Sandman Auto

[roster]

..... But man I had a rough night last night, woke up couldn't breathe, felt like I had a golf ball in my throat way down LOW like in the adams apple, guess I had a vocal cord closure, I really panicked I could not breathe then it popped open and I gasp for air, by then I was sitting up with the mask off. Freaky deal, never had one of those before and hope I never have another.

Sorry to hear that. Any indication from your software of how long the closure was?

[Thunder Road]

Hang in there Snoredog-we need your knowledge and inspiration. Many of us just choose to witness you and others (Wulfman,Rested Gal among many others) and the brilliance all of you bring to the forum. To all of our bilevel users I hear that Covidien is close to introducing the Sandman Duo and Sandman Duo ST. Keep hosing fellow hosers because "baby we were born to run"

[echo]

Wow Snoredog, sorry to hear it. Never heard of vocal cord closure but it sure does sound freaky! Hope it doesn't come back...

[-SWS]

woke up couldn't breathe, felt like I had a golf ball in my throat way down LOW like in the adams apple, guess I had a vocal cord closure, I really panicked I could not breathe then it popped open

Snoredog, I'm sorry to hear about that as well. Could be a vocal cord closure. And GERD can trigger that. However, when GERD beats up the esophagus, the esophagus can get pretty swollen. That swollen esophagus in turn can apply physical pressure to the adams apple.

If you haven't been scoped out in a while it might be a good idea to let the docs have a "look see". If there's GERD related damage you just may have to modify your treatment regiment and/or lifestyle a bit... Please take care, my friend!

[ozij]

The present invention also provides a method for resolving an ambiguity in breath monitoring to determine whether or not breathing is labored due to an obstruction, by the presence or absence of cardiogenic oscillations. According to the present invention, identification of inspiratory flow limitation can be accomplished with improved accuracy even when the breaths show a shape which is intermediate between definitely abnormal shape (flow limited) and definitely normal sinusoidal shape. This is accomplished by further examining whether there is cardiogenic oscillation present during expiratory periods and between breaths. This is detected by signal processing to enhance and identify small oscillations in the flow signal in the range of the pulse frequency in the range of the pulse, which oscillations represent cardiogenic oscillations. When these oscillations are detected, and breath whose shape is possibly abnormal, i.e., ambiguous, the breath may be classified as normal. When oscillation is absent, the threshold of the parameters used to classify the the shape of the inspiratory airflow abnormal is lowered and the breath is classified as having a high resistance. This technique is used to make the decision as to whether therapeutic CPAP pressure needs to be raised for obstructive events. It has the benefit of avoiding false positive detection of abnormally shaped breaths causing excessive rise in pressure in those patients who have them, while not sacrificing sensitivity to abnormal events in those who are more classical. The inspiratory flow signal, both amplitude and contour, and the presence or absence of cardiogenic oscillations on the flow signal are used to define the state of resistance of the upper airway.

So cardiac oscillations are definitely used to differentiate central from obstructive apneas. But cardiac oscillations are also used to help differentiate central hypopneas from obstructive hypopneas---specifically when flattening or "obstruction-hinting" wave shape of the hypopnea's flow signal is ambiguous (i.e. the flow signal is not quite sinusoidal or perfect, but not properly FL shaped either). That's when cardiac oscillations enter the hypopnea differentiation routine.

I wonder if the part of the algorithm I marked in red is the reason some of us need to turn off the response to flow limitation runs.
Rapoport's cardiogenic oscillation data shows that some people have them for all central events, others for none.
If there are less cardiogenic oscillations in some people's ambiguous breaths, you'd expect the machine to be trigger happy in identifying those breaths as flow limited, and to get too many false positive flow limitation runs.
O.

[Snoozing Gonzo]

I can't say how happy I am to see this discussion among the most focused minds on this site. I have been on - and happy enough- on a Remstar CPAP for about three years with an Everest for travel. Over time I found about 9.5 - 10 cmH20 was about right (originally titrated at 8.0) on both machines. After losing some weight I decided it was time for an APAP to get a better idea where things were at.

I now have about 350 hours on a Sandman Auto w/software (card downloads). Most noticible, and pleasant to me, was the way it handles humidification. I haven't plugged in the heated hose since I bought the machine.

