is practically abandoned. I had contacted one developer 8-9 months ago and he told me that there was no real reason to go on with the project as the main aim was to prove that a CPAP unit can be used as a ventilator in an emergency situation (and they did prove that by the modification) and also the projected ventilator shortages never happened. Altering the main firmware for other purposes, like enabling other modes, would probably create legal troubles for them (copyright issues and also potential harm to patients using these mods). Of course, new developers can always continue from where they left, but from what I have observed in the last 9 months, there is very little to almost no interest in the project. (I don't want to create an air of negativity and would be very happy to see some more activity but that seems to be the truth for now).

The exhale support already exists in Res Med 10 devices, however it is limited to 3 choices (1-3 cm H20). As such, it is a limited form of BiPAP. If you want more flexibility, then the manufacturer wants you to buy their BiPAP device...

Drmaestro avatar May 14 '21 18:05 Drmaestro

Hi @Drmaestro, thanks for the reply. The airbreak project already does unlock all modes, a feature I've taken advantage of. Unfortunately, the Expiratory Pressure Relief feature is not actual exhale support, but rather a limited form of pressure support(which is essentially inhale support). I already run my device in bilevel mode, but... it's not really enough for my case, nor for the cases of many other people. The worse nasal breathing, the more EPAP is needed, and the less EPAP can be tolerated. I had high hopes for ASV, but the backup rate just hurts the efficacy so badly.

Ultimately, PAP is merely management, and the ultimate goal is skeletal surgery(and/or whatever adjunct surgeries are necessary), but not everyone has access to such treatment. Improving the algorithms on ResMed devices could potentially save the lives of at least a few of the people I know from inescapable fatigue.

Asmageddon avatar May 14 '21 18:05 Asmageddon

Hi @Drmaestro, thanks for the reply. The airbreak project already does unlock all modes, a feature I've taken advantage of. Unfortunately, the Expiratory Pressure Relief feature is not actual exhale support, but rather a limited form of pressure support(which is essentially inhale support). I already run my device in bilevel mode, but... it's not really enough for my case, nor for the cases of many other people. The worse nasal breathing, the more EPAP is needed, and the less EPAP can be tolerated. I had high hopes for ASV, but the backup rate just hurts the efficacy so badly.

Ultimately, PAP is merely management, and the ultimate goal is skeletal surgery(and/or whatever adjunct surgeries are necessary), but not everyone has access to such treatment. Improving the algorithms on ResMed devices could potentially save the lives of at least a few of the people I know from inescapable fatigue.

I have followed the instructions to unlock the ASV and other modes, but the parameters in the menu are incomplete and some of them cannot be set, did you solve this problem? (trigger, cycle, Backup rate, etc)

zhuhongchao avatar Jun 27 '21 15:06 zhuhongchao

The ASV mode doesn't allow configuring trigger and cycle, and I believe the backup rate setting is for iVAPS, not ASV, in which backup rate is mandatory. I've personally not had success with the unlocked ASV mode. I'm not certain if it's bugged, or just bad. I've seen similar failures on its part on actual ASVs people have had.

Asmageddon avatar Jun 30 '21 09:06 Asmageddon

Asmageddon, I am an SDB sufferer as well, RERAS, not apneas, and I was hoping to use this firmware to be able to fiddle with the EPAP beyond the EPR of 3 for the Airsense 10. Would it accomplish this? It appears that I need an IPAP of near 15 for REM sleep, less during the rest of the night, and I would like to have an EPAP of near 6.

Thanks!

jlm255 avatar Sep 20 '21 04:09 jlm255

Trigger and cycle are for BiPap modes:

https://www.youtube.com/watch?v=ts9lNJ2g1IE

chuckhacker avatar Nov 14 '21 04:11 chuckhacker

I've recently come back around to this idea, particularly hoping to disable the ASV mode backup rate for personal use, which I hope could help me address my horrible residual sleep fragmentation on BiPAP modes.

@osresearch @wormyrocks @colinoflynn If you could help me with any of the notes not uploaded to this project's github, or pitch some ideas about how I could possibly approach debugging a running device to identify the code path or variable responsible for this, I would be deeply grateful.

