Apple yesterday announced the Apple Watch Series 6 with a new sensor that enables blood oxygen monitoring capabilities, but Apple did not clarify which countries the feature would be available in.
Some health capabilities, like ECG and irregular heart rate notifications, have been limited in availability because of regulatory requirements, but it appears that those requirements don't apply to the blood oxygen monitoring feature.
According to the Apple Watch Feature Availability page, blood oxygen monitoring is available in more than 100 countries, suggesting there are no health-related regulatory issues that Apple has to overcome. A support document on using blood oxygen monitoring does mention that it's only available in "certain countries and regions," however, so there may be some omissions.
Those who are interested in purchasing an Apple Watch Series 6 specifically for the feature should double check the availability page to make sure blood oxygen monitoring is supported in their country.
Measuring blood oxygen with the Apple Watch Series 6 is done through the new Blood Oxygen app. It uses a series of red and green LEDs and infrared light to measure the amount of light reflected by the skin, with advanced algorithms using this data to calculate the color of the blood to derive the blood oxygen level. Bright red blood has more oxygen, while darker red blood has less.
The Apple Watch Series 6 is available for purchase from Apple's online store, with orders set to arrive starting this Friday.
Top Rated Comments
It will also be just as temperamental as the red (and infrared) LED is much more prone to interference. It's the reason why they will continue to use the green LED for plain pulse tracking - much more accurate & less susceptible to interference - particularly with exercise or any movement really.
So it will be:
- Green LED -> Exercising pulse rate*
- Red & Infrared -> Pulse Oximetry, foreground & background (+/- green LED to help lock onto the pulse rate**)
- Infrared -> background pulse rate reading when not moving*
* Just like all Apple Watches since day one.
** This is where Apple might be able to improve on existing tech
EDIT:
My money is on Apple introducing a Sleep Apnoea detection function next. The pieces of the puzzle are all there already:
- pulse oximetry
- movement detection
- noise detection
Disclosure: Anaesthesiologist
But even my colleague there simplifies it somewhat...
You can be hypoxic even if your pulse oximetry is normal and your Hb levels are normal.
How?
If a large proportion of your Hb is in a form that can't carry oxygen (eg. from carbon monoxide poisoning). However, if you ran a sample of the same blood through a laboratory *co-oximeter* it would show that your true saturations are in fact low.
Pulse oximeters measure functional oxygen saturation, ie. what percentage of Hb that can carry oxygen (ie functional Hb), is carrying oxygen. Even hospital pulse oximeters are limited in this way.
Laboratory co-oximeters measure fractional saturation, ie. what percentage of all Hb is carrying oxygen.
In short, if your Hb is normal (ie. you're not anaemic) and there is no chance there is a lot of abnormal Hb floating around (Met-Hb, Carboxy-Hb) then pulse oximetry is a good indicator of 'oxygen levels'.
None of this really matters to the user, but they really should rename 'Blood Oxygen Levels' to 'Pulse Oximetry'. It's correctly named in the 'Health' app.
If you were significantly anaemic you'd also have an abnormally increased heart rate so perhaps the Watch might pick up on that? I just feel sorry for all my US friends that have to pay lots of money to see a General Practitioner. We pay almost nothing here in Australia (but we do pay - happily - more tax for that benefit).
Anyway, it’s great this feature doesn’t have to go through regulatory approvals. But Apple talks about blood oxygen levels, not O2 sat. There (can be) a big difference.
This last part was also stated by the MD announcing the feature in the keynote, so I guess that’s how they get around regulation.