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I didn't reverse-engineer the protocol for my blood pressure monitor in 24 hours

james.belchamber.com

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Re: I didn't reverse-engineer the protocol for my blood pressure monitor in 24 hours

#11

Post by lysace »

cestith wrote: post #2

Regarding white coat hypertension, the shot isn’t always necessary. Some people’s blood pressure just goes up from the stress of the clinical setting.

Taking a BP in person during a medical consultation, while stressed out because I know I have a very limited amount of time to do a verbal data dump of a large amount of information in a good way never fails to give me extreme values.

It also never helps to explain that this has happened many times before and that I have a reasonably high quality BP measurement device at home (most recently the exact same Braun model) that gives me decent measurements when I'm at rest/relaxed. They just look at me like I'm an idiot. How could a civilian conceivably perform such a complex measurement?

Then I get the predictably insanely high measurement and they look satisfied. Gotcha!

Please bring on the AI doctors.

Re: I didn't reverse-engineer the protocol for my blood pressure monitor in 24 hours

#12

Post by Arch-TK »

Would be fun to see the traffic dumps, I would love to try to figure out the protocol offline with them.

Just spent half a day reverse engineering a Windows virtual printer driver (for work) and had to force myself to stop spending the rest of the day doing it.

Re: I didn't reverse-engineer the protocol for my blood pressure monitor in 24 hours

#14

Post by llm_nerd »

SchemaLoad wrote: post #5
cestith wrote: post #2

Regarding white coat hypertension, the shot isn’t always necessary. Some people’s blood pressure just goes up from the stress of the clinical setting.

If you've got one of these machines at home it seems you really want to run it a couple of times. Often I find the first reading I get is quite alarming but then if I sit for a bit longer and run it another 1-2 times I get a very normal reading.

A big reason people's first measurement is often high is the positioning while putting the cuff on, adjusting to the pose, and then settling in place, a process which can spike pressure. Ideally you prepare yourself (cuff on, in place with your arms at rest, etc) and sit there and relax for five minutes before you take the first measurement, making it legitimately reflective of the at-rest state.

This often isn't possible, but it's a reason doctor visits usually drop you in a room by yourself with a machine that will take multiple measurements with a lengthy delay between. Though that's where the white coat thing comes into play and people are stressed about a doctor coming in, etc.

Re: I didn't reverse-engineer the protocol for my blood pressure monitor in 24 hours

#15

Post by kotaKat »

ck2 wrote: post #13

I have three blood pressure cuffs They all give me different numbers, by a lot sometimes btw you think they ever clean those devices? you think healthy people go to pharmacies? I won't even touch the signature pen, imagine what's on that

If you think that's bad, just think about what's in those finger-holes in bowling balls, between rounds of beer, bowling, and greasy bar food :)

Re: I didn't reverse-engineer the protocol for my blood pressure monitor in 24 hours

#16

Post by ErroneousBosh »

ck2 wrote: post #13

I have three blood pressure cuffs They all give me different numbers, by a lot sometimes btw you think they ever clean those devices? you think healthy people go to pharmacies? I won't even touch the signature pen, imagine what's on that

I had my blood pressure tested several times over the course of the month and each time it was high, weirdly high, like 160/100. If I drove in, weirdly high. If I cycled in, weirdly high. If I got another reading after sitting quietly in the waiting room reading my book for half an hour, weirdly high.

They wanted me to start on all sorts of medications immediately.

The second-last time, they got a reading of 220/130, and were going to get an ambulance to take me into hospital immediately.

Er, hang on a minute, folks.

That's beyond "hypertension crisis" and well into "incompatible with life" levels. That's the kind of pressure I see in hydraulic servo feedback channels, not living things.

They grudgingly agreed that someone with high blood pressure probably ought not to be making as much sense as I was, although what would I know about it, they're the professionals, etc etc.

The next time I noticed the automatic blood pressure cuff had a fresh new calibration sticker on it.

