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04-04-2019, 06:24 PM (This post was last modified: 04-04-2019, 06:42 PM by Reznik.)
RE: Apneas or Cheyne-Stokes Respirations?
Okay, I've omitted Flow Limit because the mode that I'm using doesn't detect flow limitations (the chart is empty) and Pressure (because I'm on a fixed pressure). I also omitted snore because it didn't show anything.
I have FOT off (it wakes me up) and so the events are all yellow (indicating that the device cannot tell if they are obstructive or central).
The chart reveals that I woke up between 4:30 to 5:00 a.m. and did not get back to sleep for 20-30 minutes. That's typical. Sometimes, I don't get back to sleep at all. There are two other instances where I woke up and turned the machine off, went to the bathroom (probably unnecessarily, but it's what I do), and then went back to sleep (at 6:30 a.m. ish and 7:30 a.m. ish), which is also typical.
Knowledge of all events as to if they are central or obstructive is important for determining therapy since with tour machines the treatments are basically the opposite of each other.
Lower your pressure to the minimum you can stand assuming that the vast majority of the events are central.
Gideon - Project Manager and Lead Tester for OSCAR - Open Source CPAP Analysis Reporter
04-04-2019, 09:22 PM (This post was last modified: 04-04-2019, 09:27 PM by Reznik.)
RE: Apneas or Cheyne-Stokes Respirations?
Unfortunately, the FOT pulses used by ResMed disturb my sleep. When FOTs are on, the number of apneas that I experience drop dramatically (<3), but I feel terrible the next morning. This is a case where measuring something affects the thing that's being measured.
I know that F&P have a new model that detects central/obstructive apneas passively, by analyzing the breathing waveforms. I hope that ResMed chooses to go in that direction in future models. Given the massive database that ResMed is compiling using the cellular modems in our devices, I would think that ResMed would be able to come up with a reliable algorithm for doing so.
In the meantime, I think that you're advice is good. I'll see what happens with the lower pressures.
Thank you very much for taking a look and offering your advice. Let me know if you think of anything else.
(04-04-2019, 09:44 PM)bonjour Wrote: Other than manually evaluating the entire night to classify, which is what they do at sleep labs, I don't know.
Well, virtually all of my apneas look just like the waveform that I started this thread with, and so if you're right about them being central, then we've already done the work of classifying the rest.
If your events show the wave form you showed at the start that I described as periodic breathing that is central based. If your ahi does not reduce with a reduction in pressure support then only fix would be an ASV Machine I recommend Resmed but the pressure changes may wake you. If you can get a used machine or a means of trial.
Did you have centrals recorded in your sleep test ? What is your current nightly AHI
(04-05-2019, 12:57 AM)jaswilliams Wrote: If your events show the wave form you showed at the start that I described as periodic breathing that is central based. If your ahi does not reduce with a reduction in pressure support then only fix would be an ASV Machine I recommend Resmed but the pressure changes may wake you. If you can get a used machine or a means of trial.
Did you have centrals recorded in your sleep test ? What is your current nightly AHI
Hi Jaswilliams,
Thank you very much for taking the time to read through everything. I do plan to try eliminating the pressure support and lowering the pressure to see what happens.
I've had two PSGs, but I'm such a terrible sleeper that I got very little actual sleep during either. The first PSG didn't involve CPAP. The second titration did, and there were centrals recorded during my second PSG.
I welcome any additional thoughts or comments.
Is there any definitive guide on how to interpret wave forms to determine whether an apnea is central vs. obstructive?
Definitive is defined as lack of breathing effort as determined with strain gages on chest and belly and brain wave patterns.
In the SleepyHead guide there are many examples of waveforms.
Look for effort in the pause between breaths and obstructive apneas frequently end with a recovery breath where centrals generally do not. Flow limits w clipped tops are obstructive with smooth waveforms could be Central.
Gideon - Project Manager and Lead Tester for OSCAR - Open Source CPAP Analysis Reporter
