Libre 2

[Nixterjoe]

so first time using Libre 2 CGM and I have very different readings to my finger prick tests monitor showing 8 finger prick showing 6 .. which one should I take notice of ? and is that normal :\

 

[Ushthetaff]

due to the nature of the Libre system you will find that the Libre hays a tendency to real lower than actual finger prick , this is because libre doesn’t actual measure your blood, , Libre is also about 10 mins behind your actual blood sugar ,
ive been using liber for many years now and what your experiencing not uncommon ,

 

[Nixterjoe]

thank you, i know i am gonna sound really dumb but what does it actually measure if not blood ?

 

[KennyA]

thank you, i know i am gonna sound really dumb but what does it actually measure if not blood ?

Interstitial fluid, the stuff that's (almost) everywhere in your body - when it's in the lymphatic system, it's called lymph.

I understand that the new CGM models now have some sort of improved algorithm that attempts to cope with both the timing differences and the interstitial fluid/blood differences.

I found the CGM great for showing trends and what was happening at points when I couldn't test - when asleep, or in the middle of strenuous exercise, for example. I kept the fingerpricks for monitoring purposes - so it wasn't an "instead of" for me it was an "as well as".

 

[Deleted member 527103]

due to the nature of the Libre system you will find that the Libre hays a tendency to real lower than actual finger prick , this is because libre doesn’t actual measure your blood, , Libre is also about 10 mins behind your actual blood sugar ,
ive been using liber for many years now and what your experiencing not uncommon ,

Whilst CGMs like the Libre read interstitial fluid instead of blood, that does not mean they have a tendency to read lower than finger pricks.
In my experience over about 5 years is they are as likely to over read as under read (unless you are able to calibrate them).
The only thing I have found which is consistently lower for me is the HbA1C estimate. It is so far out (about 20% lower for me) that I think of it as a completely different metric.

 

[Tony337]

Hi
I too after 5 years of a libre find it reads higher than a finger prick test.
They also take time to bed in so i pop on a new sensor 24 hours before i activate it.
I adore mine and wouldn't be without it.

Good luck

Tony

 

[becca59]

Just done a blood test as I usually do 1 a day if I remember. Libre 7.4 bloods 7.8. Invariably the close proximity is usual for me. And it’s not an an even keel at the moment as I’ve just been for my swim, eaten my raspberries and yoghurt and injected. Libre 1 used to be about 2 out with the 15 minute catch up, but 2 never really has been. Proving once again that our bodies are all different.

 

[cicatrix_alba]

I am finding right now that I am getting 2.5 or LO readings when in fact finger pricks are reading 4 or at the very worst 3.9. Most disconcerting.

 

[pcarl]

Hi All

I have been using Libre for 2 years. I don't finger pick my finger anymore. As has been said Libre does not measure the blood. It measures Interstitial fluid. This can not be compared to Blood finger pick as they measure different things. It one or the other you go by and stick with it.

 

[Tankie70]

The Libre 2 system has now become a Constant Glucose Monitor (GCM), when mine is paired to my phone it gives me readings all day and night if your phone is nearby. When I checked mine against finger pricks it was normally about 1.1 / 1.2 above, with that in mind my alert for low blood sugars is set accordingly, this can also be done for the high reading, when exercising I tend to increase my reading to a fairly high level which normally drops during the exercise.
You may get occasional rogue readings plus sensors, with the sensors that stop giving readings I suggest that you contact Abbott Customer services, it will be replaced, you may also need to return the faulty sensor, with this in mind I suggest that you keep all the packaging until you start your next sensor.
I hope that you manage to out your questions about Libre 2 and accept that it is a better way moving forward rather than constant finger pricks

 

[MuttNJeff]

I am finding right now that I am getting 2.5 or LO readings when in fact finger pricks are reading 4 or at the very worst 3.9. Most disconcerting.

Disconcerting, but common. My experience is that it often (but not always) under-estimates if below 4 and over-estimates if above 10. I also find that the android app frequently has gaps in the graph, even when the phone has been with me, and that if I scan it to update the graph the indicated currnet reading, and trend arrow, often change over the next 2 or 3 minutes.

Summary - it is a help, but not particularly accurate.

 

[nitonboy1]

I am finding right now that I am getting 2.5 or LO readings when in fact finger pricks are reading 4 or at the very worst 3.9. Most disconcerting.

Hi. I had the same problem. When I applied the sensor I hit a tendon or something and bent the pin (& bruised myself!). Contact Abbott and they will send a new one and a return bag for old one. I'm guessing that it is your issue.

 

[kokoloko]

I am finding right now that I am getting 2.5 or LO readings when in fact finger pricks are reading 4 or at the very worst 3.9. Most disconcerting.

I have similar problems, especially at night, my Libre will be reading as low as 2.3 but my fingerprick could be between 5 and 6. I have learnt to listen to my body. I tend to know when I'm going low, even at night.

 

[Quantum Mechanic]

due to the nature of the Libre system you will find that the Libre hays a tendency to real lower than actual finger prick , this is because libre doesn’t actual measure your blood, , Libre is also about 10 mins behind your actual blood sugar ,
ive been using liber for many years now and what your experiencing not uncommon ,

I found

due to the nature of the Libre system you will find that the Libre hays a tendency to real lower than actual finger prick , this is because libre doesn’t actual measure your blood, , Libre is also about 10 mins behind your actual blood sugar ,
ive been using liber for many years now and what your experiencing not uncommon ,

For me the Libre 2 registered both high and low readings. It was very rarely anywhere near accurate, mostly about 2-4 points out After one reading of 17 when I was in fact around 7 I decided to ditch it as being way to dangerous for me. Also because Abbott didn't want to know when I reported stuff like this.

