(11-22-2018, 11:04 AM)Coffee Man Wrote: Has anyone used the Garmin Vivosmart 4 as an overnight pulse oximeter? It is an activity device, but apparently has the ability to record pulse ox throughout the night and the data can then be uploaded to a smartphone app. Since it is worn on the wrist, it seems less cumbersome than fingertip pulse oximeters. It is on sale on the Garmin website for $99.99.
I've got one. IMO it's not accurate enough to be useful for sleep apnea health tracking.
The Vivosmart 4's overnight sleep pulse ox recording only records once a minute, and only if you are still. It can't get a reading if you are moving in your sleep or if the band isn't tight enough. The results also depend on the snugness of the wristband, you'll get "higher" pulse ox readings if the band is tighter. And the overnight recording is limited to 4 continuous hours (I assume to save battery power). There is no option to record for a full night.
Because of the low sample rate, it's hard to tell when readings are anomalous (assuming that the device is normally accurate). If I had 60 samples a minute instead of one, and could zoom in on this dip, I'd have a better idea of what this reading meant, if anything, and I'd be able to synch it up with my CPAP data. As it is, I have no way to correlate this dip (if it's real) with my ResMed's flow - time graph, the data just isn't granular enough. Am I suppose to run to my doctor with this vague dip from my fitness tracker?
So, if you want a heart rate tracker and step counter, the Vivosmart 4 is super small and convenient. But if you want a recording pulse oximeter that will give you data that is actually useful, buy something else.
As for the Charge 3, no way to know if it is better or worse because the pulse ox hardware is there but they shipped without the feature. There is supposed to be a firmware update at some point to enable the pulse ox feature.
