Freestyle Libre - huge reading errors

[cairntoul]

Hi folks, just ordered a freestyle libre and inserted the first sensor yesterday.

After an hour I took the first reading: 16mmol. Confirmed with phone app and the libre meter. So I performed a stick test: 8mmol.

Performed multiple tests over the next two hours - similar results.

Later in the evening (give it time to settle I thought), the Libre reading was 8 the finger 5, so perhaps getting there?

This morning, Libre reading 9, finger reading 5.

I repeated this with multiple lifescan finger sticks from different packets and using 3 lifescan meters. All show the libre sensor having a massive error - up to 100%.

Now had I dose adjusted based on the Libre readings there would have been serious consequences.

So just wondered whether anyone had seen the same issue.

The data is there, the sensor scans, but the data is dangerously wrong. Dose adjusting on it would be catastrophic in this case.

Difficult to contact Abbott by phone as the number is not free, but potentially very expensive, for mobile users (another annoyance), which makes it very difficult for working people to get a hold of them.

Cheers

 

[grovesy]

I am not a user but there are many on here who are! I am sure they will be along soon!

 

[eggyg]

I'm now on my 8th sensor and apart from the first one where it showed I was constantly hypo for 24 hours, mine have been more or less spot on. Some say it could be dehydration, perhaps try drinking more water. If you haven't already, join the Abbott Freestyle Users Facebook page. Loads of advice. Hope you get it sorted, it's a very useful tool. Oh and by the way, welcome to the forum, we're a friendly lot, if maybe a bit nuts at times! Elaine 🙂

 

[AndBreathe]

Hi folks, just ordered a freestyle libre and inserted the first sensor yesterday.

After an hour I took the first reading: 16mmol. Confirmed with phone app and the libre meter. So I performed a stick test: 8mmol.

Performed multiple tests over the next two hours - similar results.

Later in the evening (give it time to settle I thought), the Libre reading was 8 the finger 5, so perhaps getting there?

This morning, Libre reading 9, finger reading 5.

I repeated this with multiple lifescan finger sticks from different packets and using 3 lifescan meters. All show the libre sensor having a massive error - up to 100%.

Now had I dose adjusted based on the Libre readings there would have been serious consequences.

So just wondered whether anyone had seen the same issue.

The data is there, the sensor scans, but the data is dangerously wrong. Dose adjusting on it would be catastrophic in this case.

Difficult to contact Abbott by phone as the number is not free, but potentially very expensive, for mobile users (another annoyance), which makes it very difficult for working people to get a hold of them.

Cheers

Cairntoul - I am a part-time Libre user, and I am a real fan. It is by no means perfect, but it has taught me a great deal about how my body functions, in the background.

One thing I will say is though is that some people (including me) find their sensors can be a bit,. erm,......... erratic during the first 24 hours, after application. If you ring Abbott today and describe your sensor's activity, my guess would be they would want to know if it settles after another day.

Personally, having done lots of reading on people who are actually using the Libre, I now apply a sensor than eave it for 24-48 hours (usually 48 hours for me), before activating it. Curiously enough, I have had far fewer "weird" sensors since doing this.

My theory is that some folks (including me) have quite a strong reaction to the application process - probably he puncturing of the skin), and recognising the foreign body under the skin (the Libre filament) it tries, with it's natural powers of healing, to reject the filament (like it would a splinter), by a fairly typical inflammation response - redness (although probably under the sensor), and very minor little swelling (flooding with body fluids) , before "getting used to" the sterile filament after c24 hours and settling down to give more reasonable readings.

Obviously, that isn't deep science, but it hangs together fr what happens to me.

In your shoes, I'd try to sit it out for another 24 hours or so, and see how it goes, then, if necessary, call Abbott to discuss it. Their support services are very good.

For future sensors, it could be worthwhile applying the new sensor and allowing it the c24 hours to settle and see how that works out for you.

Enjoy!

