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Commonly used arm positions can overestimate blood pressure readings: study

(medicalxpress.com)
330 points wglb | 1 comments | 14 Oct 24 17:57 UTC | HN request time: 0.201s | source
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swores ◴[14 Oct 24 19:31 UTC] No.41841008[source]▶
I've never looked into research on this subject, but I always assumed this was already well established and known - and it was definitely somewhat already either known or at least believed to be the case:

- Every doctor in the UK I've ever seen do a BP test has made sure the patient's arm is in the right position, rested on a table/cushion if needed, in a way that matches the findings in this study (and while I've only needed my own BP tested once or twice, I've sat in on many, many doctors while they tested the BP of family members of mine).

- My home BP device is a Braun wrist cuff (and is at least a few years old), which has a built in feature that uses an accelerometer to guide you to raise your arm until it's at an angle which means your wrist is at the same level as your heart (this one: https://www.cora.health/guide/best-blood-pressure-monitor/#1... )

replies(2): >>41841172 #>>41848454 #
tocs3 ◴[14 Oct 24 19:49 UTC] No.41841172[source]▶
Can you trick the Braun device into thinking your wrist is level with you heart?
replies(1): >>41841246 #
1. swores ◴[14 Oct 24 19:56 UTC] No.41841246[source]▶
Yes - it's just a digital spirit level of sorts, that instead of being calibrated to align with the ground is calibrated such that, based on typical angles and dimensions of a human body leads to the wearer holding their arm up in front of them with the device in line with the heart.

Here's what it looks like, the device won't start until you've got the ball to hover in the middle circle, but it has no way of knowing if you're doing it properly or if you're lying down or leaning your body forwards or whatever else would mean that the angles no longer put it level with your heart.

https://imgur.com/a/pV6xcpc

edit to add: so when used correctly it looks roughly like this - https://m.media-amazon.com/images/S/aplus-media/vc/573a171a-...

Basically the same logic as, for traditional upper arm cuff devices, giving the instruction to rest your arm on something next to you that allows your forearm to be resting both comfortably and straight, parallel to the floor - which again, doesn't technically mean the middle of your upper arm must be level with your heart, but since nobody would really be comfortable putting their forearm flat on a low down coffee table or a high up standing desk it works as a proxy that's simpler than asking people to think about lining anything up with their internal organs.