Sandman Auto

[Snoredog]

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.

Silverlining pretty much had the same thing, seems the USB cable replaced the serial telephone jack vent hole
but had the Monitor mode for visualizing actual session.

I wonder if the clinical manual is not included in the way of the filename.pdf contained in the software directory like Silverlining? While a help file there, copied out to another directory it becomes a stand alone PDF manual, should explain all the parameters found on the new machine along with explanations of the new software.

[-SWS]

Silverlining pretty much had the same thing, seems the USB cable replaced the serial telephone jack vent hole
but had the Monitor mode for visualizing actual session.

I remember the manual mentioning something about the capability to record live. But I also thought a more expensive software package was required to accomplish that. Really vague about that feature, though. I don't recall anyone trying it. And I thought it was for lack of all the necessary software.

I wonder if the clinical manual is not included in the way of the filename.pdf contained in the software directory like Silverlining? While a help file there, copied out to another directory it becomes a stand alone PDF manual, should explain all the parameters found on the new machine along with explanations of the new software.

That sure would be nice to pass around for the curious among us!

[Snoredog]

Silverlining pretty much had the same thing, seems the USB cable replaced the serial telephone jack vent hole
but had the Monitor mode for visualizing actual session.

I remember the manual mentioning something about the capability to record live. But I also thought a more expensive software package was required to accomplish that. Really vague about that feature, though. I don't recall anyone trying it. And I thought it was for lack of all the necessary software.

I wonder if the clinical manual is not included in the way of the filename.pdf contained in the software directory like Silverlining? While a help file there, copied out to another directory it becomes a stand alone PDF manual, should explain all the parameters found on the new machine along with explanations of the new software.

That sure would be nice to pass around for the curious among us!

It has been included in every version of software I have owned going back to 3.1. For example, if you had a 50ft telephone cord connected to it with a computer in another room and machine was hooked up to someone, you could monitor and visually see their curve displayed on the screen, it has record and stop buttons, if you wanted to save that in the form of a screen snap say every 30 seconds you would have to use a 3rd party program. But live it is available on current version of the 420e's Silverlining. I assume it is in Sandman.

Hey if I had that PDF I'd send it to ya

[-SWS]

It has been included in every version of software I have owned going back to 3.1. For example, if you had a 50ft telephone cord connected to it with a computer in another room and machine was hooked up to someone, you could monitor and visually see their curve displayed on the screen, it has record and stop buttons, if you wanted to save that in the form of a screen snap say every 30 seconds you would have to use a 3rd party program. But live it is available on current version of the 420e's Silverlining. I assume it is in Sandman.

This may be a viable way to see exactly what's happening at much lower (real-time) epochs with people who have to turn IFL1 off. At typical adult breath rates of anywhere between 700 and 1200 breaths per hour, resolution of SL3's 96-hour detailed reports fall way short. Are you sure extra software wasn't required to retrieve and view the stored file? Wonder why nobody's been using it.

[StillAnotherGuest]

It has been included in every version of software I have owned going back to 3.1. For example, if you had a 50ft telephone cord connected to it with a computer in another room and machine was hooked up to someone, you could monitor and visually see their curve displayed on the screen, it has record and stop buttons, if you wanted to save that in the form of a screen snap say every 30 seconds you would have to use a 3rd party program. But live it is available on current version of the 420e's Silverlining. I assume it is in Sandman.

This may be a viable way to see exactly what's happening at much lower (real-time) epochs with people who have to turn IFL1 off. At typical adult breath rates of anywhere between 700 and 1200 breaths per hour, resolution of SL3's 96-hour detailed reports fall way short. Are you sure extra software wasn't required to retrieve and view the stored file? Wonder why nobody's been using it.

If you want to get a look at what's happening during the night without resorting to the "dsm Method of Nocturnal Monitoring" (wife with a flashlight, notepad and pencil), you can use TimeSnapper as suggested by becktrev a while ago:

How Do You Do That?

SAG

[ozij]

Wow SAG!
That's the first time I"ve ever seen that post! I've just finished reading it for the first time around - thanks a million for reviving it!!!

Edit
It's a pity becktrev's links no longer work.

O.

[-SWS]

you can use TimeSnapper as suggested by becktrev a while ago:

How Do You Do That?

Very nice! Thanks, SAG! And big, BIG kudos to becktrev for that thread as well. Great contribution IMO.

That's the first time I"ve ever seen that post! I've just finished reading it for the first time around - thanks a million for reviving it!!!

