Welcome to Apnea Board !
As a guest, you are limited to certain areas of the board and there are some features you can't use.
To post a message, you must create a free account using a valid email address.
Login or Create an Account
How does increasing the PS 'remind' you to breathe? Is that not just lowering the EPAP?
I just experimented a bit with my Aircurve, adjusting the Ti Min and Max settings after reading another thread where someone said they didn't like the feeling of the inhale dropping off into exhale so quickly. So I tried changing the trigger, cycle, and Ti Min and Max to see if I could smooth out that drop off and let the inhale last a bit longer, and I think it feels a bit better. I set the IPAP to 9 and EPAP to 5 and I think it felt okay. But it's hard to say if the centrals will happen when I sleep or not. Is that something that you can get used to and get rid of over time?
I'm not sure but I may try to experiment with that for a few nights after not using it for over a month, and see if I can find something that works. If it seems like the BIPAP with PS above 3.0 isn't working for me and is causing centrals then I may think about ASV...Because if centrals are the main problem then it might be the answer. I have a really strong suspicion that IPAP of 9-11 is probably my sweet spot but I can't tolerate it at the moment with EPR 3 on the Autoset, or PS above 3.5 causing centrals with the Aircurve. But tweaking the other settings may make a bit of a difference with that imbalanced feeling.
Quote:How does increasing the PS 'remind' you to breathe? Is that not just lowering the EPAP?
EPR subtracts pressure from IPAP, PS adds pressure to EPAP
Autoset controls IPAP (Pressure), BiLevel controls EPAP
Quote:I just experimented a bit with my Aircurve, adjusting the Ti Min and Max settings after reading another thread where someone said they didn't like the feeling of the inhale dropping off into exhale so quickly. So I tried changing the trigger, cycle, and Ti Min and Max to see if I could smooth out that drop off and let the inhale last a bit longer, and I think it feels a bit better. I set the IPAP to 9 and EPAP to 5 and I think it felt okay. But it's hard to say if the centrals will happen when I sleep or not. Is that something that you can get used to and get rid of over time?
Ti Min and Max settings are available of a BiLevel, they help to tune to your breathing rate.
Trigger and Cycle are available on a VAuto and modify how quickly or gently the pressure rises and falls between EPAP and IPAP
Trigger Sensitivity can be increased to initiate a rise to IPAP pressure on less effort by the user. At times this seems to help with Ideopathic Central Apneas.
Cycle sensitivity can be decreased to delay or increased to expedite the drop back to EPAP pressure.
Central Apneas may (In most users they do not) develop with the increased efficiency of higher PS (EPR) causing increased clearing or washout of CO2 from your blood to below your apneic threshold thus causing a Central Apnea. Over time, 2-3 months, it is likely that your body will reset your apneic threshold and eliminate those central apneas.
Gideon - Project Manager and Lead Tester for OSCAR - Open Source CPAP Analysis Reporter
I just wanted to elaborate on Bonjour's point about patience as your apneic threshold adjusts. In the image attached, you can see me inching up PS but encountering a lot of swings in my CA index, which I found fairly wearing. I finally backed off to 4.8 on Feb 12. I still saw swings, but a little less wild, and then starting around May 12, the CAI has been consistently under 1, with but 2 exceptions.
Sorry, I didn't answer your first question, How does PS 'remind' you to breathe?
First realize that this breathing system of ours operates at extremely low pressures, 20 cm of water the max pressure a CPAP can produce, is just 0.28 psi. Most people operat at about half of that or 0.14 psi. The system detects an increase in flow, the start of a breath and thus triggers the increase in pressure via PS. From there physics takes over and air is moved and frequently your body gets the hint and helps the inhalation along. You can see this on an ASV where the max PS is not reached because your body picks up the difference. An ASV needs the freedom to us very high PS to headoff events, and it does do an excellent job of it.
Gideon - Project Manager and Lead Tester for OSCAR - Open Source CPAP Analysis Reporter
It sounds like you have tried adjusting settings but still don't understand what these settings do so haven't been able to logically fine tune the settings.
EPAP = exhalation pressure
IPAP = inhalation pressure
EPR and PS = IPAP-EPAP.
