New to Freestyle Libre

John_H

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V excited to be trying out the Freestyle Libre sensor for the first time. I've only had it on for an hour and finger pricking tells me I'm just under 5 mmol/l. The sensor tells me I'm just under 3mmol/l. Is it usual for it to be inaccurate for a short while after initial application? Also, any recommendations for the least expensive method for getting my next one?

Regards

John
 
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GrantGam

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Comrades

V excited to be trying out the Freestyle Libre sensor for the first time. I've only had it on for an hour and finger pricking tells me I'm just under 5 mmol/l. The sensor tells me I'm just under 3mmol/l. Is it usual for it to be inaccurate for a short while after initial application? Also, any recommendations for the least expensive method for getting my next one?

Regards

John
Hello, it's a very good system - I'm sure you'll love it.

A lot of us find that it's best to leave the sensor 'un-started' for 12-24 hours before firing it up. I think it allows trauma at the insertion site to calm down a bit.

There's also the latency issue as well, so you might find the Libre value to be 10-20 minutes behind your actual BG. This can be an issue when your BG is rapidly changing.

There is no least expensive method for sourcing the Libre sensors. I think they're about £48 from Abbott direct after the VAT has been deducted.
 

Juicyj

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Well done @John_H it's a great investment - sadly as said they cannot be gained by any other means than through Abbott, however think about perhaps using they say every other month to monitor and see if you need to adjust, I only wear mine when on hols or doing an activity that requires more monitoring than usual so that i'm getting maximum benefit without spending a fortune.
 

Kwisj

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Hi John the Freestyle Libre sensor is a very useful tool, but like everyone else has pointed out there is a latency issue with it. You'll still have to use the blood test during the day, although you need to do that much less. My poor fingers were swollen on the ends due to over 30 years of sticking needles into them to draw blood, but now they nearly look like normal fingers. I've been using the sensor for about a year now. If you have a problem with a hypo you shouldn't really use it; it's not fast reacting enough. Stick to blood testing. The great thing about the sensor is you can use it whilst you are driving or in places like the cinema where you feel a bit awkward taking out the blood testing kit, etc. etc. Also the little arrows give you an idea if your blood sugar is falling, or rising rapidly which can be quite a help.
The software is very useful for the diabetic team as you can bring them in print out of the last 3 months worth of test results, and they can identify issues with your daily routine. It also gives you an estimated result of your HbA1c which in my case is normally pretty accurate.
it certainly gives you more freedom with your daily routine
Take it easy
Kwisj
 

Bluey1

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I have only had it for s short while, but love it. I have found it to be about 10min lagging. As for accuracy who knows. Using the Neo and the Libre with strips and the same blood seconds apart they never matched each other, so who knows what is even close to accurate, however I suspect the Libre as I was feeling a bit Hypo, the Libre said 4.0mml/l an the blood readings were around 5.8. I suspect all were reading high (as 4 is not Hypo range).
 

gavin86

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Most likely it will get a bit more accurate after a day-ish.

As mentioned above, even different blood meters vary a bit. You will get the hang of judging Libre accuracy. Every now and then a sensor will be ******, but most are good and they'll happily replace the odd bad one
 

ringi

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There's also the latency issue as well, so you might find the Libre value to be 10-20 minutes behind your actual BG. This can be an issue when your BG is rapidly changing.

What is the latency with a "finger pick" test? (I know it is a lot less then with a libre, but does how long does it take for the blood in the finger tips to get replaced with new blood.)
 

GrantGam

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I really don't know, but I'd hazard a guess that it's not long at all. Fingertips apparently have the least latency, and that's it's commonplace to test from there.

I'd also reckon that the blood is replaced almost continuously.
 

ringi

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I though main blood veins had lower latency and the lowest latency of all is the blood that has just left the intestines. But practical issues do come into it as well……

Hence the great benefit of knowing the rate of change as well as a “spot” value when trying to control any system with latency in the feedback cycle. (I have worked on the software for too many control systems over the years, one with a latency of over a day.)

The pancreas gets to “cheat” as it gets messages from the intestines before the BG is added into the system.
 

GrantGam

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I though main blood veins had lower latency and the lowest latency of all is the blood that has just left the intestines. But practical issues do come into it as well……
I meant in terms of testing.

Hence the great benefit of knowing the rate of change as well as a “spot” value when trying to control any system with latency in the feedback cycle. (I have worked on the software for too many control systems over the years, one with a latency of over a day.)

I understand what you're saying, but even if you knew the exact delay period between your actual BG and measured BG, how would that benefit you?
 

