[robbiep]

Now that would be a cool product. Lots of datapoints. I'm skeptical about the claim - yes, it's important, but there are so many variables that feed into it, and I need to be convinced that constant, 24 hr monitoring of BP would enable better management than spot tests, home BP management and the occasional 24 hr ambulatory monitoring.

It's a very consumer-targeted technology, although it would certainly find a place in emergency departments and ICUs. I am at a loss to think of ways as to how we would actually capture the data, although better minds than mine I hope come up with ways.

The problem is that to get a good read on arterial pressure you either need to do it the old fashioned way (occlude the artery and record that pressure, then slowly drop it until it's constantly flowing again - see [0]) - or you need to stick a cannula into an artery, as we do in ICUs, and measure pressure using a transducer.

Even technologies that stress their 'passivity' (see [1]) and try to capture this market use the old fashioned way. I don't see that changing anytime soon - you could try and somehow monitor the stretch of a small artery maybe using some variation of current o2 saturation sensors, coupled with advanced computer models of flow rate and variation in small arterioles, but that is a world away and would seem to me to be highly subject to variation/sensitivity.

My prediction is that this won't be possible until we are commonly implanting biometrics in people, but I guess we will wait and see!

[0] https://en.wikipedia.org/wiki/Korotkoff_sounds [1] http://www.visimobile.com/

[laarc]

It seemed promising to do some experiments with sewing a BP sleeve into a shirt, then setting up an Arduino to trigger it to inflate/deflate. It should be possible to record the result digitally. It'd be slightly uncomfortable, but even if it's only once per hour, it's still better than zero per hour. The noise would be annoying, but I have some ideas for how to make it quiet. But would anyone actually want such a thing?

Thanks for batting around the idea with me, and for the valuable references. I didn't know there was any other way to measure BP than the old-fashioned way.

[robbiep]

You're describing creating an ambulatory blood pressure cuff. I've had one attached to me and you get used to it fairly quickly, although it failed to measure blood pressure when I was active (I was cycling for a few of the readings, which you think would keep your arm fairly still and not cause a problem) Cool to make it yourself though! Have a look at these further links. The australian prescriber article you may find particuarly useful

http://www.racgp.org.au/download/documents/AFP/2011/November...

http://www.australianprescriber.com/magazine/20/1/18/20

https://en.wikipedia.org/wiki/Ambulatory_blood_pressure