Fluctuating pulse

[ChicagoGranny]

CSV export:
Time, SpO2(%), Pulse Rate(bpm), Motion, SpO2 Reminder, PR Reminder
11:08:03PM Jun 3, 2022 96 56 0 0 0
11:08:07PM Jun 3, 2022 96 59 0 0 0

That file is from OSCAR. OSCAR only reads the bpm display, not each beat.

[Tec5]

CSV export:
Time, SpO2(%), Pulse Rate(bpm), Motion, SpO2 Reminder, PR Reminder
11:08:03PM Jun 3, 2022 96 56 0 0 0
11:08:07PM Jun 3, 2022 96 59 0 0 0

That file is from OSCAR. OSCAR only reads the bpm display, not each beat.

RadarRalf seems to suggest that this is the file that is sent to OSCAR from the O2 ring.

[ChicagoGranny]

RadarRalf seems to suggest that this is the file that is sent to OSCAR from the O2 ring.

Uh, no, this is what he said,

I think the data that is imported into OSCAR is 4 second intervals

Wellue O2 ring does not export information to OSCAR. OSCAR imports data from Wellue. What is in OSCAR is controlled by the OSCAR team, not by Wellue programmers.

Think about it logically, if Wellue only measures data every four seconds, it can't calculate BPM. It has to measure each beat.

Why don't you ask the OSCAR programmers ( viewtopic/t183702/OSCAR-v131-is-release ... -2022.html )? They would know what is in the Wellue data. Let us know what you learn.

[Rubicon]

I'm using a ResMed AirCurve 10 ASV machine... Getting really great numbers ...

ASV doesn't report how you're doing. It reports how it's doing.

You need to "deep dive" and look for Servo Attacks (which IMO is the cause of all the PC Events).

[Applecheeks]

Think about it logically, if Wellue only measures data every four seconds, it can't calculate BPM. It has to measure each beat.

Thinking about it logically… Wellue needs at least two beats and the time between those adjoining beats to calculate a pulse rate. To then report/display every four seconds would require averaging approximately 240 individual rates.

More likely the ring counts each beat over four second period, then calculates the rate from the count divided by 0.066 to give beats per minute.

Perhaps what you mean to say is that the O2 ring detects and counts each beat.

[RadarRalfs]

Wellue O2 ring does not export information to OSCAR. OSCAR imports data from Wellue. What is in OSCAR is controlled by the OSCAR team, not by Wellue programmers.

Why don't you ask the OSCAR programmers ( viewtopic/t183702/OSCAR-v131-is-release ... -2022.html )? They would know what is in the Wellue data. Let us know what you learn.

OSCAR imports the data from a binary file produced by the Wellue/Viatom products. See http://www.apneaboard.com/wiki/index.ph ... ile_Import
I expect the binary data has the same information as the CSV file mentioned earlier.

There is a lengthy and interesting discussion of the work that went into the OSCAR code here: http://www.apneaboard.com/forums/Thread ... r-importer

[ChicagoGranny]

Perhaps what you mean to say is that the O2 ring detects and counts each beat.

No, I meant to say it detects each beat because that is in the context of the discussion. If you want to expand the discussion, yes, it "counts" each beat.

To then report/display every four seconds would require averaging approximately 240 individual rates.

Huh?? 240 rates every four seconds?? You lost me.

[Chris33022]

Question on pulse rate reported by O2 ring. [...] I see that during the every night, especially for the first couple hours, my pulse rate changes a lot (as shown in the OSCAR report). Is this a normal thing

Hi Ropo. Thanks for posting this question! I, too, wear a Wellue 02 ring every night and I've been wondering the exact same thing. I also wear an Oura ring, which measures your HRV (Heart Rate Variability) every night. I developed a theory that might be totally off, but you never know. I noticed a possible parallel between nights when my Oura reports that I have high HRV and nights when my 02 ring reports that I have a high "Pulse Change".

When it comes to HRV, the higher the better. The older you get, the lower it gets. The fitter you are, the higher it gets (except for some exceptions when a high HRV can be a sign of illness--just as a low heart rate is usually a sign of health and fitness, but sometimes it's a sign of a problem). So if there is a connection between HRV and the 02 ring's "Pulse Change" number, then it may be a good thing that yours is high--it may be a sign that you're young, fit, and relaxed. It'll be interesting if you tell us you're actually old, unfit, and anxious.

Here's more info on HRV in case you don't know about it, from an article titled "Heart rate variability: How it might indicate well-being" (https://www.health.harvard.edu/blog/hea ... 7112212789 ):

<< HRV is simply a measure of the variation in time between each heartbeat. [...] Based on data gathered from many people, if the system is in more of a fight-or-flight mode, the variation between subsequent heartbeats tends to be lower. If the system is in more relaxed state, the variation between beats may be higher. This suggests some interesting possibilities. People who have a high HRV may have greater cardiovascular fitness and may be more resilient to stress. >>

And here's more info on HRV from Oura: https://ouraring.com/blog/what-is-heart ... riability/

Again, there is a good chance I may be totally off because HRV is a variation in milliseconds whereas the 02 ring's "Pulse Change" number seems to be much larger variations than mere milliseconds.

