SH 1.1 and OSCAR divide sleep sessions that go over noon.

[pholynyk]

I was thinking about this a while back. It would be possible to shift the day split time... at least for the Daily display graphs. And you pretty well give up on any statistical reporting. They could be recomputed... BUT you have to never have a summary-only day when you forget to put the card back in, or leave it locked, or otherwise miss a day. Because the machine splits its data recording and statistical calculations at machine noon, and there is no way to recreate session statistics if the session data is not there.

It's a big problem with no easy solution.

Are you sure you can't reset machine noon to be 18:00 local time? That, we could probably allow for....

Edit: Ummm, this applies to ResMed machines. Phillips-Respironics machines probably have other quirks.

[Blazing Black Beard]

I doubt that the ability to set days to be split at times other than 12noon would be very useful. It wouldn't help in many cases, including my own, where my days can range from anywhere between 20 hours and 30 hours due to massive circadian rhythm problems. In this instance, patients would have to constantly adjust the daily session cutoff threshold in OSCAR, which isn't helpful and just complicates things needlessly.

With the newer Resmed Airsense 10 machines, a lot of days worth of sleep data is held on the memory card for many days and it's not just summary data.

The Resmed S9 machine only has a couple of days worth of data stored, maybe due to the very small SD card capacity. At least this is my experience because looking any further back than a couple of days only loads and displays summary data from the SD card, which is pretty useless.

The Resmed Airsense 10 however shows a lot of recorded data for over a week, and not just the summary data, as the memory card supplied is SDHC, with much more capacity than the standard SD card supplied with the S9.

Having the ability to highlight and select areas of the full data from sleep sessions, data that breaches 12noon, and then combining them to show as one session is required in OSCAR, as it would solve half the problem. Even implementing a semi-inteligent system where close proximity data would be combined automatically into one sleep session, if it appears within the same hour, would be of great benefit and make sessions more readable.

However the other half of the problem is when patients don't load their SD card data into OSCAR in a timely manner, before the previous sessions are replaced with new sessions, due to limited SD card capacity or inherent capacity issues with different machines. Maybe using a larger memory card could help and maybe board members can report their success with various capacity memory cards and share with us their experiences trying to upgrade the recording capacity. Maybe we could even provide a table to show which SD card sizes and standards are compatible with each machine.

Currently it appears as though:

Resmed S9 Autoset - SD (regular capacity) 
Resmed Airsense 10 Autoset/Elite - SDHC (High Capacity)

I have not checked the formatted sizes of these as I have never had any problems with them.

Also maybe we can share experiences and someone can compile a table and post it here that will show us how often to load SD card data from each machine, to avoid overwriting older data before it is loaded into OSCAR. This is not something that OSCAR should even be attempting to address, as remembering to load SD card data into OSCAR in a timely manner is purely the responsibility of the patient and nothing to do with the developers. Nothing the developers can do will enable OSCAR to retrieve or replicate data already overwritten by the machine.

So, can we have a table uploaded to combat this and at the same time implement cross-12noon sleep session combining and splitting please?

[DeepBreathing]

BBB the issue with the S9 is not a function of card capacity per se. The machine itself overwrites high resolution data after (nominally) seven days, regardless of the capacity of the card. It's more likely that the machine designers made that decision because of small capacity cards available when the machine was developed and did not look to the future. On the face of it, it was lazy programming. But of course there may be reasons we're not aware of.

[Blazing Black Beard]

Well the new machines clearly support more data retention but this isn't really the issue we're discussing.

The ability to be able to group and split sessions regardless of crossing the 12noon threshold is the main issue to address.

[DeepBreathing]

Well the new machines clearly support more data retention but this isn't really the issue we're discussing.

My humble apologies - I thought this was the point you yourself raised in your previous post!

The Resmed S9 machine only has a couple of days worth of data stored, maybe due to the very small SD card capacity.
...
Maybe using a larger memory card could help ...

No it won't help, for the reason I just told you above - putting a larger card in an S9 won't increase the number of days high resolution data retained on the card. Other machines don't seem to have a problem, with members reporting cards taking a year or more to fill up.

[Blazing Black Beard]

My humble apologies - I thought this was the point you yourself raised in your previous post!

No, the point of my post was primarily to show there's a real need for a grouping and splitting sleep session data feature to fix the 12noon problem and an automatic gap threshold detection feature that can be set to automatically overcome short gaps in therapy and combine them properly to form a complete sleep session recording rather than arbitrarily splitting them into needless separate sessions that then show skewed summaries and are hard to read.

The conversation about data capacity was a side issue that I just trivially added because I have never really looked into it and was just curious, which is why I clearly stated that I have never looked into the formatted capacity of any Resmed SD or SDHC card.

