CMS50F v6.1 time problem in OSCAR

[dcuste]

I'm now running OSCAR 1.1.1 but have had this same problem in the earlier releases of OSCAR too. 

I have the time set to within a minute in both my AiriSense10 and my CMS50F. When I go to bed, I start recording on the CMS50F and breathing with the AirSense10 within a few seconds of each other. In the morning, the AirSense10 data imports into OSCAR and the start and end times are correct and I can see the initial pressure ramp. When I import the CMS50F and select it to use the AirSense10 start time, the resulting traces start in sync, but by the end of the sleep cycle the CMS50 data goes about 10 minutes past the actual end time. 

In the middle of the session last night, I got up for 5 minutes, which stopped my AirSense session, and I pulled my finger out of the CMS50F. Sure enough, when I downloaded all the data in sync with the beginning, the time of the middle of the night break in AirSense session and the CMS50F loss of pulse gap was off by 10 minutes. 

It seems like the CMS50F adds and extra 10 minutes of data before it actually is even turned on record, but I can't even imagine how that could happen.

What am I doing wrong?

[Jeff8356]

I noticed there is always a discrepancy in the times between the two.  Even gone so far as to carefully document the start and end times of both using my phones clock.  The CMS50F was always longer than the xPAP.  Whatever they use to keep time in the 50F seems to speed up through the night.  There is nothing we can do but compensate for it.

I got into the habit of turning off the 50F as soon as I awaken.  I leave my xPAP attached and running for few more minutes, as long as it takes me to get untangled, stretch and get out of bed.  Then shut off my xPAP.  That usually narrows it down to <2 minutes, sometimes the timing lines up just right.

[GuyScharf]

Are you importing to OSCAR directly from your CMS50F by cable? There is a known error in the oximeter importer that results in extra data being "imported." The workaround is to use the SpO2 Assistant to read the data and place it in a data file. Then import the data file into OSCAR. This import appears accurate.

In my case, when I looked at the directly imported SpO2 chart, I could see a repetitive pattern in the first 10 minutes that indicated duplicated data. The duplicate data is not limited just to the beginning of the file. I had one case where the SpO2 file was at least 30 minutes longer than it should have been.