Bluey1

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This Libre is amazing. For breakfast and lunch I peak at about 9mmol/l and I'm over 8 for about 15min. Around 6pm I have a little hypo tea around 7pm and I just go up to 14mmol/l by about 0:30 I'm back down again and stay around 4.5mmol/l for the rest of the night. I suspect my issue is the Lantus has run out. I also need another short acting at the same time as I take the daily Lantus at 10:30pm. I was never confident to agressvly chase a high at night as I always woke up low in the morning and Nypo's terrify me, I have lost one friend to a suspected Nypo. Knowing how the short acting behaves and how I behave at night, this has given me the confidence to really tighten things up.
The reader does not cost much more than a normal Blood Glucose meter and it uses the same test strips as the Optium Neo (and some other Abbott meters) so do yourself a favour get another 'spare' meter and just use a sensor a couple of times a year. You can never have enough spare meters. You will learn more about your BSL in a few days than you have discovered over years.
A word of warning to anyone that is new to this D game and this is your first meter, it doesn't come with a lancing device or a nice little pouch. Until I come up with a better solution, my Neo BGM is now a 'spare' and it comes for the ride to carry strips and the lancet, however I'm quickly starting to rely on the Sensor.

This is a serious game changer as the other systems cost a lot more and are more designed around continued use, this can be a normal meter for many months and become a continuous meter once every so often if you are on a tight budget. The insertion of the sensor on the arm is painless and easy to do and you quickly forget it's there.
 

jmparkview

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I've been using the Freestyle Libre since March. It's brilliant! I don't finger prick any more unless I'm driving long distances, or feel unsure as to whether I'm having a hypo. The Abbott Customer Care team are good - a sensor fell off last week, and they've replaced it for free.

It is expensive, but I am using it after attending the BERTIE course to learn how to carb count, and in conjunction with my diabetic nurse. The plan is to get my insulin / carb ratios appropriate for each meal and my daily routine, and to learn how different things affect my blood sugar levels - exercise, stress, alcohol (!) etc etc. The graphs which one can print out enable one to track all these things. My HBA1c has already improved, my peaks and troughs are ironing out nicely as I / we are applying what I've learned through the data I've gathered. Eventually, I hope either I won't need to wear it all the time, because my insulin regime will be correct, or that the price will drop as competitors develop new products!

I've even got over the horrid look of the thing - was brave enough to wear a sleeveless party dress this weekend!
And please, Abbott, if you have someone who reads these things, please think about introducing some colour variations…...
 

Fleegle

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Hi - I have had the Libre since May. My experience has been as others have said - in the first couple of days readings lower than truth and in general a little lower. In saying that who knows what is telling the absolute truth given blood meters compared back to back do not say the same thing. I find mine is never more than .5mmol out well within the 15% meters need to be accurate to. And I find the increase and decrease to be very accurate and very helpful with food spikes particularly with telling you peek time and value. Make sure you record food on the meter just before you eat it and then when you download into the software you get a marker which tells you at what time and what value your peek was. You miss that with the one and two hour meter test.

The lag is between 5&10 mins. The fluids in the skin respond later. It is interesting when you download the figures because the graph seems to correct time somewhat and the asterix's of BG test are nearly on the curve (providing you use the inbuilt BG meter).

I try to not scan so often now because the one time scan can be a little misleading where the 15min graph line seems more like an average in that 15min so you get a far better feel of the trends. Ok you might miss an absolute peek in that 15mins - but if it is high leading up to and following it all comes out in the average anyway. Really interesting also to see stress, tiredness and physical activity.

I try and put my sensor on two days before I activate it for best results. However, warning - one early morning I scanned the wrong one and then accepted the start new sensor :) Now that was the worse of both worlds - ended a sensor two days early and had no warm up on the other one :)
 

Copernicus

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168
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I've been using this system now for over 18 months and it's great. I don't finger prick anymore, I've never had a hypo and I only wish it was available on the NHS. Any problems I have had with sensors, Abbott have replaced no questions asked. I don't understand why the NHS won't supply these as the cost of test strips must just about be the same per month..
 

Bluey1

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Has anyone changed their behaviour once they have started wearing the sensor? I know we are only cheating ourselves, but now I know my Endo wants to see ALL my results, I'm more conscious of what I eat (and drink, especially alcohol as I never go near sugar drinks). As I can see where the BS is going, if it's going up or flat and it's high around bed time, I don't hesitate in whacking in a bit more fast acting. We also have another incentive as in Victoria, you have to get your Drivers Licence approved every year, if you are over a HBa1c of 9 your licence will be suspended.
Does anyone else behave differently with the sensor attached?