After only looking at CPAP readings though Encore Pro, I've been confused by the array of terminology and data I now see. I have set the machine at 8.0 - 11.5. It rarely hits 10 cmH20 on runs and the average each night is around 8.3 with about a 1 AHI but seems to count the centrals separately with 3 - 5 per night. One my questions has been the new arrival of centrals in the data. This thread (and one from a couple months ago) has helped me to understand enough to begin digging.

Thanks again!

Chris

[Snoredog]

I can't say how happy I am to see this discussion among the most focused minds on this site. I have been on - and happy enough- on a Remstar CPAP for about three years with an Everest for travel. Over time I found about 9.5 - 10 cmH20 was about right (originally titrated at 8.0) on both machines. After losing some weight I decided it was time for an APAP to get a better idea where things were at.

I now have about 350 hours on a Sandman Auto w/software (card downloads). Most noticible, and pleasant to me, was the way it handles humidification. I haven't plugged in the heated hose since I bought the machine.

After only looking at CPAP readings though Encore Pro, I've been confused by the array of terminology and data I now see. I have set the machine at 8.0 - 11.5. It rarely hits 10 cmH20 on runs and the average each night is around 8.3 with about a 1 AHI but seems to count the centrals separately with 3 - 5 per night. One my questions has been the new arrival of centrals in the data. This thread (and one from a couple months ago) has helped me to understand enough to begin digging.

Thanks again!

Chris

they have changed the name of a few of the features found on the 420e that I can tell, my AHI has never been high with it either. You might as well include the centrals in your AHI count, the Remstar does but the difference is the Sandman won't increase pressure when those are present where the other machine most likely would.

Keep an eye on them, try and note to note a pressure "pattern", if they show up at random pressures there is not much you can do about them. But for example if they consistently show up at 10 cm pressure, you might experiment with lowering the Command on Apnea setting from 10 to 9 and you may be able to eliminate them. That is the setting I use and it seems to keep mine at bay. I also had to disable Command on Flow Limitation or the IFL1 setting. Your Sandman has a new listed feature setting called Pressure Decrease with fast/slow, 420 doesn't have that, but it has IFL2, don't know if that is the same thing or not.

If you have the software the 96-hour report would be interesting to see, if you have that, after clicking on the tab, click on the right forward button, then the magnifying class to expand it. Should give you pretty good "Details" about the session you clicked on.

While I always liked Cflex on the Remstar, I didn't care much for Aflex, mainly how it left me feeling. I now wonder if a Bipap would not leave me feeling the same. It wasn't a matter of comfort, it was how I was left feeling the next day.

I think when they do these studies they should do them blind without the patient knowing what machine was used, then they would have to go by how they feel albeit subjective.

[Snoredog]

I can't say how happy I am to see this discussion among the most focused minds on this site. I have been on - and happy enough- on a Remstar CPAP for about three years with an Everest for travel. Over time I found about 9.5 - 10 cmH20 was about right (originally titrated at 8.0) on both machines. After losing some weight I decided it was time for an APAP to get a better idea where things were at.

I now have about 350 hours on a Sandman Auto w/software (card downloads). Most noticible, and pleasant to me, was the way it handles humidification. I haven't plugged in the heated hose since I bought the machine.

After only looking at CPAP readings though Encore Pro, I've been confused by the array of terminology and data I now see. I have set the machine at 8.0 - 11.5. It rarely hits 10 cmH20 on runs and the average each night is around 8.3 with about a 1 AHI but seems to count the centrals separately with 3 - 5 per night. One my questions has been the new arrival of centrals in the data. This thread (and one from a couple months ago) has helped me to understand enough to begin digging.

Thanks again!

Chris

they have changed the name of a few of the features found on the 420e that I can tell, my AHI has never been high with it either. You might as well include the centrals in your AHI count, the Remstar does but the difference is the Sandman won't increase pressure when those are present where the other machine most likely would.

Keep an eye on them, try and note to note a pressure "pattern", if they show up at random pressures there is not much you can do about them. But for example if they consistently show up at 10 cm pressure, you might experiment with lowering the Command on Apnea setting from 10 to 9 and you may be able to eliminate them. That is the setting I use and it seems to keep mine at bay. I also had to disable Command on Flow Limitation or the IFL1 setting. Your Sandman has a new listed feature setting called Pressure Decrease with fast/slow, 420 doesn't have that, but it has IFL2, don't know if that is the same thing or not.

