[Treatment] CO2 and Central Apneas

[Steven]

I began my own research by closing off certain openings and controlling the remaining openings to slow down flow rate but keep pressure settings, thereby lowering O2 and increasing CO2. I was aware of going too far and getting into trouble, but have been able to survive and see on my SD card data that the CAs came down below 5, OAs controlling around 5 also based on pressures. I'm still tweaking settings trying to get good readings and be comfortable. I have a Dr. appt. in a week and will discuss (and I’m sure get reprimanded) but has anyone else got any info on this ? Thanks for any ideas and suggestions.

Dscbk

Well, there has to be a way to cull the idiots out of the herd.

[dscbk]

Went to my dr. appt. He was justifiably horrified initially that I was changing my pressure settings without him, and then in amazement that I was also closing off some of the mask vents, but when he saw the results, he listened to me and agreed to do an overnight portable oximetry to make sure I was getting enough O2. I think he knew I wasn't going to comply with his normal instructions.

Just got the verbal results back from the oximetry and they said it was excellent. So I'm getting good O2 saturation, and AHI is about 5 (which is down from 35 where I started) which is still 50/50 centrals to obstructives. My settings are 17/16 on my bipap. I'm going to continue to tweak my settings and tweak my mask as long as my numbers stay good. Hopefully I'll start to actually feel a difference due to better sleep.

So I'm still sticking to my theory that the normal mask port designs and xpap machine contol schemes on pressure vs. flow rate generates high flow rates thru the masks which provides high O2 concentrations, but on the flip side can cause higher CAs for susceptible individuals due to CO2 blood level threshholds that are affected.

[greatunclebill]

to believe this, i would have to hear it personally from my doctor and not rely on a posting on the internet from a stranger. sorry, nothing personal, i'm a natural born skeptic.

apparently you heard it from your doctor. good for you.

[Netskier]

Went to my dr. appt. He was justifiably horrified initially that I was changing my pressure settings without him, and then in amazement that I was also closing off some of the mask vents, but when he saw the results, he listened to me and agreed to do an overnight portable oximetry to make sure I was getting enough O2. I think he knew I wasn't going to comply with his normal instructions.

Just got the verbal results back from the oximetry and they said it was excellent. So I'm getting good O2 saturation, and AHI is about 5 (which is down from 35 where I started) which is still 50/50 centrals to obstructives. My settings are 17/16 on my bipap. I'm going to continue to tweak my settings and tweak my mask as long as my numbers stay good. Hopefully I'll start to actually feel a difference due to better sleep.

So I'm still sticking to my theory that the normal mask port designs and xpap machine contol schemes on pressure vs. flow rate generates high flow rates thru the masks which provides high O2 concentrations, but on the flip side can cause higher CAs for susceptible individuals due to CO2 blood level threshholds that are affected.

This is a fascinating thread. Thanks for starting and continuing it.

[clipper]

I'll have to check leak rate numbers, but am pretty able to notice when it is leaking somewhere.

Yes, I'm blocking the vent ports and anti-asphyxia valve but leave an open nasal port open. This reduces the high flow rate through the mask but still leaves a small flow rate/anti asphyxia port to build up CO2 concentration.

That leads to my next question: is there an XPAP machine that hooks an O2 sat sensor into the machine and records it on the data card with the rest of the data ? That is what I really need to make sure I'm not reaching dangerous CO2 levels.


Thanks for any info.

I think it would be useful to determine if the CAs are correlated to drops in blood oxygen. If the CAs are not producing appreciable drops then, not a problem.
If the object is to raise carbon dioxide levels through PAP modification the vent should be moved some distance from the mask to produce a percentage of re-breathed air. This could be roughly calculated using the mask and hose volumes. Restricting the leak rate is not really addressing the objective.
As others have pointed out, you are venturing into unexplored territory and I would have someone awake and standing by to assure all is going well.
Good luck with your experiment.

