Missing Data Again

This is from another company's premarketing equivalence submission. I assume Respironics would say something similar.
Caveat: This might relate to therapuetic software, not the reporting module, but is worth checking.

All software was tested in accordance with the May 29, 1998 “Guidance for the Content of Premarket submissions for Software Contained in Medical Devices” published by the Office of Device
Evaluation.

O.

DreamDiver wrote:An overly detailed explanation of the Respironics M-Series Pro firmware and Encore Pro software:

H. There is a glitch either in how the card is being read, or how the data is stored on the card. If it's about how the card is being read by Encore Pro, it's a software glitch. If it's how the data is being stored, it's a firmware glitch. I suspect it may be a firmware glitch. Several cpaptalk members have talked about this before. Every twenty eighth day, one or more days of high-res and low-res data get botched. If you continue storing data after the twenty eighth day, sometimes part of the data will be restored, but invariably, at least one day of hi-res and low-res data will be lost - usually the twenty eighth day - and sometimes other contiguous days.

Thank You DreamDiver - that is the best description/explanation of the way the card works I have ever seen.

I decided to put in a clean card last nite - got my detailed data this morning. Only 6 pages total starting over on a new card until that data builds up again. Maybe I will switch back to the old card tonite.

But I guess that is the problem - running out of room on the card. Whoever it was that said erasing the card helped was right on. Seems that swapping the card out should help also.

I have about 4 missing nights data since last June. Lately no missing data, here is my daily routine

1) Wake up in the morning, turn off APAP (start/stop button) and power off the machine.

2) If I have time in the morning, I will take the card and download the data. I make it a point to download data at least once a week. By the weekend, I uncheck the check box not keep compliance data.

3) The APAP is switch on at night when I ready to sleep.

BTW the APAP firmware is version 4.01. I only erase the card when missing data happen. Hardly need to erase card this days.

After reading that outstanding post by DreamDiver the conclusion I have reached is that due to poor programming routines in the firmware daily details are no longer recorded when there are too many sessions, for what ever reason.

Too many sessions could be a nap or two couple times a week, or simply turning the machine on (with the card in it) creating another session. What I don't understand is why it just started recording in the middle of the nite (~4am) on me at least two other times.

Perhaps something that is going on when trying to write data to the card. Some other data may have expired?

But it does appear (to me) that the routine that stores the daily details on the card is poorly written. We think it should overwrite the oldest data but it apparently simply deposits them into the bit bucket.

Interesting way to handle things - but that is what happens when programmers have to meet deadlines and the QC is not up to par.

When in doubt - ship it out!!!

Respironics programmers have been the issue on all of this I suspect. They didn't learn basic math to be able to program Encore Pro correctly and I bet it is the same idiots who wrote the routines for the M series data.

One has to hope that the programmers for the algorithms to respond to events actually knew what they were doing. However, I have been left wondering about that for quite a while.

Different machines may have different quirks. I gave the quirks I found with the M-Series Pro. YMMV.

If the data is suspect, it's suspect for all the data - not just for the few days that don't show. If we cannot get Respironics to listen to us and CPAP.com doesn't feel it is appropriate to champion our concerns, we likely do have a case for a class action remedy. I'd rather that they just take patients' concerns seriously than push it under the rug.

Another way around the problem is to use two cards - one for daytime naps and one for consistent nights. That way you'll get all your data for every session. You would still have to dump them before every 28th day though to be sure you don't lose data.

GumbyCT wrote:What I don't understand is why it just started recording in the middle of the nite (~4am) on me at least two other times.

GumbyCT,

Are the '4am-started' sessions typically the first session of any card dump?
That might be consistent RRD theory. If it happens on the most recent night of your card dump, I'm not sure what that may imply.

Other possibilities:
Turned it off over an hour, then back on in your sleep?
Hour-long electrical outages around three am in your neighborhood?

Well I don't know what I'm doing wrong (or right) but I have been using my AFLEX machine every night since end of January and I still have not lost any data (knocking on wood) ...

DreamStalker wrote:Well I don't know what I'm doing wrong (or right) but I have been using my AFLEX machine every night since end of January and I still have not lost any data (knocking on wood) ...

This suggests to me the latest Aflex machines don't have the firmware glitch.

DreamDiver wrote:

DreamStalker wrote:Well I don't know what I'm doing wrong (or right) but I have been using my AFLEX machine every night since end of January and I still have not lost any data (knocking on wood) ...

