Interactive time line slide

[coldfeet7]

I have been very frustrated with how the Resmed AS10 doesn't seem to use the modem to access time on the cell tower, at least once a day, and sync the clock. It is a mystery and aggravation for me. My Wellue O2 Ring readily syncs to my PC time. As a result, keeping the two in sync is a challenge.

This graph shows the Resmed data and O2 ring data together (Viatom data import is a great feature of OSCAR). It appears the two sets of data (pulse, movement and SpO2 from the ring) are out of sync with the other data. I just now watched the two clocks tick over and the ring is ahead by about 1 second. So the PMO (pulse, movement and SpO2) should be pulled back by one second. (Admittedly, once second is not much off, but I have seen times when I have them off by 3-6 seconds or more. It just happens.)

   

I'd love to have an interactive feature in OSCAR to right-click, select "time shift" and then drag any one of the PMO graphs to better align with the event that was seen in the flow. OSCAR could then use that time-shift for the next night, unless corrected by the user for that night. These iterative corrections would allow each night to be properly aligned with its own time shift value, yet have the next night inherit that value since the drift from night to night is likely to be very little.

Since the AS10 is the one MOST likely to be off on its time, perhaps the above feature should be implemented on the flow rate chart? (I don't find the CPAP Clock Drift setting in Preferences to be intuitive. Is it applied to each new day and changing it doesn't affect previous days? Does this mean the drift value is inherited by each new day? Also, it isn't set when you are right there in the data and can judge the drift.)

I would guess the leak disturbance starting about 4:27:45 lead to the flow break, which lead to the movement, followed by the rise in pulse and then the drop in SpO2. (Since PMO all come from a single device, they are always in sync).

Thoughts? How do you deal with these time shifts?

[Neelix]

I just reset the time on the AirSense 10 each night before bed. I use the ViHealth app to sync the O2 ring to the phone, and then load a clock app with a second hand to set the time on the AirSense 10 to the second. That being said, the O2 Ring records events every 4 seconds, so if its only 1 second out I'd probably call that close enough. Also from what I've observed the inaccuracy of the clock in the AirSense 10 seems to be bad enough that by the end of a long session it's probably at least a couple of seconds out in comparison to when it started, so getting the two to correlate exactly over the course of a long session is going to be impossible. I think close enough is the best you can hope for really.

- Neelix

(Edit: That being said I do like the idea of being able to time-shift individual sessions in Oscar to facilitate corrections where needed.)
(Edit 2: See also this discussion: http://www.apneaboard.com/forums/Thread-...P02-levels )

[staceyburke]

On my Oscar there is an option that basically says that you started the Cpap and 02 recorded at the same time.

[Neelix]

Yeah but according to the text on the front page of the Oximeter Import Wizard, that's because the data from the CMS units has no time stamp information, so the only way to establish the timing is by having the user specify the start time. The Viatom data is time stamped and the importer for it doesn't have that option, you just select the file and it loads the data according to the time stamps.

[GuyScharf]

We understand the problem. I have logged this request in our OSCAR Issues log (Mantis #312), though it may already be in the list under a different description.

[coldfeet7]

Thanks for the link to the other discussion, Neelix. Crimson Nape made an interesting point that CPAP drifts during the night. That doesn't inspire <pun>   me with confidence in the design, but I guess they don't expect anyone to really study the data the way we do.

I would find resetting the time on the Resmed each night too tedious. You are more dedicated than I.

Too bad someone doesn't have a hack to the AS 10 firmware to have it check time and update it automatically. I wonder if the AS11 model does it?

[SarcasticDave94]

I doubt what you're after shows up on the 11 series. I don't think synchronizing various device clocks is on the manufacturers radar. The reasoning is simple. The PAP customer doesn't think it's necessary, and it has zero importance to consumer Jim Bob using his PAP enough to meet compliance. If compliance is met, there's not an issue according to the DME's.

To clarify, CPAP customers are named Rotech, Lincare, Apria, and so on. Otherwise called the DME's. You may have a ResMed 10 series, but ResMed didn't sell it to you, the DME did.

[Crimson Nape]

From what I understand, the AS11 is much harder to set the time. (Based on my understanding) You have to start from a factory reset to set the time.

[coldfeet7]

You are probably Dave. We are a SMALL minority. My Dr. is pleasantly surprised that I follow these things.

Not good to hear it is hard to set the time on the AS11....

My goal is to learn more about the relationships of movement, position, disturbance in breathing, heart rate, SpO2, etc. If they are in sync then I felt like I could more correctly make inferences about which came first, causation, etc.

[Neelix]

Al sorts of glitches for me last night.  my first CPAP session wasn't recorded to the SD card for some reason,  either was the event summary for the whole night.  (Oscar shows 0.0 but that doesn't match what the machine showed me this morning)

Also Daylight Savings started last night...  My O2 Ring apparently automatically adjusted the time between sessions... the AirSense 10 did not. 

-Neelix