If you have the software the 96-hour report would be interesting to see, if you have that, after clicking on the tab, click on the right forward button, then the magnifying class to expand it. Should give you pretty good "Details" about the session you clicked on.

While I always liked Cflex on the Remstar, I didn't care much for Aflex, mainly how it left me feeling. I now wonder if a Bipap would not leave me feeling the same. It wasn't a matter of comfort, it was how I was left feeling the next day.

I think when they do these studies they should do them blind without the patient knowing what machine was used, then they would have to go by how they feel albeit subjective.

[Snoozing Gonzo]

Thanks Snoredog, I will check closer for central patterns and try your suggested adjustment to see what happens. I left the fast/slow switch on its default, fast, for now. I read a discussion you participated in a couple of months agot with SWS, Ozij, and others that included analysis of the IFL1 setting and wondered if the two had similar intent.

Your comment about pressure relief was interesting as I have found that I am generally more comfortable without it. However, it seemed dependent on masks and humidity (using pillows I tended to like low Cflex assistance, my Activa not at all... higher humidity led me to be more comfortable with Cflex than lower). I haven't tried a different mask with the Sandman yet but may dig out an Opus 360 or Optilife to see how it does. Because the Sandman tends to find lower pressures best for most of my nights and I can't seem to go to sleep well under 9 cmH20 my ramp is different than most, I start high (at 9 - 9.5).

Thanks again for your interest and advice

Chris

[-SWS]

I left the fast/slow switch on its default, fast, for now.

Does the clinician's manual or even HELP section of the Sandman Series software happen to say anything about that fast/slow switch?

If it's a "Pressure Decrease with fast/slow" switch, then it's not the same as IFL1 or IFL2---since those are system triggers for pressure increases. It sounds like a feature that allows you to select how fast or slow the machine returns to baseline or prescribed pressure (the initial or starting APAP pressure between min and max).

I wonder if the part of the algorithm I marked in red is the reason some of us need to turn off the response to flow limitation runs.
Rapoport's cardiogenic oscillation data shows that some people have them for all central events, others for none.

Bear in mind that Rapoport's data is for frank central apneas. If Rapoport's algorithm attempts to use cardiogenic/cardiac oscillations as a "tie breaker" for open-airway obstructive events (lesser FL and H with only intermediate shapes), then I would expect an even larger CA discrepancy in epidemiology than with that graph of frank central apneas. Sure could be wrong about that, though... and probably am. This algorithmic problem seems to be an exercise in counterintuition.

Regardless the patent description calls for cardiac oscillation detection to occur during expiratory pause---but only if needed as a tie-breaker. Thus if heart-beat is not detected (along with presence of that intermediate wave shape needing a "tie-break") then the lesser FL event up for differentiation is deemed obstructive and pressure increase is allowed. But holding off on some pressure increases during presence of expiratory-pause heartbeat, in and of itself, shouldn't constitute basis for pressure runaway. The twofold premise of: 1) employing intermediate/indeterminate flow shapes in the first place, and 2) differentiating those indeterminate shapes with a low-specificity technique is perhaps the crux of the problem. So in this scenario we get very high FL sensitivity, with many false-positive patients left in the cold as they suffer from that sacrificed specificity. They would have to turn IFL1 off. So I think your theory fits that hypothetical scenario, ozij. Right now that's my favorite theory going.

Alternately I'm also wondering if the FL (wave shape based) detection on this machine might be sensitive enough to detect an ever-so-slight defensive partial closure----an extremely slight CompSA/CSDB type of reflexive airway response to pressure increases that the other machines can't detect for lack of FL sensitivity. That scenario, if it even existed, should work itself into a bona fide state of FL-based pressure runaway. And central/obstructive differentiation wouldn't help one bit for "ultra-slight" reflexive airway closures. Those patients would have to turn IFL1 off as well for lack of effective temporal-variable pressure analysis in the algorithm. A very distant second-favorite theory for me at the moment.

[StillAnotherGuest]

I left the fast/slow switch on its default, fast, for now.

Does the clinician's manual or even HELP section of the Sandman Series software happen to say anything about that fast/slow switch?

If it's a "Pressure Decrease with fast/slow" switch, then it's not the same as IFL1 or IFL2---since those are system triggers for pressure increases. It sounds like a feature that allows you to select how fast or slow the machine returns to baseline or prescribed pressure (the initial or starting APAP pressure between min and max).

