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Prior to releasing ECG functionality in the Apple Watch Series 4, Apple needed FDA approval for the feature, but the same isn't true of Blood Oxygen monitoring in the Apple Watch Series 6 because Apple doesn't see it as a medical feature.

1blood-oxygen-app.jpg

As outlined by The Verge, pulse oximeters like the blood oxygen tracking feature in the Apple Watch are considered Class II Medical devices and documentation is generally required, but there's a way around that. If a pulse oximeter is marketed as being for general wellness or fun rather than for a medical purpose, FDA documentation is not required.

That's the reason why the blood oxygen tracking feature is not being marketed by Apple as a medical feature, and an Apple Support document clearly states that measurements taken using blood oxygen tracking are "not intended for medical use" and are designed for "general fitness and wellness purposes."

The Apple Watch Series 6 Blood Oxygen app provides no insight into blood oxygen readings, nor does it send alerts when a lower than normal blood oxygen level is detected, because that would be a medical feature.

Apple is prohibited from using the blood oxygen tracking feature from impacting the medical care that someone receives, which is a deviation from how the ECG functionality works. ECG readings from the watch are used to alert users of an abnormal heart rhythm (atrial fibrillation) and thus required greater oversight. Apple was required to provide the FDA with data proving that the feature can detect atrial fibrillation, which could be examined by experts.

Avoiding regulatory approval in the United States and in other countries permitted Apple to launch the blood oxygen feature in more than 100 countries. ECG availability is still limited because it requires medical approval in each country it launches in.

bloodoxygenprocess.jpg

Michael Matheny, co-director of the Center for Improving the Public's Health through Informatics at Vanderbilt University, told The Verge that when he went to find data on how well the pulse oximeter in the Apple Watch works, there wasn't much out there. "It was concerning to me," he said.

It's also potentially confusing to customers because Apple's marketing is sometimes unclear. "Patients and consumers don't really understand the difference," said Matheny. "So they'll start using the device and relying on the information."

There have been multiple reports from Apple Watch Series 6 owners suggesting the blood oxygen tracking feature isn't particularly accurate when compared to a finger worn pulse oximeter, with successive readings that can be all over the place.

We here at MacRumors have also noticed problems with unusual readings that don't seem to be right and that are suggestive of breathing problems when there are none, which is potentially problematic and could lead to panic over nothing. The feature can also be hard to use, requiring little arm movement with results potentially impacted by cold weather, tattoos, and other factors. Some users have no problem, though, and all Apple Watch Series 6 owners should remember that blood oxygen tracking isn't a medical feature and should not be relied on as a measurement of health, even if it may have some utility as an alert in an emergency situation.

Article Link: Why Apple Didn't Need FDA Approval for the Blood Oxygen Tracking Feature in the Apple Watch Series 6
 
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sparkinstx

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Nov 1, 2017
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So just call it a gimmick, and you're good? If you're sick with COVID, and worried about your breathing, I could see O2 Sats monitoring as a medical feature. Jus' sayin'.
 
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Metrosey

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Oct 18, 2019
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Apple was smart to do this. Maybe down the line they will see FDA approval.

I compared my watch pulse ox to a medical fda proved device yesterday, and each time, there was only a 1% differential between the watch and the device.

Doubtful at this rate. It isn’t even accurate currently.
 
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Prof.

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Apple was smart to do this. Maybe down the line they will see FDA approval.

I compared my watch pulse ox to a medical fda proved device yesterday, and each time, there was only a 1% differential between the watch and the device.
I checked it with the monitors in the emergency department where I work, and it was between 1-3% different each time.

Now, 3% is a big difference. We like you to be 95-100%, but darn near 100% if you're young and healthy. I'm going to be 32 and my normal is 97%

SOME suggest no higher than 99%, since the max is 100%. What if you're more than 100%? Oxygen toxicity?!

edit to add clarification: the monitor does not read above 100%, so if you're reading at 100%, are you really 100? or are you 101? 103? Hence, keep it at 99%
 
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Stevez67

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Dec 24, 2016
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The ECG app doesn't diagnose heart attacks, per all the warnings that show up when you start using it. But the health apps, and the information they provide, are a good way to keep track of your personal "normal" and get a warning if something begins to go haywire.
 
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longofest

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Apple was smart to do this. Maybe down the line they will see FDA approval.

I kind of hope they go this route, and it would be a smart play. They release it now as a general wellness accessory, and behind the scenes work with FDA and other regulatory regs to get approval for health benefits. If it passes, Apple provides software update that allows notification of low blood oxygen in approved countries.

I doubt they will do this because it would cost $$$ to do that and chief bean counters wouldn't see the reason to do that. But especially in a COVID world, getting notified of low spo2 would be hugely beneficial.
 
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Prof.

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The ECG app doesn't diagnose heart attacks, per all the warnings that show up when you start using it. But the health apps, and the information they provide, are a good way to keep track of your personal "normal" and get a warning if something begins to go haywire.
Correctomundo.

