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Following that solenoid-valve theory a bit... Perhaps the Trilogy firmware doesn't bother with solenoid-valve purges in AVAPS mode---but occasionally purges in AVAPS-AE mode. Additionally the bed-shifts might present the machine with pressure characteristics matching algorithmic criteria for a purge.

If the graph below depicts a purge conducted by firmware, then the beginning-to-end process appears to take around 45 seconds. Madalot, do all the pulsations in your graphs happen to take around 45 seconds?

I noticed that your directview software is version 1.3. Maybe you need updated software to view the Avaps-AE waveforms correctly. I bought my directview about 6 months ago and it's version 2.2.

-SWS wrote:

Following that solenoid-valve theory a bit... Perhaps the Trilogy firmware doesn't bother with solenoid-valve purges in AVAPS mode---but occasionally purges in AVAPS-AE mode. Additionally the bed-shifts might present the machine with pressure characteristics matching algorithmic criteria for a purge.

If the graph below depicts a purge conducted by firmware, then the beginning-to-end process appears to take around 45 seconds. Madalot, do all the pulsations in your graphs happen to take around 45 seconds?

I have NOT had a chance to upload last night's data. And when my desktop hard drive crashes for good, I won't be able to scan the reports until later in the week after I get a new hard drive and reinstall all my programs. I will attempt to upload the data on my netbook later this afternoon and look at last night's data, specifically around 5:25 (or 5:22 or so) when I woke to these pulses. Assuming I CAN get it uploaded AND scanned before my drive crashes, I will post it tonight.

The length of time these pulses last varies from a few seconds, to maybe 20-25 seconds. I do NOT believe any of them have lasted as long as 45 seconds.

The equipment listed in my signature IS accurate. The mask is being used as it comes out of the box with nothing but an antibacterial filter added between the Trilogy & the hose.

boots wrote:I noticed that your directview software is version 1.3. Maybe you need updated software to view the Avaps-AE waveforms correctly. I bought my directview about 6 months ago and it's version 2.2.

Where did you buy it and how much did it cost?

Where did you buy it and how much did it cost?

$181
http://www.oxymaster.net/ProductDetail/ ... fault.aspx

Madalot wrote: The length of time these pulses last varies from a few seconds, to maybe 20-25 seconds. I do NOT believe any of them have lasted as long as 45 seconds.

Okay. The train of pulsations in your above chart commence around the 08:13:05 point and complete around 08:13:50, give or take. I certainly wouldn't rule out guest's solenoid-purge theory based on variable length, however. Uniform length might have bolstered that theory---since respiratory events and treatment are more associated with variability.

My computer has given me a reprieve and DirectView is working again AND found my data. So, I uploaded everything from last night.

At the time I know it was pulsing, I found it on the waveform. No doubt about it and there were several of them during a 45-minute timeframe. Some I know I moved, some I was absolutely still when the pulsing started.

The Daily Detail for last night looks good, but the PTB is still down (92.12) from my norm. Tidal Volume was great, averaging 473.97. EPAP Average was 9.56.

I still do not know WHEN the downward trend on PTB began but know it has been the entire time I've had this Trilogy. The switching to AVAPS-AE has actually stabilized it where it hasn't gone below 90%, where as on regular AVAPS, it was all over the map, dipping down as low as 80% on a couple nights.

We're also discussing switching to Auto Trak. As ~SWS has suggested, I think ONE change/modification at a time is appropriate. Aside from the pulsing, the max EPAP of 10 is NOT bothering me and the data looks pretty good.

Assuming I am going to continue on this, should I go to Auto Trak next to see if that helps with the pulsing or should I go ahead and bump up the max EPAP next?

If anyone wants to see reports/waveforms before giving an opinion, tell me what to upload and I will try to do it (as long as my computer behaves).

Madalot wrote: If anyone wants to see reports/waveforms before giving an opinion, tell me what to upload and I will try to do it (as long as my computer behaves).

Leak is one of Direct View's available data channels. How about adding the Leak line so we can see if leaks precipitate those pulsations on your flow graph?

To accomplish a graph like that, temporarily "add" only the Flow and Leak data channels on the Waveforms page---temporarily "remove" the rest.

Also make sure your circuit type on the Direct View configuration page reflects a "passive" circuit rather than "active"...

-SWS wrote:

Madalot wrote: If anyone wants to see reports/waveforms before giving an opinion, tell me what to upload and I will try to do it (as long as my computer behaves).

Leak is one of Direct View's available data channels. How about adding the Leak line so we can see if leaks precipitate those pulsations on your flow graph?

To accomplish a graph like that, temporarily "add" only the Flow and Leak data channels on the Waveforms page---temporarily "remove" the rest.

No problem. Give me an idea of the amount of time you want and how detailed - ie how spread out.

-SWS wrote:Also make sure your circuit type on the Direct View configuration page reflects a "passive" circuit rather than "active"...

CONFIRMED: Both Primary & Secondary Configuration indicates "passive" --

Madalot wrote: No problem. Give me an idea of the amount of time you want and how detailed - ie how spread out.

I'm trying to reject my own hypothesis that transient leaks somehow precipitate those annoying pulsations. So try to find one or two examples where leaks are well-behaved immediately before and during the flow pulsations.

If you can, please zoom in and display the Flow and Leak graphs with the same scale you used below:

Here you go. I've never looked at the data like this before. Intriguing.

We posted at the same time. The ones I used were a little more detailed. Do you want me to do it again, backed out a little bit?

That resolution looks great. Can you post another comparison graph when there are no pulsations---same resolution, same pair of waveform channels?

-SWS wrote:That resolution looks great. Can you post another comparison graph when there are no pulsations---same resolution, same pair of waveform channels?

Yes, but don't wait on me right now. Hubby has come home and is taking me out for a bite to eat. I'll do it and post it when I get back. An hour or more probably.

Later today or even another day is fine... Enjoy your outing!

I drew some vertical lines beginning where the pulsations commence on the leak graph----straight up to where the pulsations commence on the flow graph. The pair of pulsations appear to start and end together. There are a couple instances where the pulsations begin on the leak graph briefly before they begin on the flow graph. I'm not yet ready to reject the hypothesis that transient mask leaks factor in...

A solenoid purge is a leak--that would reflect on the leak line. So I'm not yet ready to reject guest's solenoid-purge hypothesis either. Boots suggested Direct View display nuances between versions might explain the pulsations as graphing error. However, if Madalot feels the pulsations, then they are more than a graphing bug...