BP Measuring Equipment Part 2 (still a bit OT ..!)

[Arfa Daily]

Following on from the discussions we had last week about how these things
work, this morning I bought one of the arm cuffs from Lloyds. The air tube
is a little larger bore than that on the wrist cuff that originally came
with my measurement unit, so the plug-in bit of the tube didn't immediately
fit. I solved that by taking the plug-in from the wrist cuff, upping it's
diameter a bit with some tape, and then inserting it into the end of the new
arm cuff air tube.

When I tried the unit out, it pumped up the cuff to the correct level, as
indicated by the true pressure reading on the display, and by judgement,
comparing how tightly it 'strangled' my arm against how much the one at my
doctor's does.

As soon as it went into the auto deflation phase, it started to pick up
pulse, so I figured that it could still sense the minute variations in air
pressure in the tube, caused by the vein pulsing inside the cuff. The final
reading that it gave was very sensible at 130 / 85, so it would seem that as
we guessed, the measurement principle is effectively 'decoupled' from
whatever type of cuff is providing the input to the pressure sensor.

I will continue to use it on this basis for the next couple of weeks until
my next 'genuine' assessment is due when, if it has continued to look like
it's giving reasonable results, I will take it along with me, and do a
direct comparison with the nurse's machine.

Arfa

 

[GregS]

Following on from the discussions we had last week about how these things
work, this morning I bought one of the arm cuffs from Lloyds. The air tube
is a little larger bore than that on the wrist cuff that originally came
with my measurement unit, so the plug-in bit of the tube didn't immediately
fit. I solved that by taking the plug-in from the wrist cuff, upping it's
diameter a bit with some tape, and then inserting it into the end of the new
arm cuff air tube.

When I tried the unit out, it pumped up the cuff to the correct level, as
indicated by the true pressure reading on the display, and by judgement,
comparing how tightly it 'strangled' my arm against how much the one at my
doctor's does.

As soon as it went into the auto deflation phase, it started to pick up
pulse, so I figured that it could still sense the minute variations in air
pressure in the tube, caused by the vein pulsing inside the cuff. The final
reading that it gave was very sensible at 130 / 85, so it would seem that as
we guessed, the measurement principle is effectively 'decoupled' from
whatever type of cuff is providing the input to the pressure sensor.

I will continue to use it on this basis for the next couple of weeks until
my next 'genuine' assessment is due when, if it has continued to look like
it's giving reasonable results, I will take it along with me, and do a
direct comparison with the nurse's machine.

I bought a bunch of vitamins and stuff last week. I took all these blood pressure
relieving remidies and the next day my pressure shot up over 150
and I felt like I was on steroids. One of the pills was responsable
but have not yet tracked it down. I can suggest trying
L-Theanine.

greg

 

[Charlie]

Following on from the discussions we had last week about how these things
work, this morning I bought one of the arm cuffs from Lloyds. The air tube
is a little larger bore than that on the wrist cuff that originally came
with my measurement unit, so the plug-in bit of the tube didn't
immediately fit. I solved that by taking the plug-in from the wrist cuff,
upping it's diameter a bit with some tape, and then inserting it into the
end of the new arm cuff air tube.

When I tried the unit out, it pumped up the cuff to the correct level, as
indicated by the true pressure reading on the display, and by judgement,
comparing how tightly it 'strangled' my arm against how much the one at my
doctor's does.

As soon as it went into the auto deflation phase, it started to pick up
pulse, so I figured that it could still sense the minute variations in air
pressure in the tube, caused by the vein pulsing inside the cuff. The
final reading that it gave was very sensible at 130 / 85, so it would seem
that as we guessed, the measurement principle is effectively 'decoupled'
from whatever type of cuff is providing the input to the pressure sensor.

I will continue to use it on this basis for the next couple of weeks until
my next 'genuine' assessment is due when, if it has continued to look like
it's giving reasonable results, I will take it along with me, and do a
direct comparison with the nurse's machine.