 

[Jaylee]

Just done a blood test as I usually do 1 a day if I remember. Libre 7.4 bloods 7.8. Invariably the close proximity is usual for me. And it’s not an an even keel at the moment as I’ve just been for my swim, eaten my raspberries and yoghurt and injected. Libre 1 used to be about 2 out with the 15 minute catch up, but 2 never really has been. Proving once again that our bodies are all different.

Mine’s normally within 0.6mmol of the meter. It’s only regarding hypo recovery there is a lag..

 

[Ashintheuk]

Disconcerting, but common. My experience is that it often (but not always) under-estimates if below 4 and over-estimates if above 10. I also find that the android app frequently has gaps in the graph, even when the phone has been with me, and that if I scan it to update the graph the indicated currnet reading, and trend arrow, often change over the next 2 or 3 minutes.

Summary - it is a help, but not particularly accurate.

I attended a seminar run by the Diabetes Research and Wellness Foundation charity near Coventry a few weeks ago. The people responsible for the rollout across the entire NHS of CGMs gave a talk (Professor Partha Kar and Dr Iain Cranston) and they stated that CGMs are a whole lot more reliable than traditional blood sugar monitors due to the strips ageing, and risk of contamination with the sample. The difference being that CGM sensor strips are constantly cleaning themselves.

 

[Jaylee]

I attended a seminar run by the Diabetes Research and Wellness Foundation charity near Coventry a few weeks ago. The people responsible for the rollout across the entire NHS of CGMs gave a talk (Professor Partha Kar and Dr Iain Cranston) and they stated that CGMs are a whole lot more reliable than traditional blood sugar monitors due to the strips ageing, and risk of contamination with the sample. The difference being that CGM sensor strips are constantly cleaning themselves.

I was in A&E the other week having some diabetes unrelated tests done. They thought I’d ruptured a spleen, I told em my pancreas was done years ago. Yada yada..
Nurse rocks up how are your bloods? I’ll show you.. lol, without asking she grunted at the CGM reading on my phone & hit my finger with a lancet…

They were both bang on…

 

[Bug457]

I have been using the Libre 2 sensor for about 3 years now, in my experience there can be up to 20% +/- variant from my finger blood sample (5-6 a day). I have noticed humidity, whether I’m sweating, my hydration and lag all play a role in how close the two readings are.
As I never have old blood sample test strips I have never considered this to be a factor. I do find that the trend indication and alarms associated with the phone app really useful and have greatly reduced hypos and hyper. In discussion with the nurses and reading the information with the Libre, it is recommended to follow the blood sample when working out bolas levels. The two systems working together has really helped my control

 

[Marshbb]

so first time using Libre 2 CGM and I have very different readings to my finger prick tests monitor showing 8 finger prick showing 6 .. which one should I take notice of ? and is that normal :\

Hi
I only use the Libre as a guide so that my other half can scan me if she thinks I'm going low. I always trust my finger prick and not the scanner as it only reads the same when my blood is around 11.
I would speak to your diabetic nurse about it

 

[Andy_Nash]

Hi. Usually your finger prick will be more accurate, as long as your hands are clean (if you haven't washed them, things such as food residue can distort the readings, potentially seriously).

The Libre readings have a lag time in reacting to changes in trend of blood sugars. So, for example, if your blood sugars are likely to have started increasing fairly rapidly at the time, the 8 could be where you actually were and the 6 where you would have been if that rapid increase hadn't started.

However, having used Libre for 3 years it is also clear that different sensors tend to be closer to my blood sugars than others. This may reflect differences in their position in the skin but, whatever, it's something to be very wary of. I usually (but not always) find that they trend higher than my blood sugars - sometimes this is by less than 1 mmol/l, but sometimes it is more and sometimes even 2 or more higher (if they're that bad, I report them). They may also be less accurate over the first day or so but, whatever, it's probably good practice after you've attached a new sensor to do a few CGM / finger prick comparisons, preferably not just after you've eaten, to get a feel for how different from your blood sugars that particular sensor is likely to be reading.

I've also proven the variation in readings by doing an experiment with one Libre 2 sensor on each arm for a period of a week. This was fascinating, showing that although both meters had similar broad patterns (picking up peaks, troughs and fluctuations), one of the meters typically gave daily averages from 1.0 to 1.5 mmol/l lower than the other, with the lower one tending to read closer to finger prick readings. While that difference may not sound much, it's certainly important in terms of aspects such as safety to drive, and whether a normal snack might do or you need something sugary.

I still use the system as I feel it's useful and reliable enough to substantially reduce the number of blood tests needed. It's also given me fascinating insight into how my blood sugars move through the day and night, enabling me to achieve tighter control. However, I'd also caution against over-relying on it. If you're going to drive, do a finger prick test too if you're anywhere near the lower end of the safe range. And if you're in doubt at any time do a finger test to check, or (if you think you're going hypo quickly) have some sugar first and then check.