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Dexcom g4 'exaggerating'?

shivles

shivles

Well-Known Member
We are 24hrs into the dexcom and I'm finding it tends to give a more extreme number than the reality. For example the meter caught a post meal peak of around 11mmol but the dexcom says 13mmol, a 4.1mmol translated as 3.9mmol. Is this typical? Will it improve as more time passes and we calibrate more?
 
@shivles thats both within the 20% tolerance of the sensor and at 4.1 i would still be treating a little for a hypo anyway because you need to look at the 'true' blood sugar being somewhere between the dex and meter. Neither at 100% accurate I'm afraid.

You might find it settles in a bit more. I'm always very happy with dex and meter being within 1 mmol of each other.
 
Try not to over calibrate - you mention sugar surfing? Check what ponder says on calibration.

Try not to calibrate when you are at the extreme high and low. That upsets it!
 
Engineer88 said:
@shivles thats both within the 20% tolerance of the sensor and at 4.1 i would still be treating a little for a hypo anyway because you need to look at the 'true' blood sugar being somewhere between the dex and meter. Neither at 100% accurate I'm afraid.

You might find it settles in a bit more. I'm always very happy with dex and meter being within 1 mmol of each other.
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Oh yes I treated as it was downward trend too :)

Just curious, learning to take into account the lag time plus discrepancy... also don't want the DSN reviewing the readings and thinking she's been that low! It said she went down to 2.9mmol before but lowest meter reading was 3.9, now it says she's 3.7 but meter is 5.6...

Just learning how to interpret it
 
catapillar said:
Try not to over calibrate - you mention sugar surfing? Check what ponder says on calibration.

Try not to calibrate when you are at the extreme high and low. That upsets it!
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Oh yes the rep said max 4 calibrations a day, it asked me for one at 3am last night and I put one in this morning when she was trending level in the 5s
tim2000s said:
The other thing you should avoid is overcalibrating. That makes the readings tend to worse rather than better.
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shivles said:
Oh yes I treated as it was downward trend too :)

Just curious, learning to take into account the lag time plus discrepancy... also don't want the DSN reviewing the readings and thinking she's been that low! It said she went down to 2.9mmol before but lowest meter reading was 3.9, now it says she's 3.7 but meter is 5.6...

Just learning how to interpret it
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ahh right ok, yes it may well take 20 mins or more to come back completely into line post hypo. It can vary a bit but youll get the hang of it ;)

How are you finding it overall?
 
Engineer88 said:
ahh right ok, yes it may well take 20 mins or more to come back completely into line post hypo. It can vary a bit but youll get the hang of it ;)

How are you finding it overall?
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Very reassuring! Also very interesting, will be great to see over the 2 weeks how her days compare
 
It's made me realise that giddiness and silliness with her is a sign of an impending low which is also great as I really struggle with spotting her hypos before they happen since she can't tell me she feels funny
 
It will take a while for you to become a bit more at ease with Dexcom technology. The sensor will start to become a bit more in line with bg readings after about 2 days and once you've adjusted the basal along with the bolus to be a bit more correct, the sensor should be about a 0.4 to 0.7mmol difference to a bg reading. Just remember to wash hands and dry them on something that hasn't been contaminated with a substance that will give a dodgy reading.

Try not to get overly worried at the clinic because they will not only upload the Dexcom data but also bg data as well so HCP know that the technology isn't perfect but is a good guide.
 
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