Constantly high readings? Faulty?

J

Jhp86

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Type 1.5 LADA
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Hi,

So placed my sensor on Saturday and my readings were a little off from my finger pricks, but not by loads.

Since yesterday they’ve been really high, and definitely higher than the finger pricks, up in the mid to high 20s where as when I’ve tested to see, it was in high teens!

Not sure if it’s cos of where I put it, which was the back of my arm, or if it’s just faulty? I’ve contacted Abbott, taken it out and will leave it a day till I re apply.

Has this happened to anyone before???
 
One of the limitations of CGMs is that they read most accurately at "normal" levels
If your BG is in double figures, they are extremely unreliable.
If your BG is in the high teens, it suggests you need more insulin to bring it down. In the meantime, all you can get from your Libre is that your BG is too high
 
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As @helli says, that’s your problem @Jhp86 Your high blood sugars have affected the accuracy of the Libre. If your blood sugars were in range, you might well have found it was ok. I wouldn’t have removed it unless it was still very inaccurate when your blood sugar was back in range (allowing time for it to settle).

Why were your blood sugars high? Have you sorted them out now?
 
The back of the arm is the only place libre is licensed for in the uk, i think, so no problems with the placement.
All cgms are less accurate at high figures. mid 20s compare with high teens doesn't suggest a faulty cgm to me.
 
It is a shame that you didn't post this before removing it.
I too would say that your sensor was not faulty but your expectation of it probably is. 🙄 Understanding the limitations of CGM is really important but also you should know that your BG meter is not that accurate either and especially when you are well above range. They have to be within 15% of your actual reading 95% of the time I believe and obviously the higher your BG is, the bigger that 15% becomes, so it is possible that if your finger prick is reading 15% lower and your Libre is reading 15% higher then they could easily be that far out and both still be acceptable and working fine. The decimal place gives us a very unrealistic expectation that it is accurate when it isn't.
Once you get down into range you will find much less disparity. I have just done 2 consecutive finger pricks and got 14.9 and 12.3 from the same finger prick about a minute apart on the same BG meter. I am not surrently using a Libre. I am reasonably confident from those 2 tests that my actual level is probably about mid 13s. I am not happy about that reading being so high but I am taking AntiBs for a tooth abscess so my levels are more erratic and I am going to hit it with a correction of insulin now to bring it down. Those two readings just tell me I am higher than I would like and give me an idea of how much insulin I need to bring me down to somewhere about 6, but if I end up somewhere between 4 and 8 that is fine. There is no precision in diabetes just approximations and best guesses.

Also important to know that Libre can be less reliable in the first day or two after application. As a result many of us apply it a day early and give our body time to react to the foreign body that has been fired into it before we actually activate it.
 
Thanks everyone!

@Inka still no clue to why my sugars have shot up, but the new insulin’s seem to be lowering them, so fingers crossed it’ll settle down fully soon.

@rebrascora yeah I mean I wasn’t sure what the best thing was, but I think I’ll reapply tomorrow and then start it the next day so it can fully settle and go from there.

Hopefully my levels will continue to lower and I’ll get there with it all!
 
rebrascora said:
It is a shame that you didn't post this before removing it.
I too would say that your sensor was not faulty but your expectation of it probably is. 🙄 Understanding the limitations of CGM is really important but also you should know that your BG meter is not that accurate either and especially when you are well above range. They have to be within 15% of your actual reading 95% of the time I believe and obviously the higher your BG is, the bigger that 15% becomes, so it is possible that if your finger prick is reading 15% lower and your Libre is reading 15% higher then they could easily be that far out and both still be acceptable and working fine. The decimal place gives us a very unrealistic expectation that it is accurate when it isn't.
Once you get down into range you will find much less disparity. I have just done 2 consecutive finger pricks and got 14.9 and 12.3 from the same finger prick about a minute apart on the same BG meter. I am not surrently using a Libre. I am reasonably confident from those 2 tests that my actual level is probably about mid 13s. I am not happy about that reading being so high but I am taking AntiBs for a tooth abscess so my levels are more erratic and I am going to hit it with a correction of insulin now to bring it down. Those two readings just tell me I am higher than I would like and give me an idea of how much insulin I need to bring me down to somewhere about 6, but if I end up somewhere between 4 and 8 that is fine. There is no precision in diabetes just approximations and best guesses.

Also important to know that Libre can be less reliable in the first day or two after application. As a result many of us apply it a day early and give our body time to react to the foreign body that has been fired into it before we actually activate it.
Click to expand...
Barbara
How did you "hit it with a correction"? Did you go out of Smartguard and do a Manual Correction or pretend you had taken carbs? I usually go high if I underestimate the carbs, or my Type 1 was playing its usual games and generally I tell the 780G I've had more carbs and add enough correction to correct the high. Today at lunch I started going high took another 2 units and 30 minutes later had gone from 12 to 16. I then told the pump I had eaten another 20gms C and had anther 2 units. The BG went down in another 20 minutes to 13 with 2 arrows descending, so it will work out about right.
But no! It has just alarmed me again after 5 minutes with 14.9BG. What happened to the 13 with two arrows descending?
I think irregularities this irregular merit a change of infusor and insulin though I only changed it last yesterday. The 4 sensor has only a few more hours so I might change that as well.
Sorry about all the dramas.
Adam
 
@adamrit I am using injections, not a pump, so I can hit it with as many corrections as I like whenever I like, without having to tell porkies 🙄 to a pump, to get it to do what I need. Sometimes my levels will go high and I have to stack multiple small corrections to get it back down. Like you it will come down a little and then start heading back up again. I am very proactive about using corrections because once my levels get above 10 they just don't want to come back down.
I know that we are strongly advised against stacking corrections but it is the only thing which works for me and I find several small corrections half an hour apart are better than me rage bolusing one big correction.
 
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