Discrepancy with desaturation events between Sleepyhead and Oximeter software

[Asjb]

Hello, can anyone help please?

I am getting wildly different results for <total desaturation events> and I can't work out what is going on.

I use a Contec CMS 50F oxymeter and import the night's data into the software that comes with the oxymeter, <SpO2 Assistant>, then print out the <oxymeter report>.

I also import the oxymeter data each morning into Sleepyhead.

I have set both programmes to the same definition of a desat event i.e. <drop in SpO2 by at least 4% for a minimum duration of 10 seconds>

But the programmes are reporting hugely different numbers of events e.g. last night Sleepyhead tells me I had 198 events in total, and SpO2 assistant tells me I had 15 events in total. I would judge the O2 graph suggests that 198 is the more accurate.

My cardio is keen that desat events are minimal (to avoid sympathetic nervous system stimulation of the cardiovascular system).

Does anyone have any ideas please about what might be going on with the software?

Thanks

Best regards

[Crimson Nape]

Are the desaturation thresholds in both programs set to the same values? That is about the only thing I can think of.

Parameter adjustment can be found in the SpO₂ program under: Options->Parameter Analysis menu.

SleepyHead has it under: File->Preferences->Oximetry tab.

[Asjb]

Are the desaturation thresholds in both programs set to the same values? That is about the only thing I can think of.

Yes, thanks, both set to the same. I mentioned above
<I have set both programmes to the same definition of a desat event i.e. <drop in SpO2 by at least 4% for a minimum duration of 10 seconds> .

[THEVGE]

I found this old thread as I ran into the same issue with my Beurer PO80 pulse oximeter (a re-branded Contec CMS50).

With same analysis parameters for SpO2 (4 % drop for 10 (s)) I get 18 (Beurer) vs 156 (Oscar) events.
With same analysis parameters for PR/PC (6 bpm for 8 (s)) I get 30 (Beurer) vs 29 (Oscar) events.

I did a quick check and concluded it seems Oscar is flagging incorrectly. Attached a random SpO2 part of my night, showing SpO2 scale from 93 % to 98 %. You can see the per 1 (s) measurement (which is the measurement frequency of the oximeter), you can see there are 0 drops/increases of 4 % yet Oscar flags 6 events.