Unusual ResScan Obstructive Pattern

[robysue]

Avi,

As others have pointed out: The data you posted did NOT include the Flow graph. The only way to see the FOT bumps on an apnea that an S9 Elite or S9 Autoset has scored as a CA is to look at the Flow graph AND zoom in on the central apnea so that it takes up all or most of the the width of the graph. The graph posted by idamtnboy, for example is a 30 second long piece of the Flow graph that includes a 17 second long central apnea with the FOTs clearly visible.

The data you posted includes Pressure, Leak, Minute Ventilation, AHI, Events, Snore, and Flow LIMITATION data shown in a five minute window. It does NOT contain the Flow graph itself, which is the only graph that would show the FOTs. Moreover, the only two apneas in this five minute window were scored as OBSTRUCTIVE apneas. And the FOTs don't show up on OAs---that's exactly how the machine decides they are OAs instead of CA: The FOTs do NOT get through the obstruction and hence the air movement (flow) remains flat. So there are no FOT bumps in this data to be seen in the first place---you have the wrong graphs and the wrong kind of apneas for showing the FOTs.

But even if you did have the Flow data and even if there was a Central Apnea scored in this five minute window, the FOTs would still not show up if the data window is set for five minutes. You just can't see four second events at that scale.

[Lizistired]

[quote="robysue"]
... Moreover, the only two apneas in this five minute window were scored as OBSTRUCTIVE apneas. And the FOTs don't show up on OAs---that's exactly how the machine decides they are OAs instead of CA: The FOTs do NOT get through the obstruction and hence the air movement (flow) remains flat. So there are no FOT bumps in this data to be seen in the first place---you have the wrong graphs and the wrong kind of apneas for showing the FOTs. [quote]

I'm trying to understand this. Aren't these FOTs on this OA?

[idamtnboy]

... Moreover, the only two apneas in this five minute window were scored as OBSTRUCTIVE apneas. And the FOTs don't show up on OAs---that's exactly how the machine decides they are OAs instead of CA: The FOTs do NOT get through the obstruction and hence the air movement (flow) remains flat. So there are no FOT bumps in this data to be seen in the first place---you have the wrong graphs and the wrong kind of apneas for showing the FOTs.

I'm trying to understand this. Aren't these FOTs on this OA?

In contrast to the several times I've misspoken (or is it miswritten?), I think this is the first time I've seen robysue trip up. The FOT is what the S9 uses to differentiate between a CA and an OA. In order to do that it has to start, and it shows in the flow graph, regardless of the type of apnea. You'll also notice the FOT doesn't start until about 4 or 5 seconds after the apnea starts. It takes that long before the flow analysis routine (I call it the FAR) decides there's a problem and it's time to investigate.

[Lizistired]

OK, thanks for clearing that up.

[avi123]

Found the FLOW with lots of FOTS. See at the last Flow graph:

https://docs.google.com/viewer?a=v&pid= ... vxlw&pli=1

[-SWS]

There is no just "Flow".

Then you still haven't found the necessary "detailed" graphs part of your ResScan reports. That "flow" graph you are looking for is not offered on data recordings that are older than 7 days. So look for: 1) the "detailed" tab, but specifically 2) data sessions no older than 7 days.

I have haves graphs of 4 events: Obs, Centr, Hypo, and Unknown.

FOT is Resmed's ONLY way of yielding the "Centr" apnea distinction. So if your Elite is counting "Centr" apneas, then it is definitely employing FOT to make that distinction.

BTW, I don't see in this conversation actual graphs showing FOTs taken from S9 AoutSets via ResScan.

Here it is on page two of the current thread: viewtopic.php?f=1&t=61477&start=15#p575988
The FOT part would be those small-amplitude 4 Hz oscillations on the detailed "Flow" graph in the above link.

Keep looking... The ability to distinguish "Centr" apneas most certainly implies FOT on any Resmed machine.

[idamtnboy]

On my S9 Elite I have Flow Limitation or Minute Ventilation. There is no just "Flow".

Make sure when you download the data from your SD card into Resscan that the option to "Include high resolution data" is checked in the options. Selecting "Summary plus detailed data" is not enough! Then you will have the option to show the Flow graph in Resscan, but only for days for which you downloaded the high resolution data off the SD card.

I'll bet when you see the download dialog box you do not see the words, "All available data" inside the selection box.

[avi123]

del

[idamtnboy]

Hey guys with your S9 AutuSet machines, if you set your machine in CPAP mode then you get an equivalent of S9 Elite machine. Any chances to see actual FOT curves?

The FOT graph I posted earlier is the S9 Autoset in CPAP mode.

avi, please read veeeeerrrrrrrryyyyyyy slooooooowwwwwwlllllyyyyyyyy and carefullllllllllllllllllllyyyyyyyyyyyyyyyyyy!!!!!!!!!!!!!!!!!!!!

You see the FOT ONLY, as in O-N-L-Y, during an apnea on the FLOW, as in F-L-O-W graph. You need to post the flow graph. There are plenty of instructions in this post to date to guide you in being able to see them.