I missed that thread altogether as well. I must have been away from the message board around that time frame. Funny thing is I don't remember talking about the record-to-hard-drive feature either, as becktrev had mentioned. Regardless, becktrev's thread is a classic 420e contribution IMO!

Wonder if any of the "IFL1 terminators" out there might be interested in getting a few screen shots at the very beginning of a classic 420e pressure runaway sequence. Thanks again, SAG and becktrev!

[ozij]

I must have been away from the message board around that time frame

Same here.


O.

[ozij]

As suggested, I added
TakeSnapshotAlsoWhenIdle = True
to the settings.ini file (On my XP it's in Application Data\Timensapper subdirectory. Note: that file is replaced, without the crucial line, each time you change settings (e.g. telling it where to save today's data), so add the line after you've set everything else.

Timensnapper worked like a charm. Once it disappears from view, you can find it in the system tray, where you can stop it and exit it.

A friendly suggestion: before you start recording, make sure the 420E's time is synchronized to the computer's. You can then find the interesting tick on the details screen, and aim Timenapper at some seconds before the tick. The tick is put there at the end of the event.

O.

[StillAnotherGuest]

The Sandman Auto approach to snoring:

0.2 cm H2O increase every 20 seconds if snoring in absence of hypopnea.
0.3 cm H2O increase every 20 seconds if snoring in conjunction with hypopnea.
3.0 cm H2O maximum increase for snoring in absence of other obstructive events.
Pressure cannot exceed Pmax.

Seems to be less aggressive than the GK420E:

Increase of 1 cmH2O pressure after detection of snoring.
3 other pressure increases, each 2 cycles, if the run is not ended.
After this increase of pressure, a 1 minute period begins during which no increase of pressure due to snoring will be allowed.
Pressure cannot exceed Pmax.

Hmmm, 3 lefties in a row going up against the Brewers. I wonder whose idea THAT was.

Oh well, what's done is done...

SAG

[feeling_better]

...
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 just happen to read this very interesting thread for the first time now. I wonder how much of my AI is actually misclassified HI, under my M-series...

Note: The modern signal processing techniques such as FFT (fast fourier transforms) can be extremely more sensitive than typical waveform analysis for detecting the cardiac signal here. The cardiac frequency at best changes slowly and is in a well defined narrow range, way out of the breathing frequency. So under wide range of flow limitations the cardiac signal can be reliably monitored for amplitude, and phase. [FFT was the method I had used first time in the 80's for VEP (visual evoked potentials -- brain wave) analysis, almost all of the others at that time was using waveform shape analysis with complex algorithms.]

[-SWS]

...
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 just happen to read this very interesting thread for the first time now. I wonder how much of my AI is actually misclassified HI, under my M-series...

Note: The modern signal processing techniques such as FFT (fast fourier transforms) can be extremely more sensitive than typical waveform analysis for detecting the cardiac signal here. The cardiac frequency at best changes slowly and is in a well defined narrow range, way out of the breathing frequency. So under wide range of flow limitations the cardiac signal can be reliably monitored for amplitude, and phase. [FFT was the method I had used first time in the 80's for VEP (visual evoked potentials -- brain wave) analysis, almost all of the others at that time was using waveform shape analysis with complex algorithms.]

The Puritan Bennett algorithm discussed in this thread is radically different than the M-Series detection algorithm. The M-Series doesn't look for cardiac oscillations and performs only limited obstructive type validation via flow wave-shape analysis. Regarding FFT, I believe at least one of the 420e patent descriptions mentioned that as a typical embodiment of processing resident flow pulsations in the cardiac oscillation frequency range.

Also bear in mind that the Puritan Bennett algorithm cannot completely dispense with template-based wave shape analysis to probability-differentiate occlusive-airway flow shapes. Here you have: 1) occlusive airway wave-shape analysis (specifically the differentiation of sinusoid flow shapes from typical shoulder and flattened shapes---and even less-determinate shapes), coupled with 2) FFT or equivalent frequency-signal filtering and analysis of resident cardiac oscillations. One technique focuses on signal processing signs of an open airway while the other technique focuses on processing alternate signs of a closed airway. The two complementary techniques are thus employed in tandem toward algorithmic differentiation of central versus obstructive events with this Puritan Bennett algorithm.

Your comment also questions a possible interrelationship of hypopnea specificity impacting apnea sensitivity (or vice versa, considering amplitude variability's typical impact on dynamic maintenance of baselines). I agree that would be an inherent issue for any APAP detection algorithm.