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archangle wrote:

igdoc wrote:Could be a blockage of the flow sensor.

Look at the leak rate. It stays pretty much the same throughout the event. That strongly suggests:

The flow rate sensor is not plugged and is functioning normally.
The average pressure in the mask was the same before and during the event.
The hose is not plugged or kinked, unless it's plugged or kinked between the exhaust port and your lungs.
There's not some sort of leak event causing the problem.
The exhaust vent isn't blocked.

could you please explain your logic? you start out saying that the *flow* sensor can't be clogged and then cite examples from the chart that are from the *pressure* sensor.

I agree, the *pressure* sensor, and the leak rate derived from it, indicate that the vent isn't blocked, there's no kink in the hose. mask *pressure* spikes with the ASV pulses. but there's no concomitant *FLOW* recorded from the *flow* sensor.

your soapboxing about what resmed does notwithstanding, the flow sensor doesn't sense pressure, so what's all the pressure readings have to do with it?

igdoc wrote:Archangle, excellent point about the constant leak rates putting any mechanical blockage beyond the vent ports. Not familiar with the Pilairo but I wonder if the pillows could displace and impact into the skin. It is pretty extreme and sudden for nasal blockage. Thank goodness for mouth breathing!
Ian

Ian,

If I were mouth breathing, would'nt it show up on the leak data........... hmmmmm, so if both pillows were blocked almost completly from being nasal clog or on skin then it would not show any leak data except the normal leak line that the pilairo has...

Very interesting, I would have had to breath through my mouth and not even notice it and then stop instantly the minute my mask became unclogged?? if the mask was on skin and not providing any air through my nose, when it started providing air, would that have shown a massive leak for atleast a few seconds?

I will take some more screenshots when I get home tonight, It will be late as I probably wont get off until 2000...

Cowboy Casey wrote:If I were mouth breathing, would'nt it show up on the leak data........... hmmmmm, so if both pillows were blocked almost completly from being nasal clog or on skin then it would not show any leak data except the normal leak line that the pilairo has...

Very interesting, I would have had to breath through my mouth and not even notice it and then stop instantly the minute my mask became unclogged?? if the mask was on skin and not providing any air through my nose, when it started providing air, would that have shown a massive leak for atleast a few seconds?

Casey,
You have answered the first question correctly, if the pillows were completely blocked there would be no additional mouth leaking. 'Normal' mouth breathing would probably not wake you up. Very good point about a large mouth leak when the mask unblocked and you might look closer for a spike in the data but I certainly cannot see it in the graph. The alternative is that the pillows had shifted sufficiently to also unblock your nose and that you continued to nose breath to a reasonable level despite the mask blockage. As you can tell we are all guessing a bit here. Interesting!
Ian

archangle wrote:

Sludge wrote:I like the "occluded pillows/nasal passages" argument.

Sludge, do you think the reported tidal volume/minute vent numbers are below the possible levels? i.e. would he be dead if all the data was really correct? Can we assume that there's either a data glitch or he's somehow breathing "around" the mask? His tidal volume appears to be below 170 for quite some time and minute vent is around 1 for a while?

Right, "IMHO" I think that thing is simply pounding against a total occlusion.

Some clues may be seen during the reappearance of the flow waveform.

Sludge wrote:

archangle wrote:

Sludge wrote:I like the "occluded pillows/nasal passages" argument.

Sludge, do you think the reported tidal volume/minute vent numbers are below the possible levels? i.e. would he be dead if all the data was really correct? Can we assume that there's either a data glitch or he's somehow breathing "around" the mask? His tidal volume appears to be below 170 for quite some time and minute vent is around 1 for a while?

Right, "IMHO" I think that thing is simply pounding against a total occlusion.

Some clues may be seen during the reappearance of the flow waveform.

Do you mean that there's not enough air to keep him alive? The airflow the machine is seeing is just the pressure compressing air, inflating the hose like a balloon, etc., not actually going into his lungs? That sort of makes sense.

Ok everyone, Here are some screenshots of 3 minutes before and 2 minutes after this happened.. Also the encore report of the night..

Of course everything went wrong tonight... My mouse died, the keyboard died, and my monitor on my laptop is gone..... Gotta love this crap.... took 2 different computers to get this done..

Screenshot 2014-08-21 21.09.30 by cowboycasey, on Flickr

Screenshot 2014-08-21 21.09.07 by cowboycasey, on Flickr

Screenshot 2014-08-21 21.09.22 by cowboycasey, on Flickr

Screenshot 2014-08-21 21.05.51 by cowboycasey, on Flickr

Screenshot 2014-08-21 21.05.32 by cowboycasey, on Flickr

Cowboy Casey wrote:Ok everyone, Here are some screenshots of 3 minutes before and 2 minutes after this happened.. Also the encore report of the night..