[Lizistired]

Idamtnboy, I admire your patience. Breathe.

[-SWS]

Hey guys with your S9 AutuSet machines, if you set your machine in CPAP mode then you get an equivalent of S9 Elite machine. Any chances to see actual FOT curves?

AVI, take a look at the S9 Elite graph in the first post at the beginning of this thread. There you'll see FOT on the detailed "flow' graph for an S9 Elite.

[Bandnuts]

Short update from the OP....

The doctor and sleep group got the sleep data from my S9 Elite. I had to drive it over to them as they were unable to handle an internet download from one of my web sites.

They confirmed the patterns were central and the Cheyne-Stokes issues (not a difficult confirmation based on the flow). They set me up to re-take a sleep test (tomorrow) to see how the ResMed VPAP™ Adapt SV machine might better handle the specific breathing issues I have and to confirm the need for me to change over to that type of machine. They stated that the S9 Enhanced Autoset would not help and (most likely) the VPAP was needed (once confirmed with a new sleep test).

What was interesting is that the E9 Elite registered 99.99% these as obstructive apneas (note the tile of this topic) yet every indication from the patterns (and they were given HOURS of this pattern to review) was that the waves were central. I was told that they provided my data direct to ResMed in order for them to review machine read-outs. Don't know if anything will come of that, but it would be nice if it did.

All-in-all, progress is being made. More follow-up will be provided after my sleep test and once a new machine is put into operation.

[billbolton]

What was interesting is that the E9 Elite registered 99.99% these as obstructive apneas (note the tile of this topic) yet every indication from the patterns (and they were given HOURS of this pattern to review) was that the waves were central.

Cheyne-Stokes breathing is something which is significantly different in SBD terms to the aperiodic OSA condition that xPAP machines are designed/intended to treat.

It seems that you were misdiagnosed, as a PSG would have shown the Cheyne-Stokes breathing quite clearly and any competent sleep technician, let alone a sleep clinician, should have spotted the pattern from the PSG data.

Basically, you were just given the wrong sort of device to treat your particular SDB condition, so there's nothing at all surprising that an xPAP machine had difficulty in deciding what your SDB events were.

Cheers,

Bill

[avi123]

Short update from the OP....

The doctor and sleep group got the sleep data from my S9 Elite. I had to drive it over to them as they were unable to handle an internet download from one of my web sites.

They confirmed the patterns were central and the Cheyne-Stokes issues (not a difficult confirmation based on the flow). They set me up to re-take a sleep test (tomorrow) to see how the ResMed VPAP™ Adapt SV machine might better handle the specific breathing issues I have and to confirm the need for me to change over to that type of machine. They stated that the S9 Enhanced Autoset would not help and (most likely) the VPAP was needed (once confirmed with a new sleep test).

What was interesting is that the E9 Elite registered 99.99% these as obstructive apneas (note the tile of this topic) yet every indication from the patterns (and they were given HOURS of this pattern to review) was that the waves were central. I was told that they provided my data direct to ResMed in order for them to review machine read-outs. Don't know if anything will come of that, but it would be nice if it did.

All-in-all, progress is being made. More follow-up will be provided after my sleep test and once a new machine is put into operation.

Let's hope that this time you'll get the right treatment

[AMUW]

The doctor and sleep group got the sleep data from my S9 Elite... They confirmed the patterns were central and the Cheyne-Stokes issues (not a difficult confirmation based on the flow). They set me up to re-take a sleep test (tomorrow) to see how the ResMed VPAP™ Adapt SV machine might better handle the specific breathing issues

Cheyne-Stokes breathing is something which is significantly different in SBD terms to the aperiodic OSA condition that xPAP machines are designed/intended to treat. It seems that you were misdiagnosed, as a PSG would have shown the Cheyne-Stokes breathing quite clearly and any competent sleep technician, let alone a sleep clinician, should have spotted the pattern from the PSG data.

Having had ResMed S9 Autoset flow curves similar to Bandnuts', I am really interested to see what his upcoming PSG night determines.
But not having had any cardio-vascular or cerebro-vascular problems dx'd before, I wonder about the above story:
- can a sleep doctor or sleep tech UNMISTAKABLY see Cheyne-Stokes patterns when provided just the ResMed flow curves? without SAO2% and EEG?
- are most multi-channel PSG studies set up with automatic software tests and sleep tech attention to "ring a bell" on Cheyne-Stokes, as Bill implies? (my PSG used REMbrand). WHAT ARE CHANCES THAT THESE PATTERNS ONLY APPEAR UNDER CERTAIN, YET UNCLARIFIED, SLEEP AND CPAP CIRCUMSTANCES?
In trying to differentiate Cheyne-Stokes from CPAP-induced centrals, those of you more familiar with the issue may care to check out the following article:
http://pats.atsjournals.org/cgi/content ... 2/226#FIG1
Central Sleep Apnea and Cheyne-Stokes Respiration D Yumino, TD Bradley
Proc American Thoracic Society 5:226-236 (2008)