As Bonjour mentioned Autoset with EPR you set IPAP and EPR subtracts from it to give EPAP. On aircurve you set EPAP and PS adds to it to give IPAP.
IPAP and EPR are the only settings available on autoset.
These machines use your spontaneous breathing to determine when to apply pressure.
On the autoset you have no adjustments for this but on the vauto you having timing controls (Timin, Timax, trigger sensitivity and cycle sensitivity).
The first one that comes into play is trigger sensitivity. The higher the trigger sensitivity the earlier the machine will start increasing pressure, if you feel the machine is providing air too early you need to lower this sensitivity, if you feel it is too slow you need to increase it.
The next one is Timin, Timin forces the machine to hold IPAP for a certain amount of time = Timin. If Timin = 0.5 seconds the machine will maintain IPAP for 0.5 seconds regardless of whether you try to breath out during that time (which would normally trigger a return to EPAP). This most likely has no effect on yourself as I don't believe you have short breaths and this setting trying to force you to hold longer breaths likely has little effect.
Next is Timax, Timax forces the machine to cycle back to EPAP after a certain amount of time = Timax. This is used in people that spend too much inhaling and forces the machine to cycle to EPAP which encourages you to breath out. Again I do not believe this is needed or would have much affect as your breathing is fairly normal with only the odd flow limitation.
Finally you have cycle sensitivity. The faster the cycle sensitivity the earlier the machine changes from IPAP to EPAP. Like trigger sensitivity key to understand is that these settings don't affect how fast the machine changes, it just affects how early or late the machine changes this pressure. If you feel like the machine is cutting off your breath and forcing you to exhale decrease cycle sensitivity. If you feel the pressure is holding too long making it hard to exhale increase cycle sensitivity.
Resmed's easybreathe waveform is the same shape regardless of the above settings. These settings just move the inhale/exhale portions closer or further apart depending on how you set the above timing controls. The only other thing that affects the waveform is EPR or PS. The higher the EPR/PS the larger the difference between EPAP and IPAP and the faster the air will flow when breathing in or exhaling.
This faster air flow is what helps overcome narrow airways/flow limitations which is why higher EPR/PS is the only setting that will help you if you have UARS. The timing controls are just to try and make the breathing comfortable. One thing to note is your breathing is slightly different when asleep than awake so how the machine feels when you are awake doesn't necessarily mean how your body will react to it when asleep. Setting the machine so it feels comfortable when awake is a good starting point, then you should adjust the timing controls slightly in each direction and see if it has any affect on your results when sleeping.
Vauto is the same as autoset, it just uses PS formula (PS + EPAP) instead of EPR formula (IPAP - EPR) and has timing controls. ASV is effectively a vauto without timing controls that adjust PS to try and maintain 90% of recent minute ventilation. If your minute ventilation graph is remaining steady ASV will make little difference other than losing timing controls. If your minute ventilation graph drops at times then what would happen during those times is ASV would increase PS to try and maintain 90% of recent ventilation. This higher PS can cause people discomfort in breathing or aerophagia because it is literally trying to force you to breath when your body doesn't want to.
ASV has one more feature, that being backup rate. Backup rate is simply the amount of time that the machine will wait if you are not trying to breath (whether or obstructive or central) before it tries to force you to breath. This helps treat central apneas and at times can help overcome obstructive apneas.
Central apneas can be caused by a number of things, if they are only present when on CPAP then they are what is called treatment emergent. Treatment emergent central apneas are caused by too efficient of carbon dioxide removal. Carbon dioxide is what regulates our breathing process, if your carbon dioxide is below what is called the apneic threshold then your body does not believe it needs to breath which causes a central apnea. This actually isn't really an issue unless it causes a drop in oxygen levels that affects your sleep. The key point here is that our breathing process is meant to supply oxygen but it regulates itself through carbon dioxide levels so at times when the brain isn't reacting to CO2 levels properly it can mess up O2 levels and cause issues but this is mostly in higher numbers or long central apneas. Treatment emergent central apneas are more common at higher PS/EPR because higher PS/EPR more efficiently evacuates CO2 making the brain think it has to breath less. Over time your body will realize that it is hurting itself by doing so and it will often adjust the apneic threshold and people will stop having treatment emergent central apneas, this usually takes a few months. In some people this doesn't correct itself and treatment emergent central apneas remain an issue and more steps are required if a higher PS is required.