Asmageddon avatar Apr 23 '22 09:04 Asmageddon

Hi, I am sufferer of same sleep fragmentation and been wringing my machines out and closely looking at algorithms. As well as an AS10 I have an interesting machine I have not seen many investigating yet. It is a Lowenstein Prisma 20a. I believe you may be starting with an inferior base for all your efforts. The Prisma is equipped with way better hardware and design IMO. The algorithms are way better as well. The company has built its knowledge and I believe it algorithms on hospital ventilators and it shows. A base model APAP/CPAP offers 3 comfort setting which leverage bilevel and trilevel modes of higher models. The most interesting is the trilevel which they call softpap 3. This mode gives pressure support of 4 and switches up the algorithm as different stages are reached in pressure. Also the algorithm delivers ipap pressure by the time inspiration begins not mid-way or even at the end like Resmed and others. This makes a difference in smoother delivery at more appropriate times which benefits narrow nasal cavities rather than the late rush of air which just aggravates as pressures rise. The company has a flashing tool and all models in a range have one firmware. You can see the vacant menu locations. Parts of higher modes are used for comfort provision on lesser models.

macka-the avatar Feb 05 '24 10:02 macka-the

Sounds intriguing, where/how can I get one? I just buy my machines, going through insurance is a nightmare.

On Mon, Feb 5, 2024 at 2:45 AM macka-the @.***> wrote:

Hi, I am sufferer of same sleep fragmentation and been wringing my machines out and closely looking at algorithms. As well as an AS10 I have an interesting machine I have not seen many investigating yet. It is a Lowenstein Prisma 20a. I believe you may be starting with an inferior base for all your efforts. The Prisma is equipped with way better hardware and design IMO. The algorithms are way better as well. The company has built its knowledge and I believe it algorithms on hospital ventilators and it shows. A base model APAP/CPAP offers 3 comfort setting which leverage bilevel and trilevel modes of higher models. The most interesting is the trilevel which they call softpap 3. This mode gives pressure support of 4 and switches up the algorithm as different stages are reached in pressure. Also the algorithm delivers ipap pressure by the time inspiration begins not mid-way or even at the end like Resmed and others. This makes a difference in smoother delivery at more appropriate times which benefits narrow nasal cavities rather than the late rush of air which just aggravates as pressures rise. The company has a flashing tool and all models in a range have one firmware. You can see the vacant menu locations. Parts of higher modes are used for comfort provision.

— Reply to this email directly, view it on GitHub https://github.com/osresearch/airbreak/issues/51#issuecomment-1926694463, or unsubscribe https://github.com/notifications/unsubscribe-auth/AIQNKXTQ73Y4J7EPG7EX5RDYSCZ4TAVCNFSM444243P2U5DIOJSWCZC7NNSXTN2JONZXKZKDN5WW2ZLOOQ5TCOJSGY3DSNBUGYZQ . You are receiving this because you commented.Message ID: @.***>

--

Jeff Mason

jlm255 avatar Feb 05 '24 18:02 jlm255

I am in Australia, we have to buy our machines. Problem is some of these companies come from hospital ventilator and associated equipment industry IMO. There is a lot of price gouging going on, maybe because of the Insurance model in other countries as well. Government health is huge business. Look up the ventilator contracts Phillips had with US gov. Money thrown at them and then the abuse is incredible. Anyway, you can get the German made Prisma in Australia and Europe, but the cheapest by far is if you can get one out of India. I would like to get my hands on the PrismaLab. It is the top model with every mode. It has real time data monitoring and ability to control via network with smoothed transitions so a sleep tech can move you between modes without disturbing you. The Lowenstein machines are unavailable in the US. They are far superior IMO. They are being kept out by FDA I believe, must have not greased the right palms.

macka-the avatar Feb 06 '24 02:02 macka-the

Dang that sucks. I'd like to get your contact info somehow.

I bought a Resvent from China because I wanted to try volume assured (iVaps EVaps whatever). It basically keeps my pressures near 4 but somehow forces a breath if my breathing drops below a set value. This seems to be just as effective or more so, but what I think I am finding is that my deep sleep requires different values than REM so a better algorith or sleep tech to figure things out sounds great.

I have had UPPP surgery, MMA surgery, and 2 rounds of tongue radiofrequency ablation and I think my apneas are cured but without a doubt I still have some strange breathing problem. After all the surgeries, I tried going without CPAP for a month and eventually things were going downhill again.

My sleep and life have improved a lot. Before all this my life was really really in a dark spot. Everything was falling apart (job / family / etc)

On Mon, Feb 5, 2024 at 6:36 PM macka-the @.***> wrote:

I am in Australia, we have to buy our machines. Problem is some of these companies come from hospital ventilator and associated equipment industry IMO. There is a lot of price gouging going on, maybe because of the Insurance model in other countries as well. Government health is huge business. Look up the ventilator contracts Phillips had with US gov. Money thrown at them and then the abuse is incredible. Anyway, you can get the German made Prisma in Australia and Europe, but the cheapest by far is if you can get one out of India. I would like to get my hands on the PrismaLab. It is the top model with every mode. It has real time data monitoring and ability to control via network with smoothed transitions so a sleep tech can move you between modes without disturbing you. These are unavailable in the US. They are far superior IMO. They are being kept out by FDA I believe, must have not greased the right palms.