 

[DeusXM]

Hi folks, just ordered a freestyle libre and inserted the first sensor yesterday.

After an hour I took the first reading: 16mmol. Confirmed with phone app and the libre meter. So I performed a stick test: 8mmol.

Performed multiple tests over the next two hours - similar results.

Later in the evening (give it time to settle I thought), the Libre reading was 8 the finger 5, so perhaps getting there?

This morning, Libre reading 9, finger reading 5.

I repeated this with multiple lifescan finger sticks from different packets and using 3 lifescan meters. All show the libre sensor having a massive error - up to 100%.

Now had I dose adjusted based on the Libre readings there would have been serious consequences.

So just wondered whether anyone had seen the same issue.

The data is there, the sensor scans, but the data is dangerously wrong. Dose adjusting on it would be catastrophic in this case.

Difficult to contact Abbott by phone as the number is not free, but potentially very expensive, for mobile users (another annoyance), which makes it very difficult for working people to get a hold of them.

Cheers

Isn't it a global freephone number? http://www.freestylelibre.co.uk/help-center.html

Some sensors are just genuinely 'wrong' - Abbott usually replace these FOC.

For the record, I've been using a Libre constantly since December 2015 and haven't ever had an issue with inaccurate readings except for within the first 24 hours, where the sensor tends to read about 1.5mmol/l lower than a fingerstick.

 

[Owen]

Cairntoul - I am a part-time Libre user, and I am a real fan. It is by no means perfect, but it has taught me a great deal about how my body functions, in the background.

One thing I will say is though is that some people (including me) find their sensors can be a bit,. erm,......... erratic during the first 24 hours, after application. If you ring Abbott today and describe your sensor's activity, my guess would be they would want to know if it settles after another day.

Personally, having done lots of reading on people who are actually using the Libre, I now apply a sensor than eave it for 24-48 hours (usually 48 hours for me), before activating it. Curiously enough, I have had far fewer "weird" sensors since doing this.

My theory is that some folks (including me) have quite a strong reaction to the application process - probably he puncturing of the skin), and recognising the foreign body under the skin (the Libre filament) it tries, with it's natural powers of healing, to reject the filament (like it would a splinter), by a fairly typical inflammation response - redness (although probably under the sensor), and very minor little swelling (flooding with body fluids) , before "getting used to" the sterile filament after c24 hours and settling down to give more reasonable readings.

Obviously, that isn't deep science, but it hangs together fr what happens to me.

In your shoes, I'd try to sit it out for another 24 hours or so, and see how it goes, then, if necessary, call Abbott to discuss it. Their support services are very good.

For future sensors, it could be worthwhile applying the new sensor and allowing it the c24 hours to settle and see how that works out for you.

Enjoy!

I am watching this as I am considering using this system.

If you are applying the sensor and leaving it 24hrs, does this mean a gap in monitoring, or do have the old sensor still in operation?

 

[Sally71]

I am watching this as I am considering using this system.

If you are applying the sensor and leaving it 24hrs, does this mean a gap in monitoring, or do have the old sensor still in operation?

Yes you can insert the new sensor while the old one is stil running, and just don't activate it straight away. You can't actually have 2 sensors active at the same time, if you start the new one before the old one has finished then you can't read the old one any more. But for the purposes of allowing the new sensor to "bed in", you don't want to start it straight away anyway, perfectly fine to have it just sitting there doing nothing!

 

[Owen]

Yes you can insert the new sensor while the old one is stil running, and just don't activate it straight away. You can't actually have 2 sensors active at the same time, if you start the new one before the old one has finished then you can't read the old one any more. But for the purposes of allowing the new sensor to "bed in", you don't want to start it straight away anyway, perfectly fine to have it just sitting there doing nothing!

Does this eat into the 14 days when not activated?

 

[Diabeticliberty]

Isn't it a global freephone number? http://www.freestylelibre.co.uk/help-center.html

Some sensors are just genuinely 'wrong' - Abbott usually replace these FOC.

