Central Detection Driving Me Nuts!!

[SarcasticDave94]

I have rarely, if ever, noticed the pulses mentioned. I'm awakening on occasion, but every time I'm aware of is due to being up for bathroom and/or the need to get out of bed to stretch the back. This normally happens at 5 AM, and is typical over the past month. AHI at 1.1 for the last 30 days on an ASV machine.

[Reznik]

I have rarely, if ever, noticed the pulses mentioned. I'm awakening on occasion, but every time I'm aware of is due to being up for bathroom and/or the need to get out of bed to stretch the back. This normally happens at 5 AM, and is typical over the past month. AHI at 1.1 for the last 30 days on an ASV machine.

Hi Dave,

Thanks for responding.

ASV machines don't send the FOT pulses of 1cm at 4hz.  It just increases the pressure until you breath.

[kiwii]

Thank you to everyone who responded to far.  I'm going to respond to each of you, below:

...Resmed uses the Forced Oscillation Technique, which blows a 4hz pulse of 1cm air at you starting four seconds after any apnea and continuing until you start breathing again.

Is this true? I'm using the ResMed AirCurve 10 VAuto, and have woken up to find that I am not inhaling. The machine is doing nothing, as far as I can tell. There is certainly no increase in pressure until I start breathing again. This is why my doctor(s) are recommending a machine that has a backup rate for me.

What you have written is what I expected from my machine -- some way to 'make' me breath if I had stopped. Mine does not do that.

The FOT pulses are NOT enough to stimulate a breath.  If you want a machine that's going to force you to breath when you stop breathing, you need a machine with a timed backup (AirCurve 10 ST) or an ASV model (AirCurve 10 ASV).  Both are VERY expenses.

Right. When I was lying there, trying to initiate an inhale (and not succeeding) I did take note that I could not feel anything from the device, at least as best as I can recall it now. I do remember being surprised, since there have been times that I'm very aware of the air being delivered.

So when you mentioned these pulses, it made me wonder. Surely I would have felt them.. ?

edit: Btw, I was on my back, and I do not use ramp... and before anyone mentions sleep paralysis - I was able to easily turn onto my side to resolve the problem. If there is sleep paralysis, it only affects my diaphragm (I'm guessing) since that is what was not responding to my efforts.

[SarcasticDave94]

Reznik,

FWIW: when on either CPAP or BiPAP, I woke more tired than rested constantly. Dangerously so even. Yes, I'm aware this was predominantly due to central apneas caused and/or initiated by the other devices. Hence the reason I'm on an ASV. It is definitely required for my proper treatment.

Regardless of that, any patient that cannot benefit by their apnea device should be able to gain better support by adjusting their device to optimal settings.

I'm guessing my thoughts are along the lines of these two questions. Is your machine settings optimized? And are you assured you're on the right machine? And I'm referring to more than the FOT capable vs not.

[Madcat207]

Bumping a slightly old thread, but because i feel like it suddenly applies to me.

This weekend i was not sleeping well (stress, ironically again over my health, and specifically my heart), and noticed something odd when i was roused (especially this morning). I wish i knew how to describe it, but immediately on waking, i swear i felt three... "thumps". As i laid there, i didn't notice any more, and i could basically feel my heart (i have been keenly aware of my pulse, and can feel it in my body if i am calm or concentrate) and it felt steady (didn't feel like it was racing). Interestingly enough, i remember this happened the night before as well, thought the rest of that morning sleep was just badly disturbed. I thought it might be gas, but i didn't burp, and i didn't feel any other disturbances..

Part of my over-worry with my health was that my heart rate was able to get into the 50s at night (even very high 40s every so often), and that it was a bad thing (no reason other than panic on that one though); or that maybe i was having another problem. But thinking about it, given that i remember 3 distinct feelings, but then totally normal (which a heart would not do), i can only conclude that for some reason, i felt the pulses (as it was, this morning happened only a few minutes before my alarm). Sure enough, there was a CA noted at what i would expect was that time as well, so it would make sense the machine pulsed..

For those sensitive.. do you actually feel the pulses, or is it just.. waking you up?

[Sleeprider]

Many members have felt the pressure pulses from the machines. They don't mean much as there may be a transitional central upon arousal. Your graph should show whether you received a FOT pulse.

[Reznik]

Reznik,

FWIW: when on either CPAP or BiPAP, I woke more tired than rested constantly. Dangerously so even. Yes, I'm aware this was predominantly due to central apneas caused and/or initiated by the other devices. Hence the reason I'm on an ASV. It is definitely required for my proper treatment.

Regardless of that, any patient that cannot benefit by their apnea device should be able to gain better support by adjusting their device to optimal settings.

I'm guessing my thoughts are along the lines of these two questions. Is your machine settings optimized? And are you assured you're on the right machine? And I'm referring to more than the FOT capable vs not.

Because it is designed to treat both central and obstructive apneas, The ASV machine does not deliver pressure pulses.  

What if the centrals weren't the cause of your issues, but the pressure pulses were?  You may have done just as well, if not better on a CPAP machine costing 1/8 of the price that did not deliver those pulses.

[Reznik]

Many members have felt the pressure pulses from the machines.  They don't mean much as there may be a transitional central upon arousal.  Your graph should show whether you received a FOT pulse.

I've now been using CPAP (with the pressure pulses turned off) for about nine months.  I continue to have centrals, but I sleep fine, wake feeling rested, and my O2 never drops below 90.  

My sleep can be disrupted by something as simple as my wife tapping me on the shoulder.  My nose being wiggled by the FOT pulses on the CPAP definitely disrupted my sleep.  

Interestingly, the AHI actually goes DOWN when I turned the FOT pulses on, but I wake up feeling awful.  Presumably, the machine waking me up every time that I have an apnea or a hypopnea reduces the number, but the trade-off is poor sleep.

It is no wonder, to me at least, that the compliance rate for new CPAP users is less than 50%.  I suspect that the central apnea detection that is pervasive in almost all of the Resmed machines and which cannot be turned it is a significant culprit.  

Notably, the sleep lab machines DO NOT send these pulses, and thus the patient's ability to tolerate FOT pulses is not tested when the patient is hooked up to the very equipment that would let the doctor know whether these pulses are disrupting the person's sleep or not.

[SarcasticDave94]

Hi Reznik,

It sounds like you have been able to resolve the FOT causing disruptions. Has CPAP therapy been more successful since you found a way around FOT being a problem?

As this thread has developed over time, my understanding of my own therapy has grown, and I now see my lack of understanding was quite evident in my earlier posts here. I was, and still am, quite aware of why I was transitioned onto an ASV however. The overnight sleep study I took which was used as the transition from CPAP to BPAP clearly indicated 124 Centrals (one 90 seconds in duration) vs 24 Obstructive. I would have had to take BPAP therapy as the next required step for insurance purposes to get the ASV most likely anyway. I did fail BPAP almost immediately, as it was proven to increase central events, and causing greatly increased fatigue for which the centrals may have contributed.

Note this doesn't address your FOT issue, I am attempting to make clear that my developing understanding of apnea treatment in general has gotten a little bit better. At the time of those prior posts, I was not aware that FOT did not apply to my AirCurve 10 ASV, so I offer a sincere apology for inclusion of my device in the discussion.

If you do not mind my asking, what exactly did you need to do in order to get past the FOT issue? It may help others that are having difficulty with FOT to know of a solution that could be considered.

[Reznik]

Hi Dave,

I was never able to tolerate the FOT pulses.  

I resolved the issue by buying one of the few Resmed machines that allow you to switch them off, at my own expense.