I work up last year with two alerts that I had an abnormal rhythm... prob a dream or something.
 
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Apple_Robert

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I checked it with the monitors in the emergency department where I work, and it was between 1-3% different each time.

Now, 3% is a big difference. We like you to be 95-100%, but darn near 100% if you're young and healthy. I'm going to be 32 and my normal is 97%

SOME suggest no higher than 99%, since the max is 100%. What if you're more than 100%? Oxygen toxicity?!
I am older than you and my average is 98%. From my experience with the watch since 9.21, it has been consistent with its background readings as well as the manual test.

I like that I can track long term results with the watch and compare to the FDA device when I want. Doing this will give me and my doctor a good overview of my day to day health. I also log my BP twice daily, along with keeping tracking of food intake, sleep, and bowel movements every day.
 
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hlfway2anywhere

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Jul 15, 2006
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So just call it a gimmick, and you're good? If you're sick with COVID, and worried about your breathing, I could see O2 Sats monitoring as a medical feature. Jus' sayin'.
Not calling it a medical device eliminates their liability when you choose to use it in critical situations and it fails to provide medically accurate data. It doesn’t mean it’s not technically medical data.
 
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Apple_Robert

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I kind of hope they go this route, and it would be a smart play. They release it now as a general wellness accessory, and behind the scenes work with FDA and other regulatory regs to get approval for health benefits. If it passes, Apple provides software update that allows notification of low blood oxygen in approved countries.

I doubt they will do this because it would cost $$$ to do that and chief bean counters wouldn't see the reason to do that. But especially in a COVID world, getting notified of low spo2 would be hugely beneficial.
It would be a huge cost upfront. However, if Apple could get it done and it be better than the competition, it may help drive more watch sales.
 
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Apple_Robert

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Spend a grand on a new watch for a feature thats more accurate on a 15 buck device from amazon.
Sure. Sign me up and take my money!
You can get the watch for $400 dollars. The watch nerds on here (like me) know what we bought with the series 6. If Apple had marketed it as medically accurate, your post would have marginal merit.
 
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terraphantm

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The ECG app doesn't diagnose heart attacks, per all the warnings that show up when you start using it. But the health apps, and the information they provide, are a good way to keep track of your personal "normal" and get a warning if something begins to go haywire.
The ECG physically can't diagnose heart attacks because you're not getting a full picture. Take a look at this 12-lead of a STEMI

ECG-Anterior-inferior-STEMI.jpg


This guy is having an anterior and probably inferior STEMI based on leads V1-V5 as well is II/III/AVF. But lead I, which is equivalent to the lead your Apple watch checks, is pretty much normal. The Apple watch would have totally missed it, which is why they warn you every time that it cannot diagnose a heart attack.

It is useful for detecting afib, since that shows up in all leads. And it could probably also be useful for detecting things like heart block or QT prolongation and various other arrhythmias, but Apple decided to focus on afib.
 
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deeddawg

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Jun 14, 2010
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Spend a grand on a new watch for a feature thats more accurate on a 15 buck device from amazon.
Sure. Sign me up and take my money!

What a silly, hyperbolic statement.

Nobody's spending $1000 on an Apple Watch just for the blood oxygen feature.... :rolleyes:
Can't even get near that price without up-featuring the watch or band choice substantially.

Did you have something to actually contribute?

My guess is Apple eschewed any FDA certifications so they could get the device out widely and quickly. If they feel there's value in gaining approvals from the FDA (and equivalent authorities in other nations) they will do so in the future. Or may already be pursuing such.

For now I'd consider it a curiosity and stick with a medical device as suggested by one's doctor. The watch may perhaps provide a prompt for someone to take a reading with their medically-certified device, or may serve other trend measurement type purposes for medical professionals with patients in treatment. Even some amount of individual-reading inaccuracy is inherently smoothed when looking at a sufficiently long trend.

Should I find myself in a position in which my blood oxygen becomes more than a curiosity, I'll go by what my doctor says rather than folks on an Internet forum. :p
 
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69Mustang

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I kind of hope they go this route, and it would be a smart play. They release it now as a general wellness accessory, and behind the scenes work with FDA and other regulatory regs to get approval for health benefits. If it passes, Apple provides software update that allows notification of low blood oxygen in approved countries.

I doubt they will do this because it would cost $$$ to do that and chief bean counters wouldn't see the reason to do that. But especially in a COVID world, getting notified of low spo2 would be hugely beneficial.
I doubt they'd go this route. The wrist is not a good place to get a consistent and accurate reading. Fingers, earlobes, toes, yes. Wrist, not so much. As you mention, the cost would be high. Also, it would mean an increase in liability. Being certified as a medical device for blood oxygen tracking isn't going to sell any more AW's than the ECG's FDA certification did.

It would seem like a heck of a large expense in time, money, and risk for not that great of a benefit.
 
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