reliable metre readings

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youone DAFNE Graduate
Hull and East Riding Diabetes Network
102 posts

I've been closely watching my metre readings on my omnipod, since the pod is very accurate in what it does a unreliable reading can cause issues,
Over my life with type 1 I got into the routine of using more than 1 metre,1 for the car and the other for general readings.
Since taking the omnipod ( which is fantastic) its technology is up to what I need, but it begs the question is the metre,
I'm having doubts before Christmas I had a reading of 17.1 after four hours ,yet from experience I knew it was not right. I could have corrected there and then, but didn't
I waited until I could re test with the car metre which was about 5 mins later, it read 6 .8
I re tested with the omnipod ( the metre is built in) again it read 13.8,
Of course it was the strips that where at fault,
A phone call and there where changed by the company.
My question is this if pump technology is at a stage where it can control your BG to a good level the metres must always do the same.
Even today by 2nd metre read 5.5 before I drove, yet the omnipod read 4.2.
On MDI I would have eaten a cp to increase before driving
I did on this occasion 2 hours later I was 9.9 on pod and 9.2 on the 2nd metre,
Its OK setting targets but if metres and strips give readings like this it only causes us type 1 more stress and hard work.

I'll add here both omnipod and the metre company where fantastic I couldn't have had better assistance with this matter.
with MDI the difference of 1.5 is acceptable ,but with pumps its not close enough, with more and more products being manufacture in China for cost reasons I hope drug companies keep a close watch an quality control on strips etc.

marke Site Administrator
South East Kent PCT
659 posts

Sorry but I don't know where you get your information. Firstly why do you think more and more products are being manufactured in China and why is this a bad thing ? Secondly why do you think your meters will be highly accurate ? A blood test using a home meter is a best guess its NOT a foolproof accurate reading. Firstly it is carried out in a completely uncontrolled environment with a number of varying inputs. For a start test strips only have to be within 15-20% of the 'real' Blood Glucose value, then you are potentially extracting blood onto a contaminated surface ( your skin), lastly the test strips may have been kept in an environment were the temperature varies wildly. All of these factors can create an inaccurate reading.
I agree it should NOT vary from 6.8 to 17 or 13 that is concerning, however did you use the same sample of blood for each test ? If not other factors could be affecting the result.
I'm not being deliberately difficult here, just trying to point out that you are expecting too much from a technology that will never be able to deliver it. Perhaps once/if we have embedded BG sensors that measure your blood sugar continuously, internally but I suspect this technology is a few years away yet.

JayBee DAFNE Graduate
James Paget University Hospitals NHS Foundation Trust
586 posts

Agreed marke. Even an insulin dose can vary it's behaviour if where it was delivered has lipohypertrophy present (not that I know if youone does or not). It's not that black and white.

Might be worth sharing some diary entries too if you find this is a regular issue for you, youone. Best wishes.

youone DAFNE Graduate
Hull and East Riding Diabetes Network
102 posts

marke said:
Sorry but I don't know where you get your information. Firstly why do you think more and more products are being manufactured in China and why is this a bad thing ? Secondly why do you think your meters will be highly accurate ? A blood test using a home meter is a best guess its NOT a foolproof accurate reading. Firstly it is carried out in a completely uncontrolled environment with a number of varying inputs. For a start test strips only have to be within 15-20% of the 'real' Blood Glucose value, then you are potentially extracting blood onto a contaminated surface ( your skin), lastly the test strips may have been kept in an environment were the temperature varies wildly. All of these factors can create an inaccurate reading.
I agree it should NOT vary from 6.8 to 17 or 13 that is concerning, however did you use the same sample of blood for each test ? If not other factors could be affecting the result.
I'm not being deliberately difficult here, just trying to poinfseart you are expecting too much from a technology that will never be able to deliver it. Perhaps once/if we have embedded BG sensors that measure your blood sugar continuously, internally but I suspect this technology is a few years away yet.



