Respironics M series overcounting HI ?

[feeling_better]

I have been studying my daily detailed data for only about 10 days worth so far. I have heard of Resmed over counting HI in this forum. I have a suspicion that Respironics M series may be over counting too. Here is why:

Context: Running at about 6.5cm fixed. Had AHI of 28 before treatment, now AI of about 1-2, and HI of about 5-9.

Whenever there is a small short team leak, an H seems to follow very closely thereafter; there are also Hs when there was no preceding leaks. But about >80% of leaks produce an H. Whatever changes happens right after the leak possibly is erroneously detected as H. It could be the flow reduction followed by the plugging of a leak...

On the other hand, it may indeed be physiological. The leak/noise may be causing arousal and one may be slowing/stopping breathing while attending to fix the leak. Even in this case, I would argue that this is a false count, since it is really as a result of an external event caused by the treatment itself. My leaks as very very small and short term; I am extremely sensitive to noise of the leak (of any kind for that matter, while sleeping) so I seem to fix it quickly. The optilife cushions with gel, gives a very good seal at my pressure setting.

BTW, my doc asked me to increase my humidity setting, and I am trying that now; not enough data to make any correlations on that yet. His line of thinking: If the nose is drying out my nasal passeges, there is an increased tendency to do open the mouth and possibly do mouth breathing, and could result in As or Hs. Generally I almost never do mouth breathing.

I am very interested in hearing opinions of the experts here on my speculation of over counting of HI by M series.

[6PtStar]

On the other hand, it may indeed be physiological. The leak/noise may be causing arousal and one may be slowing/stopping breathing while attending to fix the leak.

I don't get a lot of hypotneas but I don't have much of a leak problem with the NAII. I will agree with you on counting them when you have an arousal. Some time when I get up in the middle of the night and can't go back to sleep for a while (just lay there staring at the walls) I do see it counting H's while I am awake. When I asked about this some time back Jim (Goofproof) told me the data is only valid if you are asleep.

Jerry

[Goofproof]

So true, and if your into counting hypotneas, buy a resmed, garenteed to have more for you to count, however if your into counting snores stick with what you have they are great for that.

What matters, is your software AHI, How long and how many apnea events happened, and how you feel, that's what counts. Jim

[dsm]

[quote="feeling_better"]I have been studying my daily detailed data for only about 10 days worth so far. I have heard of Resmed over counting HI in this forum. I have a suspicion that Respironics M series may be over counting too. Here is why:

Context: Running at about 6.5cm fixed. Had AHI of 28 before treatment, now AI of about 1-2, and HI of about 5-9.

Whenever there is a small short team leak, an H seems to follow very closely thereafter; there are also Hs when there was no preceding leaks. But about >80% of leaks produce an H. Whatever changes happens right after the leak possibly is erroneously detected as H. It could be the flow reduction followed by the plugging of a leak...

On the other hand, it may indeed be physiological. The leak/noise may be causing arousal and one may be slowing/stopping breathing while attending to fix the leak. Even in this case, I would argue that this is a false count, since it is really as a result of an external event caused by the treatment itself. My leaks as very very small and short term; I am extremely sensitive to noise of the leak (of any kind for that matter, while sleeping) so I seem to fix it quickly. The optilife cushions with gel, gives a very good seal at my pressure setting.

BTW, my doc asked me to increase my humidity setting, and I am trying that now; not enough data to make any correlations on that yet. His line of thinking: If the nose is drying out my nasal passeges, there is an increased tendency to do open the mouth and possibly do mouth breathing, and could result in As or Hs. Generally I almost never do mouth breathing.

I am very interested in hearing opinions of the experts here on my speculation of over counting of HI by M series.

[-SWS]

I have been studying my daily detailed data for only about 10 days worth so far. I have heard of Resmed over counting HI in this forum. I have a suspicion that Respironics M series may be over counting too. Here is why:

I think the Resmed and Respironics machines have different hypopnea scoring criteria. Supposedly, on that basis alone, the Resmed machines score some hypopneas (by design) that the Respironics machine does not.

Also, the Resmed machine will selectively allow some hypopneas to go untreated that Respironics elects to treats. So that accounts for some of the descrepancy as well.

Regardless I think both machines can occasionally score hypopnea false positives for a variety of reasons.

It could be the flow reduction followed by the plugging of a leak...

I also suspect that scenario sometimes results in hypopnea false positives.

On the other hand, it may indeed be physiological. The leak/noise may be causing arousal and one may be slowing/stopping breathing while attending to fix the leak. Even in this case, I would argue that this is a false count, since it is really as a result of an external event caused by the treatment itself. My leaks as very very small and short term; I am extremely sensitive to noise of the leak (of any kind for that matter, while sleeping) so I seem to fix it quickly.

That sounds possible to me as well. Also, a hypopnea can conceivably be an arousal response to the sensory stimuli of the leak (even without having to fix the leak---in which case it really is a hypopnea).

BTW, my doc asked me to increase my humidity setting, and I am trying that now; not enough data to make any correlations on that yet. His line of thinking: If the nose is drying out my nasal passeges, there is an increased tendency to do open the mouth and possibly do mouth breathing, and could result in As or Hs. Generally I almost never do mouth breathing.

I agree that mouth breathing can cause hypopneas by virtue of therapeutic pressure loss through the mouth: 1) loss of stent, and 2) yet more sensory stimuli that can cause a hypopnea as an arousal-related response.

So there are plenty of plausible scenarios kicking around relative to leaks. Some are false positives and some are genuine hypopneas IMO.