No it won't help, for the reason I just told you above - putting a larger card in an S9 won't increase the number of days high resolution data retained on the card. Other machines don't seem to have a problem, with members reporting cards taking a year or more to fill up.

You addressed this in your last post, which I have not countered. Why are you repeating yourself? You have already made your point and it was duly noted before my last response.

[NoRestForWicked]

The lack of grouping function in SleepyHead 1.1, and hence also Oscar, which was/is present in SleepyHead 1.0 (which I still use) was the original problem I posted about. As you say, this has (probably) nothing to do with the ResMed 12 o'clock day split, as the split has always been present in ResMed CPAP machine data acquisition. The problem of SleepyHead 1.1/Oscar no more being able to combine close by sessions has also other ramifications besides splitting the CPAP data: it completely messes up the SpO2-data if you are recording it over noon. The grouping function was lost somehow in the SleepyHead 1.0 / 1.1 phase, as Oscar is practically SleepyHead 1.1+, just with a somewhat different developer team.

I don't know how things work in ResMed's own clinical datasystem. ResMed has its own SpO2 module, which in hospitals is often coupled to a very compact Nonin Spo2 measuring unit meant for hospital use. I have used also this system (my clinic borrowed it for me for a study for a few nights at home) in addition to my own Contec CMS 50 I wrist SpO2 meter I use all the time. Both SpO2 measuring units produce similar data in SleepyHead 1.0, providing both the ResMed and Contec clocks have the same time (the CMS 50 I data is imported through the SleepyHead SpO2 data import function; the ResMed SpO2 module data is written on the CPAP datacard of the CPAP machine itself and imported to the SleepyHead via the CPAP data import function). If ResMed's own clinical program can combine sessions and does not mess up the SpO2 data measured through its own module, we are talking about something thought about by ResMed in the first place, and somehow functionally copied to SleepyHead 1.0 and then lost with the 1.1 version. If the ResMed clinical system doesn't combine sessions, then the combining function was solely thought out by someone in the original group of developers of SleepyHead 1.0 and not a ResMed feature somehow lost developing Sleepy Head 1.1.

This is something someone using the ResMed clinical system would know about, provided the system has used data collected during day time sleep. I don't know if this does help narrowing down the area of programming structure, which was changed when the combine function was lost between SleepyHead 1.0 and 1.1, or not.

How ever, I also think somehow getting the combine function would back to Oscar would benefit many people, who for some reason have to sleep during day time. I also have a bad circadian rhythm problem, and have also other medical problems mandating day time sleep. As said before, people have to sleep during day time for various reasons, which enlarges the amount of people needing this function. For example many truck drivers suffering from sleep apnea are mandated to use a CPAP machine and supple data about their use including AHI and possibly also SpO2 data.

[biyahero]

One possible solution to the split sleep sessions might be to set your machine for a bogus time zone where noon in your actual time zone (where ResMed changes the day) is in the middle of your sleep period.

If you were to do that, the machine would not know when noon is in your time zone... for example if you were to set the machine for a time where it is six hours ahead of when noon is (ie 18:00 rather than 12:00) then the machine would interpret 
noon as being 18:00 and if you sleep in the day then the machine would not start a new sleep period until 18:00.

You can do this by entering the Clinical Menu and choosing to Erase all Settings, and probably best to start with a new blank SD Card from that point.  I have done this because most of the time I use my machine in a time zone that is 6 hours behind where the machine was issued, and it would always start a new sleep period at 06:00 (which was noon in where the machine came from), so if I got up at 07:00 the machine would show a sleep period of 1 hour.

I found that when you "Erase all Settings" it does not erase all the settings (but probably a good idea to write them all down just in case it did so that you could restore them in case it did), but what it does do is make it possible for you to set the time and date to whatever you want.

Having done that, now regardless of which of the two time zones I am using the machine, there are no split sleep periods.

Aside from that, my impression has been that even when my former machine did make split sleep periods, it seemed that when I took my SD card to my Sleep Doctor and she would check it using some ResMed software, the split sleep periods never seemed to be an issue, so maybe the ResMed software handles it differently the SleepyHead 1.1 or OSCAR?

[Blazing Black Beard]

One possible solution to the split sleep sessions might be to set your machine for a bogus time zone where noon in your actual time zone (where ResMed changes the day) is in the middle of your sleep period.

Whilst this might be a useful hack for people who work late or nights and people with regular sleep patterns, this isn't a solution for people with circadian rythm problems.

It has already been mentioned numerous times in this thread that because of major disruptions to circadian rythm, this hack would not be of any benefit and would be practically useless, as go to bed and wake up times are always changing.

[Crimson Nape]

Why can't you set the CPAP's clock to noon the first time you go to sleep for each day? That would only take about 30 seconds.