[Rubicon]

Not all HRV is good. AAMOF some can be outright bad. If we were to measure R-R variability (which is what we really need to measure) and example of bad becomes more apparent:



Looking at the ECG R-R channel in this example of an obstructive apnea patient, 2 types of HRVs can be seen. First, the small variations that correspond to respirations (HR increases during inspiration to deal with the surge of blood it sees)-- this is High Frequency (HF) phenomena; and second the more pronounced HRVs, which are of Low Frequency (LF), and correspond to respiratory events.

[Rubicon]

So HRV unto itself is good. It is the heart responding to something else (at least as it relates to sleep). There are 4 HRV bands, based on frequency. Let's divie them up into "good" and "bad":

• High Frequency (HF) (0.15 to 0.4 Hz) This wave would have a length of 2.5 - 6.7 seconds. In sleep, this activity will often translate into the phenomenon of Respiratory Sinus Arrhythmia (RSA), where the HRV would correlate directly with each respiration.
  
• Low Frequency (LF) (0.04-0.15 Hz) This wave would have a length of 6.7 - 25 seconds. In sleep, this activity will correlate with the respiratory events.
  
• Very Low Frequency (VLF) - 25 seconds - 5 minutes, vasomotor changes and thermoregulation.
• Ultra Low Frequency (ULF) - 5 minutes - 24 hours, circadian stuff.

[Rubicon]

But I think before further discussion about HRV ensues, it might be better to start with:

Is your EKG normal?

[Applecheeks]

Huh?? 240 rates every four seconds?? You lost me.

Yep, I don't know where the 240 measurement rates came from - (perhaps I was thinking about 60 bpm over 4 MIN interval) so ignore it- my bad.

Staying in the context of the "Fluctuating Pulse", what I think Tec5 was getting to was trying to understand is the granularity of pulse rates as reported by the Wellu O2.
By granularity i mean how often is the pulse rate reported out and what time interval is used to establish each pulse rate report.

If the pulse rate was calculated by the time interval between beats, the granularity would be very high (at maximum) and the pulse fluctuation would be also be high.
OTOH, if the pulse rate were calculated like most 30 sec EKG's are (count the number of beats and multiply by 2) then the beat-to-beat variability would be obscured.

For example, one of my family has occasional PVCs, and his EKG reports a 62 BPM, however in that same 30 EKG some beats are at a 120 BPM rate while others are at a 42 BPM level.

By a similar fashion, if the Wellue ring is detecting and calculating the pulse rate in 4 sec intervals, that would be more granular than an EKG (most of which detect and calculate in 30 second intervals). Greater granularity can well lead to greater (apparent) pulse fluctuations (the subject of the thread).

So, it is probably useful to know for sure the details on how Wellu calculates pulse rates and the interval used for each data point. ( my suspicion is 4 seconds - but that actually seems like overkill)

[Chris33022]

So, it is probably useful to know for sure the details on how Wellu calculates pulse rates and the interval used for each data point. ( my suspicion is 4 seconds - but that actually seems like overkill)

Is the following helpful, by any chance?

I just Googled: wellue o2 measures pulse every how often

And I found this for the Wellue O2 Ring:

<< Measurement interval: 1 second (in-app intervals 4secs) >>

At this link: https://sleepgadgets.io/review-wellue-o2ring/

And this on the Wellue website:

<< Accurate ring oxygen monitor, tracks your blood oxygen level, heart rate, and body movements every second automatically.
Print and share four-second interval, high-resolution oximetry reports.>>

At this link: https://getwellue.com/products/o2ring-w ... e-oximeter

[dataq1]

But I think before further discussion about HRV ensues, it might be better to start with:

Is your EKG normal?

I read your citation from Harvard, and while interesting, it seems replete with "may", "might" "possible-type terms that doesn't instill confidence in the assertions. That Harvard piece, written 6 months ago, makes it plain that researchers are just "exploring" HRV.

The Oura citation seems to amplify the possibilities that the Harvard citation speculates (however, I tend to regard the projections made by the manufacturers as wishful marketing).

So I agree that further discussion about HRV ought to be held off for now. Perhaps it deserves it own topic.

[Chris33022]

I read your citation from Harvard, and while interesting, it seems replete with "may", "might" "possible-type terms that doesn't instill confidence in the assertions. That Harvard piece, written 6 months ago, makes it plain that researchers are just "exploring" HRV.

The Oura citation seems to amplify the possibilities that the Harvard citation speculates (however, I tend to regard the projections made by the manufacturers as wishful marketing).

So I agree that further discussion about HRV ought to be held off for now. Perhaps it deserves it own topic.

Hi dataq1. I'm the one who posted the Harvard and Oura citations. I agree the "may", "might", etc were less-than-ideal, but it was a quick search, and in fact I was surprised at the tentativeness of that piece because when I got the Oura ring a few months ago I spent a long time researching HRV, and the stuff I read about it at the time was not tentative at all; it was written about in a much more definite manner in lots of reliable sources--unless my memory is playing tricks on me, which is totally possible, and if that's the case, I'm sorry. Unfortunately I don't have time to go back now and try to find all those sources that I think I saw before. But they should be easy to find by Googling--if I'm not misremembering.