— Reply to this email directly, view it on GitHub https://github.com/osresearch/airbreak/issues/51#issuecomment-1928674542, or unsubscribe https://github.com/notifications/unsubscribe-auth/AIQNKXSCR75XWPDM276E7RDYSGJJPAVCNFSM444243P2U5DIOJSWCZC7NNSXTN2JONZXKZKDN5WW2ZLOOQ5TCOJSHA3DONBVGQZA . You are receiving this because you commented.Message ID: @.***>

--

Jeff Mason

jlm255 avatar Feb 06 '24 05:02 jlm255

I think for the first half the night I'm better off without the CPAP. But then the REM half I need it desperately.

On Mon, Feb 5, 2024 at 6:36 PM macka-the @.***> wrote:

I am in Australia, we have to buy our machines. Problem is some of these companies come from hospital ventilator and associated equipment industry IMO. There is a lot of price gouging going on, maybe because of the Insurance model in other countries as well. Government health is huge business. Look up the ventilator contracts Phillips had with US gov. Money thrown at them and then the abuse is incredible. Anyway, you can get the German made Prisma in Australia and Europe, but the cheapest by far is if you can get one out of India. I would like to get my hands on the PrismaLab. It is the top model with every mode. It has real time data monitoring and ability to control via network with smoothed transitions so a sleep tech can move you between modes without disturbing you. These are unavailable in the US. They are far superior IMO. They are being kept out by FDA I believe, must have not greased the right palms.

— Reply to this email directly, view it on GitHub https://github.com/osresearch/airbreak/issues/51#issuecomment-1928674542, or unsubscribe https://github.com/notifications/unsubscribe-auth/AIQNKXSCR75XWPDM276E7RDYSGJJPAVCNFSM444243P2U5DIOJSWCZC7NNSXTN2JONZXKZKDN5WW2ZLOOQ5TCOJSHA3DONBVGQZA . You are receiving this because you commented.Message ID: @.***>

--

Jeff Mason

jlm255 avatar Feb 06 '24 05:02 jlm255

The company has a flashing tool and all models in a range have one firmware. You can see the vacant menu locations. Parts of higher modes are used for comfort provision.

Wait, are you saying the prisma devices are hackable by default?

Anyway, I've experimented with both trilevel and with fasted PS rise time in my custom firmware, the problem with fast rise time is that it becomes almost impossible to detect the actual end of breath, so you end up causing horrid asynchrony, and I wasn't able to solve this problem. Trilevel actually improves comfort, but also has some challenges.

I'm rather interested in Prisma's rapid pressure response due to a valve-based design, but if they solve the two above issues, their devices might actually be great.

Asmageddon avatar Feb 17 '24 06:02 Asmageddon

Wait, are you saying the prisma devices are hackable by default?

Maybe, all I know is anyone can see the link to firmware updates for every model and a link to a flashing tool of some type. There is an unused micro usb port on the machine. Communications modules are available. I have a lower end model and it has bi-level and trilevel function masquerading as comfort features. The menus have lots of spare spaces and all models in that one range share user & service manuals. Don't know what protections are at chip level but the service manual says to enter service mode and simply enter serial number on side of machine when performing a mainboard replacement. When studying the mask pressure trace against your flow rate in software like Oscar, I believe I am seeing more refined algorithm sets than Resmed. The valve based design you mentioned allows them to utilize the spooled air potential in a more logical and sophisticated way.

macka-the avatar Feb 17 '24 09:02 macka-the

How fast is fast? I'm currently using 900ms

On Fri, Feb 16, 2024 at 10:42 PM Asmageddon @.***> wrote:

The company has a flashing tool and all models in a range have one firmware. You can see the vacant menu locations. Parts of higher modes are used for comfort provision.

Wait, are you saying the prisma devices are hackable by default?

Anyway, I've experimented with both trilevel and with fasted PS rise time in my custom firmware, the problem with fast rise time is that it becomes almost impossible to detect the actual end of breath, so you end up causing horrid asynchrony, and I wasn't able to solve this problem. Trilevel actually improves comfort, but also has some challenges.

I'm rather interested in Prisma's rapid pressure response due to a valve-based design, but if they solve the two above issues, their devices might actually be great.