130/90. Not bad, for a reading taken at the doctor's surgery.

I wonder how many people are on medication they just plain don't need because of a plainly faulty sphyg though?

Re: I didn't reverse-engineer the protocol for my blood pressure monitor in 24 hours

#17

Post by alexfoo »

cestith wrote: post #2

Regarding white coat hypertension, the shot isn’t always necessary. Some people’s blood pressure just goes up from the stress of the clinical setting.

White coast hypertension isn't just about a clinical setting, it's more generally about the worry about the results of having your BP measured. [EDIT] OK, well maybe there's another type of hypertension which is related to anxiety about a high result regardless of the measurement setting.

I have to take daily BP measurements during titration for ADHD medication. (Using an _A&D UA-611 Plus_ machine at home.)

I can put the cuff on my arm and sit at my desk for 20 minutes to be nicely rested and calm, and then take 5 different measurements with a few minutes between each one. They'll vary quite wildly (anything from, say, 115/75 to 135/90) despite not moving between measurements or having any reason to be more or less agitated. I generally just ignore the low/high outliers and average the others. There's no pattern either, sometimes the outliers are first, sometimes last.

Also it's not just the monitor I have at home, the same is true of a probably more trustworthy machine in a clinical setting. I mentioned this to my doctor when I last visited and we saw the same thing with multiple measurements using a more sophisticated machine at the clinic.

Re: I didn't reverse-engineer the protocol for my blood pressure monitor in 24 hours

#18

Post by mh- »

alexfoo wrote: post #17
cestith wrote: post #2

Regarding white coat hypertension, the shot isn’t always necessary. Some people’s blood pressure just goes up from the stress of the clinical setting.

White coast hypertension isn't just about a clinical setting, it's more generally about the worry about the results of having your BP measured. [EDIT] OK, well maybe there's another type of hypertension which is related to anxiety about a high result regardless of the measurement setting. I have to take daily BP measurements during titration for ADHD medication. (Using an _A&D UA-611 Plus_ machine at home.) I can put…

I check my BP a lot for reasons, too, and this matches my experience as well. A few tips to reduce the variance (but it'll never go away):

* the position of both of your arms, and the angle your elbows are bent at matters. make sure the edge of your desk isn't pushing into your forearm.

* same goes for both of your legs. make sure you're sitting with legs uncrossed, relaxed angles, make sure the edge of your chair isn't pushing into the back of your thighs excessively.

* control your posture. slouching seems to have an effect too, but I'm unclear on the mechanism.

Anecdotally, the nurses at the doctor's offices I go to rarely (~never) bother to control for any of this other than telling me not to cross my legs. So while I fully believe white coat hypertension is a thing, I also think there's a lot of poor control of variables here. If you look up the AMA/AHA guidelines for blood pressure, the ranges they offer are predicated on some very prescriptive protocols for measurement.. which I virtually never see adhered to.

Re: I didn't reverse-engineer the protocol for my blood pressure monitor in 24 hours

#19

Post by pinkmuffinere »

> I tried feeding a lot of this into various Als (Kagi gives you access to a few with a nice interface) and I found that they mostly were stupid in ways that made me think

"stupid in ways that made me think" is (IMO) a really good summary of how AI is useful, as well as its pitfalls.

Re: I didn't reverse-engineer the protocol for my blood pressure monitor in 24 hours

#20

Post by gregdeon »

pavel_lishin wrote: post #3
cestith wrote: post #2

Regarding white coat hypertension, the shot isn’t always necessary. Some people’s blood pressure just goes up from the stress of the clinical setting.

I have an intense phobia of dentists; if I were wearing a constant monitor, I bet you could tell when I was at the dentist just by watching the blood pressure and heart rate spikes. (You'd have to find some way of differentiating them from me being in a car accident, or being attacked by a werewolf.)

I wonder if it would show up on the heart rate (or heart rate variability) tracking from an Apple Watch or similar. My Garmin picks up stressful events all the time.
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