That's all at the end. How about the beginning? Good to see that Encore shows the same thing as SH.

palerider wrote:

archangle wrote:

igdoc wrote:Could be a blockage of the flow sensor.

Look at the leak rate. It stays pretty much the same throughout the event. That strongly suggests:

The flow rate sensor is not plugged and is functioning normally.
The average pressure in the mask was the same before and during the event.
The hose is not plugged or kinked, unless it's plugged or kinked between the exhaust port and your lungs.
There's not some sort of leak event causing the problem.
The exhaust vent isn't blocked.

could you please explain your logic? you start out saying that the *flow* sensor can't be clogged and then cite examples from the chart that are from the *pressure* sensor.

I agree, the *pressure* sensor, and the leak rate derived from it, indicate that the vent isn't blocked, there's no kink in the hose. mask *pressure* spikes with the ASV pulses. but there's no concomitant *FLOW* recorded from the *flow* sensor.

your soapboxing about what resmed does notwithstanding, the flow sensor doesn't sense pressure, so what's all the pressure readings have to do with it?

It's not 100% proof, just reasonable assumptions, but here's the idea. I can expound if necessary.

Short version - The constant value of the leak rate strongly suggests the machine is correctly measuring the raw flow rate. The constant leak rate suggests the pressure at the elbow is constant. The constant pressure at the elbow suggests the machine is correctly sensing the pressure.

Medium version.

The respiratory flow rate graphs, minute vent, tidal volume drop by a factor of 4:1 or sor.
The leak rate doesn't change very much.
The leak rate graph peaks and dips roughly in proportion to the EPAP graph.
- The leak rate display is correct.
- Since the leak rate doesn't jump, there's not a big leak somewhere causing the event.
The leak rate is calculated as a time average of the hose air flow rate.
- The machine's hose flow rate calculation is correct.
The leak rate doesn't spike a lot like mask or mouth leaks tend to do. No sudden jumps
- The leak rate is mostly the leak through the exhaust vent.
- Since the exhaust vent rate is constant, the airflow is not blocked between the elbow and the blower.
- The exhaust vent isn't blocked.
The exhaust vent leak rate is proportional to mask pressure at the elbow where the vent is located.
-The average mask pressure is constant. (Constant as in not varying 4:1 during the event.)
-The machine's pressure regulation is working correctly.
-The pressure readings are correct.

hmm. good points... probably not a partially blocked flow sensor then.

oh well, back to my original theory... pugsy's aliens abducted him, probed him thoroughly, and found out he uses flickr to post his screenshots, and tossed him back.

I believe the graph supports the "Mask has shifted and eyeballs are being ventilated while CC is off breathing on his own" theory.

There are adjustment breaths as the interface is is reestablished:



The I:Time is a little screwy, but since "stable" registers at -0-, that may be an issue with SH.

There may/must have been a few areas where there were leak surges, but they may have been absorbed by Signal Averaging.

archangle wrote:... or your nose is mostly clogged or blocked.

I don't believe that to be the case, as a view of CC's beak (although somewhat from a distance) shows that thing to be of pretty fair size, so an occlusion would most certainly seem to be memorable, if not totally disruptive to sleep.

Ok, so not a fluke, it happened again last night... This time I was ready and changed some settings on my ASV so the pressure support would max out and also wake me up once it got so high my mask would start leaking... That is exactly what happened, it raised the pressure support to 20, kept me breathing and woke me up once it started leaking... It really freaked me out cause I was out of it and couldn't figure out what was going on, I tried to wake up and look at what the pressure was but hit the ramp on accident... I have given the last report to the VA doctors and in the last week only a nurse has looked at it... Not sure where to go with this, a sleep doctor I believe will not have any clue what to do with this....

next time, don't fiddle with it, just start breathing, and see if it responds and goes back to normal, or if it keeps not sensing your breaths.

I don't know what data shows on the lcd while it's operating, but try and wake up enough, if it doesn't return to normal, to check the data, if there is any...

Most likely seems to be that the mask is blocked off completely after the exhale vent. Either collapsed somehow or shifted on your face and isn't blowing into your nose. Or somehow, your nose has completely blocked off. The nearly constant leak rate suggests the air path is open all the way up to the exhale vent. The idea is you're breathing at that time, but not through the mask.

Did you wake up right after this event? How did you feel? How did you feel in the morning?