Pulse Change Index

[Thumper1947]

If you connect pulse oximetry data to Oscar, on the statistics page there is a category called, "Pulse Change Index." It calculates a rating for the night. Does anyone know what this means, what is normal, how to use it, and where you can find any information on it. I have googled it and went to Wikipedia to no avail. Thanks.
Thumper

[Pugsy]

It just means how many times the pulse rate has changed, within whatever parameters it has been set to reflect a change, during the night on average per hour throughout the night.

Our pulse rates change throughout the night normally and will vary for any number of reasons.
If O2 levels drop there is normally a corresponding increase in pulse rate. That is probably the most important association.

When it comes to oxygen drop index...I think the parameters are probably 3 to 4 percent so there is a desat index.

I do not know what parameters might be set for a pulse rate index for how many changes happen during the night. That should be somewhere in the pulse oximeter paperwork or settings where a person can customize the reporting.

[rick blaine]

Hi Thumper1497,

They may have had in mind heart rate variability, which is defined as "the measurement of the autonomic nervous system (ANS) that is largely believed to be one of the finest objective metrics for physical strength and determine the body’s readiness to perform any action."

For more, see here:

https://bestdoctor.com/blog/heart-rate- ... mal-range/

[Thumper1947]

Thanks Pugsy and Rick. I'm going to try and figure this out, but I'm not sure that it's useful information that I can use to improve my sleep.
Thumper

[RadarRalfs]

Hello,

I am curious about this also. As far as I can tell from the OSCAR Preferences Oximetry tab, a Pulse Change event is when your heart rate changes by more than 5 beats per minute, for a duration of at least 8 seconds. The Index is how many times per hour this occurs. I have searched but can find no explanation of what is considered good, bad or normal. The OSCAR Statistics page shows my average between 7 and 8. Recently, during an atrial fibrillation event, the Index registered 207 for that day.

I know this is an older thread but it would be interesting to better understand this topic and to compare numbers with others.

Regards,
Dave Hutchinson

[dataq1]

This is a subject that I have some interest in as well. But before exploring the pulse rate change index (and the criteria to flag a "change" in pulse rate as a change). I'd like to better understand how oximeters (particularly Ring) determine pulse rate.
Theoretically a pulse rate could be calculated by the time two between two consecutive QRS complex (generally about 1 sec), alternatively it could be calculated by the time over 60 beats, or more practically the number of QRS over a timed period (usually 30 seconds or 60 seconds).
What I don't know (because I don't have a ring or access to information on the ring) is how often the pulse rate is updated and reported out.

MY experience with fitbit watches, would seem to indicate that the pulse rate is updated and flashed to the watch face every few seconds (but I have no idea how long the "look back period" might be). However when the pulse rate data is transmitted to the fitbit app, the pulse rate data is averaged over a 5 minute period and then plotted (there is no option to select a higher resolution).

So, getting back to the ring oximeter data transmitted to OSCAR.... how many data points are presented per hour on Oscar's report of pulse rate from a ring oximeter? Anyone know?

[Julie]

DataQ - start your own thread - you're hijacking someoe else's!

[Tec5]

@julie,
I am also interested in both - how pulse rate is determined and the parameters for indexing change events. Because they are so closely related there’s no reason why those can’t be discussed together.
IMO, that’s not derailing at all. But it’s really Pugsy’s call.

[Pugsy]

As far as I am concerned similar topics and no harm in putting the new questions (which are along the same line as the original post) in this thread.
Originally brought back to life by RadarRalfs and not dataq1 and RadarRalfs was a new account first post and I obviously approved it without asking for a new or separate thread.

Now someone else might feel differently and they are of course allowed to feel that way and voice their feelings.

What I don't like is when people divert to comments about posts and snarky snide remarks take over any thread.

Keep it polite and play nice folks.

[Thumper1947]

Tech & DataQ,
There were a couple of links that I tried while trying to find out some more information. They may or may not provide some useful information to you, but here they are. So far I haven't been able to find out the frequency of the sensing.

https://blog.getwellue.com/apple-watch- ... -readings/

https://www.google.com/search?client=fi ... ue+o2+ring
Thumper

[ChicagoGranny]

Hi Thumper1497,

They may have had in mind heart rate variability, which is defined as "the measurement of the autonomic nervous system (ANS) that is largely believed to be one of the finest objective metrics for physical strength and determine the body’s readiness to perform any action."

For more, see here:

https://bestdoctor.com/blog/heart-rate- ... mal-range/

Sudheendra is a passionate blogger for 8 years and holds a Degree in Journalism & Mass Communications.

I tend not to trust health journalists who don't have a medical background.

[RadarRalfs]

Dataq1 wrote: "how many data points are presented per hour on Oscar's report of pulse rate from a ring oximeter?"

The O2Ring is what I use. Their website website ( https://getwellue.com/pages/o2ring-oxygen-monitor) states:
MEASURE INTERVAL: 1S
DISPLAY INTERVAL IN APP DATA CHART: 4S

I think the data that is imported into OSCAR is 4 second intervals - at least that is what is generated with a 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

[dataq1]

Thanks Radar,
That CSV table is most useful, and it provides a big clue as to where to find information on the pulse rate change calculation.

If the CSV you captioned is the only O2 ring data stream sent to the OSCAR program, then the calculation of pulse rate changes must be being performed by the OSCAR program.

It seems like the resident experts (those that developed OSCAR and it's updates from Sleepyhead seem to hangout at the apneaboard forum. I'd suggest that @Thumper 1947 inquire there to "talk" with the program developers about the algorithm they are applying to calculate the pulse rate deltas.

Now, I'm a bit surprised that Wellvue says the "measurement interval" is 1 second. For example, with a typical ECG the measurement interval for pulse rate is 20-30 seconds. OTOH, I'm assuming that their understanding of measurement interval is the observation interval that is used to measure (calculate) the pulse rate, perhaps they have a different meaning.