[Netskier]

I'll have to check leak rate numbers, but am pretty able to notice when it is leaking somewhere.

Yes, I'm blocking the vent ports and anti-asphyxia valve but leave an open nasal port open. This reduces the high flow rate through the mask but still leaves a small flow rate/anti asphyxia port to build up CO2 concentration.

That leads to my next question: is there an XPAP machine that hooks an O2 sat sensor into the machine and records it on the data card with the rest of the data ? That is what I really need to make sure I'm not reaching dangerous CO2 levels.

Thanks for any info.

An oxygen sensor will not measure carbon dioxide. There exist sensors that will sense both gases, but they cost more. I have not yet learned about them.

In general, bilevel machines are more capable than xpap machines, so the better ones probably can handle gas partial pressure sensors. Sleepyhead has some support for oximetry, but I have not tried it yet because I don't have an O2 sensor yet, and a Doctor friend told me informally recently to go all the way and get a sensor to measure both gases because it would teach me so much more. But if Sleepyhead does not support CO2 measurements, then I still would not be able to learn my CO2 levels. I am convinced that measuring gas partial pressures will be the way to go in the near future, and perhaps now.

Does anyone know if Rescan can handle CO2 sensors, and whether Jedimark plans to add CO2 support to Sleepyhead?

[Ltmedic66]

I'll have to check leak rate numbers, but am pretty able to notice when it is leaking somewhere.

Yes, I'm blocking the vent ports and anti-asphyxia valve but leave an open nasal port open. This reduces the high flow rate through the mask but still leaves a small flow rate/anti asphyxia port to build up CO2 concentration.

That leads to my next question: is there an XPAP machine that hooks an O2 sat sensor into the machine and records it on the data card with the rest of the data ? That is what I really need to make sure I'm not reaching dangerous CO2 levels.

Thanks for any info.

An oxygen sensor will not measure carbon dioxide. There exist sensors that will sense both gases, but they cost more. I have not yet learned about them.

In general, bilevel machines are more capable than xpap machines, so the better ones probably can handle gas partial pressure sensors. Sleepyhead has some support for oximetry, but I have not tried it yet because I don't have an O2 sensor yet, and a Doctor friend told me informally recently to go all the way and get a sensor to measure both gases because it would teach me so much more. But if Sleepyhead does not support CO2 measurements, then I still would not be able to learn my CO2 levels. I am convinced that measuring gas partial pressures will be the way to go in the near future, and perhaps now.

Does anyone know if Rescan can handle CO2 sensors, and whether Jedimark plans to add CO2 support to Sleepyhead?

Blood oxygenation can be measured through the finger probe (pulse oximetry). CO2 is measured through exhaled air (capnography), which is what we wear the nasal cannula for during the sleep study. I am not aware of any kind of finger probe to measure CO2.

[jdireton]

I can only say that while I "hear" a whistle while on CPAP, I have asked my wife multiple times what she hears. Without exception, she asks me "What whistle?" I have to wonder if the noise is coming through the machine or through the hose.

Don't know, just commenting.

[stcrim]

There is a real simple and safe solution here. Just apply a regular strength TheraVent. It slows the exhale and thus increases the Co2 level naturally. If it's not enough use the extra strength.

I modify the TheraVent by closing the center vent with tape and then with a leather punch making a new vent (2MM) in the center of each nostril.

[Weird Tolkienish Figure]

Went to my dr. appt. He was justifiably horrified initially that I was changing my pressure settings without him, and then in amazement that I was also closing off some of the mask vents, but when he saw the results, he listened to me and agreed to do an overnight portable oximetry to make sure I was getting enough O2. I think he knew I wasn't going to comply with his normal instructions.

Correct me if I'm wrong but you blocked the antiasphyxiation valve, that would only be "monitored" (ie by you dying) if the power went out right? Find it hard to believe your Doctor has hunky dory about that.

If something exists called an "antiasphyxiation valve" I ain't blocking it off, personally.