Input Needed for New Encore Pro Analyzer

[cchase]

This messge constitutes topic and scope creep, but is it reasonable to have a user-entered field that tracked mask type used, and maybe one or more charts such as AHI by mask? I realize this would mean writing to the database, which may not be a good thing, or adding another instance of SQL Server, which sounds like a lot of complexity. Just an idea. I've often generated an Excel sheet to do this, but charts are better.

You guys like to keep me working don't you

Hi James and others-

I really appreciate your time and effort to develop Encore Pro Analyzer.

I don't know the answer to Q1-time in apnea, but you might be able to infer it by examining the total events, seconds in apnea, and then compare it to the average time in apnea per day reported in the REMstar Auto Statistics. You should be able to determine which events are used to calculate the average.

Q2-AHI calculation. I agree with the discussion; the sum of apneas divided by total hours is the only way to produce an accurate AHI.

Q3-Treatment Time per day. I'd go with a low threshold such as 1 hour for the reasons you suggest.

Adding to the wish list:

1. I'd appreciate better descriptive statistics. Min, max, mean, and SD would be very helpful. I'm particularly interested in tracking variability of measures over time, expecting that variability might be greater at the beginning of treatment or starting with a new mask, but perhaps will stabilize over time. It also might help me to identify changes in life-style (diet, exercise) and their effect on treatment stability.

2. One display in EncorePro that has some use is to look at a graph of a night of data. There is no need to replicate this in Analyzer (unless you are truly interested in replacing EncorePro altogether), but the real value of these graphs for me has been the opportunity to examine possible event triggers during the night. The big one is mask leaks. We all suppose that if a mask produces a sufficient leak over a long enough period of time, then treatment will be compromised, my airway will close off, and trigger an event. Is this what really happens? If we could plot leaks by events, then might begin to see patterns that would be very instructive about the role of leaks in apnea events.

Perhaps being able to plot other measures, such as variable breathing with AHI, would be useful as well. The week with my highest AHI was also the week I spent more time in variable breathing. A couple of recent threads suggested that variable breathing is used by the software to adapt pressure adjustment procedures when erratic breathing makes tracking an apnea event more difficult to do.

Thanks again for your work. You help us all.

-Chris

[greyhound]

That makes sense to me. It's also (sort of) consistent with the fact that Encore Pro definesn NR as non-responsive apnea/hypopnea.

[jskinner]

I think you have an answer in the posted data:

I'm still not convinced. I did a query of my database that now has data from numerous users. I found 245 cases where there where zero seconds in apnea but still lots of recorded hypoapneas... I don't think seconds in apnea includes seconds in hypopneas based on that query...

[curtcurt46]

See my input under Encore Pro Analyzer for Bipap.

[jskinner]

Q2-AHI calculation. I agree with the discussion; the sum of apneas divided by total hours is the only way to produce an accurate AHI.

Agreed. I have now switched to this way of calculating Average AHI.

Q3-Treatment Time per day. I'd go with a low threshold such as 1 hour for the reasons you suggest.

Ok, I have gone with 1 hour for now. I may make it user definable later.

1. I'd appreciate better descriptive statistics. Min, max, mean, and SD would be very helpful.

Easy enough to do. I'll have to think how I might do that in the UI. I don't want to over crowd each chart with too much info. I think putting that on each chart would be too much?

We all suppose that if a mask produces a sufficient leak over a long enough period of time, then treatment will be compromised, my airway will close off, and trigger an event. Is this what really happens? If we could plot leaks by events, then might begin to see patterns that would be very instructive about the role of leaks in apnea events.

Note sure how to do this but it sounds useful. Needs more thought.

Perhaps being able to plot other measures, such as variable breathing with AHI, would be useful as well. The week with my highest AHI was also the week I spent more time in variable breathing. A couple of recent threads suggested that variable breathing is used by the software to adapt pressure adjustment procedures when erratic breathing makes tracking an apnea event more difficult to do.

Hmm, yeah doable I guess. %variable breathing vs AHI? What do others think? If I understand it correctly variable breathing can indicate REM or being awake. In REM I would expect a higher AHI and in wakefulness no AHI. Since we can't tell the difference I'm not sure how accurate the results would be?

-james

[dllfo]

I downloaded the Microsoft .Net Framework for My Encore and it works fine.
But the new program cannot find it, it is telling me to download it again.

What is puzzling me is that this program was designed to run with the same inputs as My Encore...NO?

Or is the Microsoft.Net Framework a newer version???

Ideas?

[ozij]

I think you have an answer in the posted data:

I'm still not convinced. I did a query of my database that now has data from numerous users. I found 245 cases where there where zero seconds in apnea but still lots of recorded hypoapneas... I don't think seconds in apnea includes seconds in hypopneas based on that query...

Either needingu's data was wrong, or there is an error in your query -

By 245 cases, do you mean 245 hypopneas? Or do you have 245 people who have 0 apneas, some hypopneas, and no time spent in apnea?

How do you explain needingu's data?

O.

[jskinner]

But the new program cannot find it, it is telling me to download it again.

What is puzzling me is that this program was designed to run with the same inputs as My Encore...NO?

Or is the Microsoft.Net Framework a newer version???

Ideas?

Encore Pro Analyzer need the 2.0 Version of .NET framework.