Arfa

All this has got me wondering what these DIY BP machines are doing and how
well they do it.
The instruction booklet for mine tells me that it uses the oscillometric
method and uses fuzy logic intelligence to sense the values.
That's a big help isn't it?
Now what does that mean and how does it relate to the professional way.
Onward to Google where we find this link :
http://www.freepatentsonline.com/7014611.html.
Again Google to the rescue with http://www.ncbi.nlm.nih.gov/pubmed/11518839
and then http://www.microlifeusa.com/pdfs/bp/is_mam_accurate.pdf.
What I really know is if my spouise and I go out for dinner I do NOT check
my BP the next morning. Talk about sodium sensitivity, whew!
Try to digest the articles and then at your next visit to the folks with the
mercury column see if they are following the testing protocol.
Try out some of the new words.
BTW, I did not delve into the finer points of fuzzy logic but then again it
seems that most of my logic is fuzzy anyway.

Charlie ( I think I will rest for a while)

 

[GregS]

All this has got me wondering what these DIY BP machines are doing and how
well they do it.
The instruction booklet for mine tells me that it uses the oscillometric
method and uses fuzy logic intelligence to sense the values.
That's a big help isn't it?
Now what does that mean and how does it relate to the professional way.
Onward to Google where we find this link :
http://www.freepatentsonline.com/7014611.html.
Again Google to the rescue with http://www.ncbi.nlm.nih.gov/pubmed/11518839
and then http://www.microlifeusa.com/pdfs/bp/is_mam_accurate.pdf.
What I really know is if my spouise and I go out for dinner I do NOT check
my BP the next morning. Talk about sodium sensitivity, whew!
Try to digest the articles and then at your next visit to the folks with the
mercury column see if they are following the testing protocol.
Try out some of the new words.
BTW, I did not delve into the finer points of fuzzy logic but then again it
seems that most of my logic is fuzzy anyway.

Charlie ( I think I will rest for a while)

My first maching used a microphone. It was basically exactly like a manual setup
except with pump and a mic replacing the diaphram. You might be able to detect the
pulses through the air pressure in stead of a mic.

Fuzzy logic should probably be fuzzy control. Adjusting parameters of the system
I think of it as a loop withinn a loop.

I have a lot of troubles with my manual cuff, where the diaphram is sewn in
on the strap. The diaphram stretched out and was usually hanging too
far out. I took it off and put it where I want.

greg

 

[Arfa Daily]

All this has got me wondering what these DIY BP machines are doing and how
well they do it.
The instruction booklet for mine tells me that it uses the oscillometric
method and uses fuzy logic intelligence to sense the values.
That's a big help isn't it?
Now what does that mean and how does it relate to the professional way.
Onward to Google where we find this link :
http://www.freepatentsonline.com/7014611.html.
Again Google to the rescue with
http://www.ncbi.nlm.nih.gov/pubmed/11518839 and then
http://www.microlifeusa.com/pdfs/bp/is_mam_accurate.pdf.
What I really know is if my spouise and I go out for dinner I do NOT check
my BP the next morning. Talk about sodium sensitivity, whew!
Try to digest the articles and then at your next visit to the folks with
the mercury column see if they are following the testing protocol.
Try out some of the new words.
BTW, I did not delve into the finer points of fuzzy logic but then again
it seems that most of my logic is fuzzy anyway.

Charlie ( I think I will rest for a while)

Thanks for the links Charlie. I will follow up on them tomorow. As far as
the 'DIY' method relating to the professional method, they are one and the
same these days. The doctors' surgeries now use automatic electronic units
made by the same people as the DIY ones, rather than mercury-column
sphygmos. There seems to be two fundamental 'qualities' of DIY units - those
that are "Clinically Certified for Accuracy", and those that aren't.

Fuzzy logic is interesting stuff. All washing machines use it now, for
instance. The logic is able to make 'decisions' based on all sorts of
analogue input parameters, to modify the washing times and so on.

Arfa