For the record, I've been using a Libre constantly since December 2015 and haven't ever had an issue with inaccurate readings except for within the first 24 hours, where the sensor tends to read about 1.5mmol/l lower than a fingerstick.

The global freephone number is chargeable to mobile phones.

You are all aware that I have had similar issues to the ones report in the original post in this thread. When I have spoken to a number of other users face to face after an initial 'the system is perfect' conversation most users concede that they have had similar issues too. Don't get me wrong the system does have some advantages which is why I have elected to stick with it. Please do not fall into the 'Emperors new clothes' trap though. We all have a responsibility to potential users to report benefits and liabilities with equal measure

 

[AndBreathe]

Does this eat into the 14 days when not activated?

No. I have done this for about 10 sensors now.

 

[Sally71]

Does this eat into the 14 days when not activated?

No the 14 days goes from when you activate it. You lose an hour of use while it's initialising, but that's all (and unfortunately there's no way of overlapping the old sensor to get round that problem, once you've initialised a new sensor the old one can't be read any more)

 

[DeusXM]

The global freephone number is chargeable to mobile phones.

Actually, that's entirely dependent on network. I believe it's free on O2 and Three, but worth double checking.

Abbott also have a UK freephone number as well - http://www.abbott.co.uk/contact.html - 0800 170 1177, which may also be able to help with any enquiries.

 

[Diabeticliberty]

O2 charge me for ringing the number and I am on a business contract. I am going to ring them immediately and question why they insist on charging me and not you?

 

[Diabeticliberty]

For the record I would once again hope to clarify my own position on this system. To the Libre Cheerleading Troupe I am certainly not anti or I would not still be using it every day and have done since buying it. I do feel however that there are a large number of users who just glibly accept what the system tells them no matter how bizarre the results appear. I am also opposed in principle to waxing lyrical about a system that has a number of flaws and not speaking out about them. I also still cannot comprehend how many of you just choose to ignore these flaws. Potential users who may just about be able to fund the system, should be fully aware of all of the facts before they go either investing in a system that may prove highly beneficial to their diabetic control or may prove to be a complete waste of money and nothing more than a fancy electronic paperweight 🙂

 

[Owen]

For the record I would once again hope to clarify my own position on this system. To the Libre Cheerleading Troupe I am certainly not anti or I would not still be using it every day and have done since buying it. I do feel however that there are a large number of users who just glibly accept what the system tells them no matter how bizarre the results appear. I am also opposed in principle to waxing lyrical about a system that has a number of flaws and not speaking out about them. I also still cannot comprehend how many of you just choose to ignore these flaws. Potential users who may just about be able to fund the system, should be fully aware of all of the facts before they go either investing in a system that may prove highly beneficial to their diabetic control or may prove to be a complete waste of money and nothing more than a fancy electronic paperweight 🙂

I have just come off the phone to customer sales, support. Sadly this system is not ready to meet my requirements at this moment in time.
I will not reduce finger pricking due to being on the road so much.
Hopefully as accuracy improves and is recognised, I will have another look. The concept is great.

 

[Sally71]

For the record I would once again hope to clarify my own position on this system. To the Libre Cheerleading Troupe I am certainly not anti or I would not still be using it every day and have done since buying it. I do feel however that there are a large number of users who just glibly accept what the system tells them no matter how bizarre the results appear. I am also opposed in principle to waxing lyrical about a system that has a number of flaws and not speaking out about them. I also still cannot comprehend how many of you just choose to ignore these flaws. Potential users who may just about be able to fund the system, should be fully aware of all of the facts before they go either investing in a system that may prove highly beneficial to their diabetic control or may prove to be a complete waste of money and nothing more than a fancy electronic paperweight 🙂