-James

[cchase]

1. I'd appreciate better descriptive statistics. Min, max, mean, and SD would be very helpful.

Easy enough to do. I'll have to think how I might do that in the UI. I don't want to over crowd each chart with too much info. I think putting that on each chart would be too much?

The descriptive stats could be done in a couple of different ways:

1. part of a table that summarizes values over a period of time.
2. standard deviation could be put as error bars on the histogram.

We all suppose that if a mask produces a sufficient leak over a long enough period of time, then treatment will be compromised, my airway will close off, and trigger an event. Is this what really happens? If we could plot leaks by events, then might begin to see patterns that would be very instructive about the role of leaks in apnea events.

Note sure how to do this but it sounds useful. Needs more thought.

I'd have to play with some data to see what works best. Initially, I've been thinking about a simple graph that plots time on the x-axis and leaks and AHI events on the y-axis as separate lines (you could put the leak scale on the left-side of the chart and the AHI on the right side). The data points are averages of each measure over a short period of time during treatment (say 5 or 10 minute increments). On this graph, if there is a leak threshold where my AHI begins to increase, it should be easy to spot.

Perhaps being able to plot other measures, such as variable breathing with AHI, would be useful as well. The week with my highest AHI was also the week I spent more time in variable breathing. A couple of recent threads suggested that variable breathing is used by the software to adapt pressure adjustment procedures when erratic breathing makes tracking an apnea event more difficult to do.

Hmm, yeah doable I guess. %variable breathing vs AHI? What do others think? If I understand it correctly variable breathing can indicate REM or being awake. In REM I would expect a higher AHI and in wakefulness no AHI. Since we can't tell the difference I'm not sure how accurate the results would be?

Yes, I was thinking about what other overlapping plots might be useful. I don't have a good reason to think variable breathing would be all that useful at this point.

Although I can't be of much help with the programming, I may be of some use to you in data presentation. PM me if there is something I can help with.

Best,

-Chris

[jskinner]

Either needingu's data was wrong, or there is an error in your query -

By 245 cases, do you mean 245 hypopneas? Or do you have 245 people who have 0 apneas, some hypopneas, and no time spent in apnea?

How do you explain needingu's data?

My 245 value was row entries in the SleepTrendsPressureStatusTable in the Encore Pro database. The SQL that I used was:

select SecondsInApnea, ApneaIndex, HypopneaIndex, NRAHIndex from SleepTrendEventLog2 where SecondsInApnea=0 AND HypopneaIndex>0

[StillAnotherGuest]

Perhaps being able to plot other measures, such as variable breathing with AHI, would be useful as well. The week with my highest AHI was also the week I spent more time in variable breathing. A couple of recent threads suggested that variable breathing is used by the software to adapt pressure adjustment procedures when erratic breathing makes tracking an apnea event more difficult to do.

Hmm, yeah doable I guess. %variable breathing vs AHI? What do others think? If I understand it correctly variable breathing can indicate REM or being awake. In REM I would expect a higher AHI and in wakefulness no AHI. Since we can't tell the difference I'm not sure how accurate the results would be?

According to the printed algorithms, Variable Breathing% really defines how long you're in a particular Mode (VBM) rather than having variable breathing per se:

Rantings on Variable Breathing

Perhaps in order to get any value looking at VB, you would have to plot VBM against real time (to know exactly when the machine is in VBM), and/or calculate number of events during VBM vs Pressure Titration Mode. Knowing when the machine is in VBM could help you differentiate Wake/NREM/REM sleep stages (and decide its relevance). Or if all of an increased AHI occurs during VBM (when Pressure Titration Mode is suspended), you might have to wonder if the Respironics algorithm is for you (like does it think Cheyne-Stokes Respiration is VB or Non-Responsive Apnea?)(Or if it suspends treatment, does it also suspend reporting events?)(Or better yet, if treatment is suspended, how can it determine a Non-Responsive Apnea?)

This is like holding two mirrors together.
SAG

[jskinner]

How do you explain needingu's data?

Here is a counter example that pretty much proves the opposite to me. Its from the one (and only one) night where I had no apneas

http://james.istop.com/apnea/reports/My ... lyNov5.jpg

Notice that I still have 5 hypopneas but no seconds in apnea.

[greyhound]

James, I'm surprised you have MyEncore (version 1.5B7) data for time in apnea, flow limitations, and variable breathing. My daily reports always show either zero or NA, but never any "real" data.

[jskinner]

James, I'm surprised you have MyEncore (version 1.5B7) data for time in apnea, flow limitations, and variable breathing. My daily reports always show either zero or NA, but never any "real" data.

Actually I had to temporarily rename a database table to get that. MyEncore can't get that information on an M Series because its in a new (but identical) table ...

So under 'normal' circumstances I wouldn't have it either.

[ozij]

Very strange. Or as Alice in Wonderland said: curiouser and curiouser.


According to needingu's profile, the machine in question is an Auto Bi-Pap, not an M series one.

Edit:We know Respironics in not reporting time spent in apnea in Encore Pro - at least, I think we know, since this is what folks said. Edit: I don't have the software, or machine - and was later on corrected by greyhound in this thread. O.

Could it be that nobody in Respironics has yet decided what to compute for "time spent in apnea" and the the rules, at this point are being switched around depending on the machine (or firmware)?

Could it be that the M series with ihas a separate "time spent in hypopnea" field somewhere?

O.

_________________

CPAPopedia Keywords Contained In This Post (Click For Definition): respironics, Encore Pro, Hypopnea, auto