Yes I think your been differcult and avoiding the simple question I asked if pump technology is getting to a point where you can control your BG to what many I've read on here aim for
Is present day BG testing matching this.
In my job if I'm asked to produce a product to a specification the customer doesn't want the if's and buts he wants the item produced to the specification and the item to work with in the parameters written down.
A person with many years experience (type1) most of them years with little or no support know most of the it's and buts that can Effect your BG result this from self education and been responsible for myself.
Not sure what my diary record or how it would help, the question was regard to the Meter reading between a space of 15 mins between two Meters in the same conditions. Milking or the same effects would not give that difference it was the test strips, which have now been replaced my the supplier.
As stated my dairy would not help here since it doesn't explain my life style and since my HbA1c has been between 6 to 7.5 the last 3 years although this is just an average over a period 3 to 6 months.
The reading of 13+ was due to a or faulty test strip.
If in your comment your stating present Meters are only a guide at best then the technology has a bad miss match since the pump has brought my HbA1c down. Only if the Meter was more accurate I could see it been between 5 to 6 that with my life style is a big advancement

.

marke Site Administrator
South East Kent PCT
659 posts

Hi you are entitled to think I am being difficult and not answering a simple question just as I am entitled to think you are not going to listen to what I say. Therefore I won't comment further since it won't benefit anyone for us to argue over medical technology.

Garry DAFNE Graduate
North Lincolnshire
328 posts

Agree with marke.
Here is the content of a post that I wrote in November 2010 on the same subject of meter accuracy when a lady talked of wildly varying BG results:

Most BG kits now use such a small blood sample that any contamination error has a really dramatic effect.
BG 16 to 5.6 in 45 minutes is very unusual.

I say this from experience with an Medisense Abbott Optium Xceed meter which on 5 second Optium Plus test strips uses a tiny blood sample - 0.6 μL.
They did a 3 second strip for a time which used an even smaller blood sample. But not sure whether they are available now.
Anyway I proved contamination error to myself by repeated trials of unwashed hands v washed hands - washed immediately after - and saw errors of up to 8 BG.

My conclusion was that I had to always accept the need for lack of contamination and to stick with washed hands at testing time.




We all want to use small samples for obvious reasons...my finger ends look bad enough already...but we must accept the inaccuracy that goes with the 'instant' result that we demand. We can not expect a piece of kit that your can carry in a pouch, in your pocket, to produce results comparable to a £40 or 50k bench mounted machine set up in an air-conditioned laboratory using a 7 ml sample - or 11,666 times bigger than your instant blood test, to give accurate results...only statistically precise results - and this is the language that meter manufacturers use. I, until I read up on it, misread this as precision - which is wrong. It means...repeatable results under exactly the same conditions...not accurate results.
Hence we are only able to rely on getting repeatable results....may still be inaccurate results...for all the reasons already outlined.
So learn to trust the guidance of your meter and if a wacky result comes up that you do not believe...repeat the test making sure that your hands are perfectly clean....and DRY and see then what you get.

Regards
Garry

novorapidboi26 DAFNE Graduate
NHS Lanarkshire
1,800 posts

I think that the technology used to actually determine blood glucose from a sample of blood is a lot more advanced than what the pump actually does.

A lot of the success of the pump is down to the user. Of course the way it delivers the insulin, slowly over time, does help a lot, as absorption is much more efficient and it helps with varying digestion times.

I think in your case something has went wrong with the meter, maybe the strips, but I think a replacement of the strips or meter would fix your problem.

Does your meter wirelessly transmit the reading to the omnipod?

Vickyp DAFNE Graduate
Durham Diabetes Network
137 posts

I am on the Omnipod and if I get a rouge reading - where I know its not right ( I roughly know when I dip below 4.5 and am over 10) I retest with an other strip...I only use my other meter for ketone testing - was always told to only use one meter due to the result being unreliable.
I know that all strips should work correctly but NOTHING ever works 100% correctly 100% of the time!

Also me being me at 5.5 before driving I would still have atleast 1 CP...as I could be on a dip and don't want that to happen whilst driving anyway.

novorapidboi26 DAFNE Graduate
NHS Lanarkshire
1,800 posts

Is the cp before driving just precautionary.........?

Has there been times when you have dipped because you didn't take on a carb?

Vickyp DAFNE Graduate
Durham Diabetes Network
137 posts

I have random dips but can almost guarantee one whilst driving! Especially if I am driving in the morning or mid afternoon...last summer I dropped from 10.8 ( had breakfast with no bolus!) to 3.4 within 1.5hrs of driving!
If on long journeys I always stop BEFORE the 2 hour limit, generally around 1.5hrs and generally always eat before driving if going to be driving for more than and hour!
Doesn't always work as at Christmas had 2cps as was 4.4, got upto 5.5 before driving, assuming I would rise further having had 2 cps but just 45 minutes later was at 4.0!