Libre 2 - BG difference from finger prick

[Bruce Stephens]

Brilliant, I can work with a fixed variation and can set alarms based on it

As @rebrascora says, 0.8 is within the range of error of test strips (I think, anyway), so I'm not sure any variation is needed. Just consider the Libre result to be right and work on that. (Verifying now and again to make sure it's still close enough to test strips.)

 

[JamietDE6]

Hi all, read this thread with interest as I have recently started a trial on the Libre 2 which was free. On night one the sensor gave a low alarm that was 4 mmol out when compared with a finger prick. After the initial teething trouble I have to say it has been a revelation and my fingers are so relieved that I don’t have to keep stabbing them. I reported the initial difference to Abbot who have been marvellous and sent a second free sensor without hesitation albeit I did have to complete a form with some lengthy questions. I have now received £100 worth of kit free .
I have to agree with others though that you have to accept the limitation, it does not seem to keep up with fast rising BG levels but that aside the benefits outweigh this limitation. I will have to self fund at the end of my trial as I am as yet undiagnosed between T1/T2. As I am on Metformin and Insulin bolus and basal and not a “definite” regime that fits the NICE guidelines my DSN refuses to prescribe at the moment. I would recommend anyone reading this at least does the free trial as you will be surprised at how much you will learn about your BG levels.

 

[rebrascora]

On night one the sensor gave a low alarm that was 4 mmol out when compared with a finger prick.

If this was whilst you were sleeping (or lying down) then this was likely a compression low and is another limitation of Libre to be aware of. If you lie on the sensor it compresses the tissue under the sensor resulting in an erroneous low reading and is why it is always recommended to double check any lows particularly during the night before you take a hypo treatment unless you clearly feel hypo. Often you can tell if it is a compression low because the graph will show a sudden dip and then when you roll off the arm sensor it will show a rebound usually up above the previous steady level and then will drop back down slightly to the correct level. This is a perfect example if the algorithm over predicting and then settling back to the correct level.
Someone who isn't diabetic posted a graph recently where they were worried about having had hypos in their sleep, which were actually almost certainly compression lows because they demonstrated this profile of sudden drop rebound slightly too high and then settle back to the original level. The sensor isn't faulty in this situation, it is just a limitation of the system. Gradually you learn not to lie on the sensor or to place it in a spot on the arm where it is less likely to happen or you learn to interpret the graph and see it for what it is.

 

[Matchless]

if more people would use Xdrip app half the problems of the above would not exist.

 

[Lucyr]

if more people would use Xdrip app half the problems of the above would not exist.

Except then you’d have to fingerprick before driving because it’s not a medically approved system, and wouldn’t get free replacements when you have sensor problems. The majority of sensors are very accurate with the official app I find.

 

[helli]

Except then you’d have to fingerprick before driving because it’s not a medically approved system, and wouldn’t get free replacements when you have sensor problems.

I got replacements when my sensor failed when using xDrip and used it for driving with confidence.
In fact, I was far more confident using Libre sensors calibrated for my body with xDrip than uncalibrated with LibreLink.

 

[Lucyr]

I got replacements when my sensor failed when using xDrip and used it for driving with confidence.
In fact, I was far more confident using Libre sensors calibrated for my body with xDrip than uncalibrated with LibreLink.

You might feel confident in the accuracy but I wouldn’t be confident that the police, DVLA or your insurance company would agree if it did start being inaccurate and you crashed

 

[UnexpectedDiagnosis]

if more people would use Xdrip app half the problems of the above would not exist.

Can you calibrate against x drip and still have the normal libre app beside it?

Would be curious to run it as a trial tbh. I currently try have a surplus of sensors so why not

 

[everydayupsanddowns]

Make sure you keep well hydrated.

Sensors read values from interstitial fluid, and I find mine are far laggier, slower to respond, and generally much less useful on days where I belatedly realise I've not been drinking enough water!