Just to balance that - yes I'm one of the "cheerleaders" as you call them. Yes, I love the system. And that's because we have hardly had any problems at all with it. I'm hardly going to report problems that aren't there, am I! Whether we are exceptionally lucky, I don't know; I'm not trying to say that those of you who have had problems with the system are liars, just that we haven't had the same problems!
We had one sensor that failed, returned it and got a free replacement. Another fell off because my daughter bashed her arm against a door, not a manufacturing fault so I didn't send that one back. Apart from that they have all worked and stayed in with the help of some Tegaderm (although to be honest we just stick that on out of habit now, it might not be strictly necessary every time, but when you pay £50 a pop you want to make sure you don't lose the thing!) Regards accuracy, we still do finger pricks in order to work out boluses anyway, as far as I understand it no CGM system is as accurate as a finger prick because it isn't reading blood. But if we read the Libre at the same time it's almost always within 2 mmol of the finger prick, which is close enough and within accepted tolerances. We had one sensor that was a bit further off, but it still read high when she was high, low when she was low and in the middle when she was in the middle which is close enough for me. I'm not particularly interested in analysing everything in detail and trying to predict the next HbA1c, but I do like having a rough idea of what goes on in between finger pricks, and I love the arrow that tells you whether the BG is rising or falling, that alone makes the system worth it for me.

As with anything, some people will love the system, some will hate it and some will be somewhere in the middle. I guess it partly depends on how you want to use it, and also probably on a lot of luck!

 

[cairntoul]

Folks, thanks for the input.

I was aware, anecdotally, of people having a 24hour bed in time. However this it's not mentioned anywhere in the manual (from what I can see), and there's a big difference in an error of 1,2 or even 3 mmol/L and one of 8. Even after 15 hours the error was huge (libre 9, finger 5). Then after 21 hours Libre 14, finger 8.

I did phone. The advisor did say that this could happen, but acknowledged that it was not explicit anywhere.

So someone sticks in a sensor, waits 1-24 hours then dose adjusts... Doesn't give a lot of confidence in the product.

I have graphed the data. The error (for this sensor anyway) is much less at much lower readings. This indicates it gives visibility of low blood sugars. However at mid to higher readings it is miles out. Looks fairly linear too.

So should we be doing finger sticks to check the sensor after application? Again no mention of this...

Cheers

 

[Sally71]

Yes, we do, not every time though. I would NEVER dose adjust based on the Libre alone; although actually, the way my daughter's pump works is that the only way to get her BG reading into it is by finger pricking. So that's still 3 pricks a day; we scan the Libre at the same time as a check. Must admit I've never had one as far out as yours (could still happen though!). So if you are hoping that the Libre will completely remove the need for finger pricks then you will probably be disappointed. We have reduced the number of pricks we do by at least half though, another time the Libre is brilliant is when you are having one of those nasty hypos that takes ages to come up again; you can scan as many times as you like and as soon as the arrow starts pointing upwards you know you will be ok. Much better than loads of finger pricks!

 

[Northerner]

So if you are hoping that the Libre will completely remove the need for finger pricks then you will probably be disappointed

I think Abbott are pretty much responsible for this belief, seeing their recent advertising - the need to check with fingerpricks is 'small print' i.e. something they don't expect most people to read, but they have to state somewhere for legal purposes - a major bugbear of mine, 'small print' should be banned! 😱

I'm considering trying a Libre myself. I have pretty good control, but I'm sure there are some circumstances I'd find surprising, and that I could take action over 🙂

 

[Diabeticliberty]

I'm considering trying a Libre myself. I have pretty good control, but I'm sure there are some circumstances I'd find surprising, and that I could take action over 🙂

I would offer you the same advice as I would offer anybody else. Think very long and very hard about it. What they tell you over and above fingerprick testing is extremely limited and may not be worth over twelve hundred quid per year to you. In my in case the reduction in the need for fingerprick testing due to my occupation driving zillions of miles and lifestyle does make it worth it for me. This is obviously not the case for everybody and I urge any potential users to bear this in mind before buying. The discussion on here is good because you are such a fantastic moderator that you encourage everybody with a view to express it freely 😉