This suggests to me the latest Aflex machines don't have the firmware glitch.

Tho there are other possibilities -
I think it is highly unlikely there is a different firmware version for just for A-flex. fwiw - my bipap has 4.03 too.

1. The User doesn't create more than one session (No Naps).
2. The User is simply not aware the data is missing. Unless you download your data daily, you are not likely to even know it is NOT there. This is the more likely scenario.

When you dl card data daily you are more likely to notice -
A. Your total page count has changed - my norm is 13 going down to as few as 10. That is what confuses me- if it is supposed to overwrite the older data why does the page count even change?
B. Last nites daily details are not there but the compliance data shows up. This tells me my machine was not only plugged in but "In Use", when it 'M'ysterioulsy starts recording 3 or 4 hours after I began using it.

All true!

GumbyCT wrote:

DreamDiver wrote:This suggests to me the latest Aflex machines don't have the firmware glitch.

Tho there are other possibilities -
I think it is highly unlikely there is a different firmware version for just for A-flex. fwiw - my bipap has 4.03 too.

1. The User doesn't create more than one session (No Naps).
2. The User is simply not aware the data is missing. Unless you download your data daily, you are not likely to even know it is NOT there. This is the more likely scenario.

When you dl card data daily you are more likely to notice -
A. Your total page count has changed - my norm is 13 going down to as few as 10. That is what confuses me- if it is supposed to overwrite the older data why does the page count even change?
B. Last nites daily details are not there but the compliance data shows up. This tells me my machine was not only plugged in but "In Use", when it 'M'ysterioulsy starts recording 3 or 4 hours after I began using it.

4.01 for me

GumbyCT wrote:

DreamDiver wrote:

DreamStalker wrote:Well I don't know what I'm doing wrong (or right) but I have been using my AFLEX machine every night since end of January and I still have not lost any data (knocking on wood) ...

This suggests to me the latest Aflex machines don't have the firmware glitch.

Tho there are other possibilities -
I think it is highly unlikely there is a different firmware version for just for A-flex. fwiw - my bipap has 4.03 too.

1. The User doesn't create more than one session (No Naps).
2. The User is simply not aware the data is missing. Unless you download your data daily, you are not likely to even know it is NOT there. This is the more likely scenario.

When you dl card data daily you are more likely to notice -
A. Your total page count has changed - my norm is 13 going down to as few as 10. That is what confuses me- if it is supposed to overwrite the older data why does the page count even change?
B. Last nites daily details are not there but the compliance data shows up. This tells me my machine was not only plugged in but "In Use", when it 'M'ysterioulsy starts recording 3 or 4 hours after I began using it.

It seems odd too that ALL reports of "missing data" seem to resolve themselves in 2 days. So throw that into the mix - if nothing is done - the problem just goes away in 2 days.

ring!.......ring!.........ring!

Respironics Customer Support....

Hi I have this new machine that seems to lose a couple nights data every few weeks, I think something may be wrong with it...

RCS: mmmm.... we have NEVER heard of that problem before is it plugged in?

ah huh I think so,

RCS: are you sure you were NOT sleep walking?

sleep walking? what does that have to do with my machine losing session data?

RCS: that is the only reason our machine would ever lose data you had to be sleep walking....

if you say so but Encore software said I was there sleeping but the data is missing.

RCS: are you a patient?

yes

RCS: we don't talk to patients! contact your DME click!

wait!!!......wait!!! my DME is Apria!!

if you'd like to make a call....

Snoredog wrote: RCS: that is the only reason our machine would ever lose data you had to be sleep walking....

Yeah, when in doubt blame the patient. My DME did that to me. I asked why the machine was raising the pressure while I was awake. Oh you must have fallen asleep for a second and not realized you were asleep. Yeah right.

DreamStalker wrote:Well I don't know what I'm doing wrong (or right) but I have been using my AFLEX machine every night since end of January and I still have not lost any data (knocking on wood) ...

You are one of the lucky ones DreamStalker, I got my new Apap with Aflex April 3, and last night made the 3rd time it has missing data. With my other straight Cpap, it only happened maybe 3 times in a 5 month period. I am not doing anything different, when I checked it just now, it was about 4 hours after I got up this morning. I know that if I take it out too soon, it loses data. But after 4 hours? Analyzer showed time in apnea as 1.2 minutes, but no event numbers.