— Reply to this email directly, view it on GitHub https://github.com/osresearch/airbreak/issues/51#issuecomment-1949822340, or unsubscribe https://github.com/notifications/unsubscribe-auth/AIQNKXUNUAOPRMBVKR3L2HTYUBGNVAVCNFSM444243P2U5DIOJSWCZC7NNSXTN2JONZXKZKDN5WW2ZLOOQ5TCOJUHE4DEMRTGQYA . You are receiving this because you commented.Message ID: @.***>

--

Jeff Mason

jlm255 avatar Feb 17 '24 23:02 jlm255

My breathing slows down too much during sleep so I have back up breathing rate, fiddling with rise time, and the length of time CPAP machine waits to increase pressure to try to force a breath (on resvent they label it Ti which is confusing) I was wondering if instead of doing this, what if we breathed more concentrated oxygen. Would this make up for the slow breathing rate? Thoughts please.

On Sat, Feb 17, 2024 at 1:02 AM macka-the @.***> wrote:

Wait, are you saying the prisma devices are hackable by default?

Maybe, all I know is anyone can see the link to firmware updates for every model and a link to a flashing tool of some type. There is an unused micro usb port on the machine. Communications modules are available. I have a lower end model and it has bi-level and trilevel function masquerading as comfort features. The menus have lots of spare spaces and all models in that one range share user & service manuals. Don't know what protections are at chip level but the service manual says to enter service mode and simply enter serial number on side of machine when performing a mainboard replacement

— Reply to this email directly, view it on GitHub https://github.com/osresearch/airbreak/issues/51#issuecomment-1949907826, or unsubscribe https://github.com/notifications/unsubscribe-auth/AIQNKXUVIOSSREM3N2OXY6TYUBWZDAVCNFSM444243P2U5DIOJSWCZC7NNSXTN2JONZXKZKDN5WW2ZLOOQ5TCOJUHE4TANZYGI3A . You are receiving this because you commented.Message ID: @.***>

--

Jeff Mason

jlm255 avatar Feb 17 '24 23:02 jlm255

Unless you have neurological sleep apnea, do not enable backup rate. If your body pauses breathing, it's doing it because you are OVER-ventilated. Breathing is supposed to be slower and shallower during sleep.

Also, lack of oxygen is not the problem. The problem with sleep disordered breathing is the sleep fragmentation caused by the body's reaction to escalating airway resistance. Oxygen doesn't matter much.

Asmageddon avatar Feb 18 '24 08:02 Asmageddon

I would have said the same thing, but recently I was reading this guys blog and it rocked my world:

https://www.cpaphealthissues.com/2019/06/ideal-body-weight-cpap-bilevel.html

I am someone who has never registered an AHI over 2 (on the CPAP) from before my sleep apnea diagnosis, and through surgeries, and to the present day. My sleep lab test showed an AHI of 7 and an RDI of 30. So in general my obstructions have always been pretty minimal, but it has been fragmenting the hell out of my sleep since birth. If you look at my fitbit data, which I know isn't perfect, you can see how fragmented my sleep is.

My pressures are usually from 4 to 6, I actually think that a pressure of 2 might be enough for me, but very hard to find a CPAP that goes that low. There is no question in my mind that when the CPAP is blowing air into me like crazy that it also fragments my sleep.

While I am not positive yet, fiddling with Ti and breathing rates etc does seem promising. I have had some phenomenal days where I didn't know it was possible to feel so happy. But I can't get it to 7 days a week. I would say on average I can get one "perfect" day a week, 5 very functional days, and 1 day where I am very "off" and sometimes "barely surviving" but it seems like those days are getting less frequent as I seem to be honing in on which numbers will really prevent a disastrous night.

On Sun, Feb 18, 2024 at 12:12 AM Asmageddon @.***> wrote:

Unless you have neurological sleep apnea, do not enable backup rate. If your body pauses breathing, it's doing it because you are OVER-ventilated. Breathing is supposed to be slower and shallower during sleep.

Also, lack of oxygen is not the problem. The problem with sleep disordered breathing is the sleep fragmentation caused by the body's reaction to escalating airway resistance. Oxygen doesn't matter much.

— Reply to this email directly, view it on GitHub https://github.com/osresearch/airbreak/issues/51#issuecomment-1950999500, or unsubscribe https://github.com/notifications/unsubscribe-auth/AIQNKXRHIQ5NPUPOA4F26ATYUGZYPAVCNFSM444243P2U5DIOJSWCZC7NNSXTN2JONZXKZKDN5WW2ZLOOQ5TCOJVGA4TSOJVGAYA . You are receiving this because you commented.Message ID: @.***>

--

Jeff Mason

jlm255 avatar Feb 18 '24 20:02 jlm255