Hopefully this helps understand things a bit more. The basics are quite simple, the key is to understand them and not just make changes for the sake of making changes. Based on what you are saying it sounds like you should be trying a normal trigger sensitivity and perhaps a low cycle sensitivity. Trying higher PS is the only thing that will treat your UARS and higher PS is the only thing that ASV offers that would possibly treat your UARS, this is already available to you on vauto so why buy an ASV? If you think this is actually UARS increase PS, find the most comfortable timing controls and give your body weeks/months to adjust. If you are feeling/sleeping worse because of central apneas then it could possibly be worth considering ASV but the chances of it helping are slim imo. If you are feeling/sleeping worse and aren't having central apneas then it means that UARS/restrictive airways is not the problem.
Ok thank you for the detailed explanation. I definitely needed that.
I will try to understand all of that and come up with some settings that I think will work for me. What I’m currently doing with the autoset seems to be working sometimes, but I’m still waking up a bunch of times per night and not feeling great. But it’s been a bit better than previous months with Bilevel or no PAP therapy. I’ve been doing 8-8.4 pressure with 3 EPR on the autoset. I think I’m going to experiment with the Aircurve at 9 IPAP and 5 EPAP, 4 PS. I previously had trouble with pressure support higher than 3....even like 3.4 made my breathing feel imbalanced and one night when I tried 3.6 I had a series of centrals. But I’ll give it another try and see if I can sleep a bit with it. I think changing cycle and trigger might help if I can find something that works. Because there’s definitely been something about the timing of inhale and exhale on the aircurve that feels unnatural, compared to the autoset that feels totally seamless.
Something that may be of interest to you are my own results the past few weeks. I have now been on the Candibactin and NAC supplements for 4 weeks and have been dairy free for 3 weeks. I have reintroduced a number of foods back into my diet and have the odd upset stomach still but overall digestion has improved a fair bit. I am still having very limited consumption of wheat/gluten but am starting to work it back in and planning on hitting it hard tonight with my first pasta meal in months.
I am not sure if it is one of the supplements, being dairy free, having been eating healthier the last 3 months or a combination of all the above but I am starting to feel a bit better in every regard. Very slowly but I am sure something has me on the right track. A few months ago I didn't even feel like I was capable of working full time anymore and was considering asking my boss to decrease hours. Last week I put in some overtime and worked 50 hours without feeling too bad.
My nasal congestion is improving. There are some nights I have forgotten to take my Dymista now because it doesn't bother me as much. My congestion used to kick in almost every night before I would fall asleep and this would remind me to use nasal spray but now it doesn't happen as often which is why I sometimes forget spray.
One of my physical issues was what felt like plugged ears. Ears have been tested numerous times and no issues found, I believe the issue is something related to lymph nodes, parotid gland or possibly TMJ joint perhaps some sort of mild inflammation (no obvious swelling or sharp pains as is most common with issues in those areas). Doctors have never been able to explain it even though it had been slowly getting worse and more frustrating. It is now slowly getting better.
I have had a kind of wart looking growth on my one finger that has been there for 1.5 years now. We have tried freezing it with nitrogen probably a dozen times. I used actikerall (salicylic acid and topical chemotherapy drug used for cancerous growths and stubborn warts) for a couple of months until the finger was getting raw and sore and still whatever it was wouldn't die/heal. It is now probably 60% healed on its own over these past few weeks.
My sleep is still disturbed. As much if not more than it used to be. I am struggling to sleep more than 7 hrs and still don't feel refreshed in the morning yet I feel better all around and haven't been as fatigued. I believe my sleep quality and even my "apnea" /breathing is a side effect of whatever my underlying issue is.
I see three possible reasons for improvement.
1) Dairy intolerance could have been disrupting digestive system in turn affecting both immune and neurological systems. What I believe could best be considered a form of "Chronic Fatigue Syndrome".
2) Some sort of unknown infection. I had been on antibiotics before and they didn't help but maybe the antimicrobials I am on now are fighting something in a different way. The antimicrobials are known to help with viruses and fungals unlike antibiotics so maybe something along those lines.