Right, the "Pressure Decrease" (or actually "Airway Stable") Switch controls the speed of return to Pmin in the absence of detected events.

Fast Mode will allow 0.5 cm H2O decrease after 5 minutes with subsequent 0.5 cm H2O decrease each following minute.
Slow Mode will allow 0.2 cm H2O decrease after 5 minutes with subsequent 0.2 cm H2O decrease each following minute.

SAG

[DreamDiver]

Creating reports anyone can read using pdf creation software:

Most of us have adobe acrobat reader, but many of us cannot create pdf files. If you don't have adobe acrobat creator or another method for creating pdf reports, you can download an install a free pdf creator here:
http://sourceforge.net/projects/pdfcreator/

Here's a movie on how to install it.
http://www.cuw.edu/videoserver/fullplay ... ovieid=835

Once installed, pdfcreator acts like a printer, except, instead of printing to paper, the document is printed to a file on your computer, which you can then send to other people. When you're ready to create a pdf file of your report, simply pull down from 'file' to 'print'. Navigate to the 'pdfcreator', set your preferences and 'print'. You'll be asked where you want the document to be stored. Navigate to your preferred folder and save it there. (For instance, I usually save reports in 'My Documents/cpap/reports/'.) The document will automatically open the document in adobe acrobat reader if it's installed. Voila. You have a portable document anyone can read and you've saved a tree.

As to removing the more personal elements, like names, this can be done with other software like adobe illustrator or adobe acrobat composer.

If someone will print out a copy of a full report as a pdf file and pm me, I'll be happy to 'sanitize' any personal information and post it as a pdf and as images for the site.

[Snoredog]

Creating reports anyone can read using pdf creation software:

Most of us have adobe acrobat reader, but many of us cannot create pdf files. If you don't have adobe acrobat creator or another method for creating pdf reports, you can download an install a free pdf creator here:
http://sourceforge.net/projects/pdfcreator/

Here's a movie on how to install it.
http://www.cuw.edu/videoserver/fullplay ... ovieid=835

Once installed, pdfcreator acts like a printer, except, instead of printing to paper, the document is printed to a file on your computer, which you can then send to other people. When you're ready to create a pdf file of your report, simply pull down from 'file' to 'print'. Navigate to the 'pdfcreator', set your preferences and 'print'. You'll be asked where you want the document to be stored. Navigate to your preferred folder and save it there. (For instance, I usually save reports in 'My Documents/cpap/reports/'.) The document will automatically open the document in adobe acrobat reader if it's installed. Voila. You have a portable document anyone can read and you've saved a tree.

As to removing the more personal elements, like names, this can be done with other software like adobe illustrator or adobe acrobat composer.

If someone will print out a copy of a full report as a pdf file and pm me, I'll be happy to 'sanitize' any personal information and post it as a pdf and as images for the site.

There is also CutePDF writer for free, I've always had good results using CuteFTP and CutePDF stuff, you can download it here for free make sure you download both files including the converter:

http://www.cutepdf.com/Products/CutePDF/writer.asp

[DreamDiver]

There is also CutePDF writer for free, I've always had good results using CuteFTP and CutePDF stuff, you can download it here for free make sure you download both files including the converter:

http://www.cutepdf.com/Products/CutePDF/writer.asp

A third also free option is this one:
http://www.pdf995.com/

Each are equally free and equally excellent at creating pdfs using the print function.

[-SWS]

Right, the "Pressure Decrease" (or actually "Airway Stable") Switch controls the speed of return to Pmin in the absence of detected events.

Fast Mode will allow 0.5 cm H2O decrease after 5 minutes with subsequent 0.5 cm H2O decrease each following minute.
Slow Mode will allow 0.2 cm H2O decrease after 5 minutes with subsequent 0.2 cm H2O decrease each following minute.

That's definitely a change from the predecessor 420e model.

The text I have highlighted below in red caught my eye (excerpt from the downloadable sales card):

Direct USB connectivity using Sandman therapy software to:
- Direct data download
- Upload new settings
- Visualize actual session

Wonder if that feature is really embedded in the ordinary Sandman Therapy Software for $140 or if that feature requires a more expensive clinical version of the Sandman diagnostic series software.