3) The NAC may be supporting a previous deficiency or giving me a necessary boost. NAC is a precursor to glutathione which is a powerful antioxidant that strengthens the immune system.
Whatever it is (maybe a combination of them all) I am certain it is helping. I was supposed to finish my antimicrobial treatment but am going to extend it another 3 weeks in case it is what is helping. My doctor hasn't been of much use in trying to understand this, I talk to dietitian in just over a week and am curious what she will think. I think digestive system health was part of the problem and will be asking her about trying probiotics and possibly supplemental enzymes to see if that causes further improvement.
Anyways just some food for thought. I thought sleep apnea and in general sleep disturbances were my issue for a few months, in fact the main reason I tried the diet and found this stuff out was because my sleep study got delayed indefinitely thanks to covid (still haven't had it) and this was one of the few things I could try.
If there are any questions about digestive health I would seriously consider trying some elimination diets to see if anything seems to help. You may be like me and not even realize how much of a mess your guts are and only think they are bad when they are really bad.
Put flow rate and mask pressure graphs beside each other and zoom in on individual breathes. You should be able to compare the autoset data to vauto data this way (see how soon the pressure seems to increase and if it takes longer on autoset then lower trigger sensitivity on vauto), if pressure seems to decrease earlier then lower cycle sensitivity. The data can help you adjust settings to try and match as much as possible.
It’s definitely possible I could have some dietary issues. I’ve mainly only noticed IBS symptoms appear seemingly randomly over the past 6 months, usually connected to what seems to be some particularly bad sleeps that are full of stress and anxiety. And then the symptoms disappear sometimes for months or weeks at a time. I experienced it recently for about a week, but it was like two months earlier that I previously experienced it. And I don’t think anything unusual changes with my diet.
I’m being a bit more conscious about probiotics right now, and I’ve been cutting back on cheese, but it’s hard to say if that’s related. It’s possible that bread or gluten could be an issue but I don’t think that’s ever been a problem for me before. I went keto back in November when I first started having really bad sleep, and it didn’t seem to help, but I was also very early in my journey of learning about SDB and all of this stuff so I may not have been paying attention to certain things. I’d really rather not cut out bread right now but it might be worth exploring. It’s just already difficult as it is trying to make food for myself sometimes when I’m tired or depressed and I don’t really feel like cooking special meals and shopping all the time.
I am sure there’s some kind of mind/body connection to my sleep issues, but it also seems to coincide with breathing. Like last night I woke up a few times feeling like I was suffocating. One time in particular I remember specifically, and when I checked the Oscar data in the morning there was an OA event at that specific time. It’s just so tricky for me to figure out because there are so few “events” for me, and even a lot of my awakenings seem to be so subtle without a ton of noticeable irregularities in the data, but I am sure that’s what’s happening a lot of the time because I either wake up gasping with my heart racing, or I catch myself snoring myself awake. I can feel the resistance in my soft palate area, even when I breathe while I’m awake sometimes. And my awakenings seem to become more frequent when my nose becomes more congested, and reduce when my nose is more clear. And one of the nights I slept without the CPAP I recorded the audio of myself and I was snoring steadily all night. And any time I have a decent sleep for whatever reason, a lot of my daytime symptoms disappear. I would love it if I could just get the Aircurve to work enough for me to sleep through the night and then all of the elaborate sleep hygiene and diet/supplement crap I’ve been doing every day will become less important.
If it is an intolerance simply cutting back wont help. You need to go for weeks without the offending food. The thing about intolerances is that they mess up the digestive system balance and that is why it can take weeks to notice differences because your body needs to start fixing itself to get back to normal. Probiotics are a grey area, they help some people and cause issues in others. The whole digestive system is very complex and different for everyone. That is why there are no good tests and so hard to diagnose these things, all you can really do is elimination diets.
Have you tried a full face mask? Definitely should if you have congestion. I got both the F20 and F30, prefer the F20.
Congestion can be related to histamine which is a neurotransmitter which also affects sleep. As I mentioned earlier in this thread it can be hard if not impossible to know what is causing what. It could be the sleep or it could be that your sleep is worse when everything else is worse (as I believe mine is).
