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I had a diabetic coma and freestyle libre measured my blood sugar as 22mM

J

John B. March

Member
Messages
5
Type of diabetes
Type 1
Treatment type
Insulin
Ok. This is pretty **** serious. Family found me in a coma last night. Scanned my sensor. 22mM. So they thought it was something else. I'm exhausted and incredibly lucky to be alive. Too tired to write up fully but I wonder how many people have died through faulty readings?
 
You mean a hypoglycemic coma and the freestyle said you were 22mmol/L ???

They aren't always accurate unfortunately. Had you been giving yourself extra insulin to dose for the false high?

In my experience (libre followed by dexcom), if you get an unexpected reading it's best to double check with a glucometer. (Though in my case it's usually false lows).

Hope you feel better soon.
 
Ok. I had spent four days travelling from Vancouver to Scotland and then to Australia so my body clock was totally messed up- I use Lantis and Novorapid. My blood sugars were all over the place, not helped by extensive periods when the sensor gave error warnings- "try again in ten minutes" which often took two hours before I could get a reading.

These errors had been going on for days. I assumed it was the travel, but now I realise it was the sensor system.

So, I arrived in Australia. Pretty exhausted. Apparently high blood sugar all the time. I simply couldn't get it down according to Libre. So I took 16 units, lay down for 30 minutes for a snooze before everyone came round. They found me in a coma. Measured my sugar. 22mmols. A few minutes later it was apparently 8.9.mmols. so not a hypo as far as they were aware, but odd that the readings fluctuated so much. They phoned my son in the UK. He suggested taking a finger prick. They eventually found my old BM reader and sticks, tested on that, reading under 2. At that point they realised it was a hypo and gave me sugar. Without that I would be dead.

I am really, really angry. The libre told me my sugar was high when it was low, so I dosed with insulin when I should have eaten. When I went into the coma it told my family my sugar was high so they didn't give me sugar when it was actually low and that was the cause of the coma.

It has happened to me and I am lucky to be here. This must have happened to others before me How many who were not so lucky is what I wonder?

A system that can give readings 10x too high???
 
At the beginning of this year I was angry that my medical team would not let me have a Libre , now reading on the forum about all the problems people seem to be having with them and especially this one which does sound frightening I think I'll stick with my trusty finger pricks !
 
becca59 said:
I am very sorry for your dreadful experience. However, the advice in the Libre literature is always test highs and lows with a blood glucose meter before treating.
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That's no excuse at all and complete nonsense. I don't even have sticks to measure my blood sugar. I haven't had them prescribed since I started using the libre. A device should never tell you that blood sugar is too high, especially 10x too high. It happened to me and I am lucky to be alive. If it's happened to be I'm pretty certain it has happened to other people who are probably not here to tell the tale.
 
Why do you have no sticks? Readers or phone could fail so, even if the sensors were 100% accurate (which the electronics are never capable of), you need a back up.
 
Yes in Response is definitely right , if I did get a Libre I would certainly make sure I had a meter for back up !
 
I am very sorry that you have had such a terrible experience, and I understand that you are shocked and dismayed, but please review the documentation on Libre use.

Unusual readings should always be checked against glucometer prick tests (which means you should always have a glucometer to hand).

The following is a quote from this page:

The FreeStyle Libre Flash Glucose Monitoring System Indication of Use
The FreeStyle Libre system is designed to replace blood glucose testing in the self-management of diabetes with the exceptions listed below. Under the following circumstances, use a blood glucose meter to check the current glucose readings from the FreeStyle Libre flash glucose monitoring system sensor:
• Duringtimesofrapidlychangingglucoselevels,interstitialglucoselevelsas measured by the sensor and reported as current may not accurately reflect blood glucose levels. When glucose levels are falling rapidly, glucose readings from the sensor may be higher than blood glucose levels. Conversely when glucose levels are rising rapidly, glucose readings from the sensor may be lower than blood glucose levels.
• Inordertoconfirmhypoglycaemiaorimpendinghypoglycaemiaasreported by the sensor.
• IfsymptomsdonotmatchtheFreeStyleLibreflashglucosemonitoringsystem reading. Do not ignore symptoms that may be due to low blood glucose or high blood glucose.

My personal experience of the Libre is that approx one in 10 is faulty. So far, Abbott have rapidly replaced these without any drama.

I discover the faults by using glucometer tests for comparison, during the first 24 hrs after I activate the sensor.

If your healthcare professional do not understand the need to use a glucometer alongside the Libre, then please educate them - as you have learned, it could be a lifesaver.
 
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It’s not an excuse, it is written in black and white. Why on earth do you not have a finger test backup? Your medical team need to sort this out.
 
In Response said:
Why do you have no sticks? Readers or phone could fail so, even if the sensors were 100% accurate (which the electronics are never capable of), you need a back up.
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I have never been prescribed blood sugar sticks once I got a libre sensor- saves money I guess?
 
John B. March said:
I have never been prescribed blood sugar sticks once I got a libre sensor- saves money I guess?
Click to expand...
Not if you end up in hospital because you cannot test your blood sugars when your phone breaks or when your Libre reports an incorrect high or low and you need to test as Abbott advise. Hospital stays are much more expensive than test strips , especially if you don’t use them often.

In the UK, the rules for driving are that we must have a blood glucose meter with us even though Libre readings are accepted. This is for the reasons described above.
 
I am extremely sorry to hear what has happened.

Anyone in the United Kingdom who believes they may have suffered an adverse medical event that necessitated medical treatment as a result of using one of these glucose monitors not working as it should, I implore you to report that adverse event using the UK Medicines and Healthcare Products Regulatory Agency (MHRA's) "yellow card" reporting scheme.

Assuming you have applied and are using the product in accordance with the manufacturer's instructions, if there is something wrong with the sensors, or the software that it is used with, that may be contributing to adverse medical events, such as unconsciousness, hospitalisation, etc, and needs to be fixed, then the MHRA needs to know about it.

Abbott have released two software updates to their Librelink app over the last 4/5 weeks for Android phones. Following those updates (and following a number of Android smartphone manufacturers upgrading new mobile phones operating systems from 12 to 13) there have been a number of reports of Libre 2 sensors/LibreLink app not working as it should. Including a significant number of users reporting low and/or high glucose alarms not working either at all or only working intermittently.

Abbott need to fix those problems. Yesterday! Particularly for those users who are hypo unaware and are relying on the alarms, especially when they go to sleep at night.
 
Ok so how is one supposed to know when the reader is reading incorrectly? It sounds like you're saying every higj or low reading should be confirmed with a blood test- negating the point of it anyway. No. It is totally unacceptable to have a reader which gives a reading 10x higher than the true state. No excuses. I spoke to my daughter about it yesterday. In fact the first reading was 8.9-totally reasonable and no suggestion of "unusually high". That was at 5.49pm. It was 8.3 at 5.51pm, 21.1 at 6.10pm, 26.2 at 6.22pm. All the while in reality it was under 2 and I was in a coma. How are we as users supposed to know when a reading is false and should be checked with a blood test? I'm really angry about this.
 


I agree it's a total pain when a sensor plays up - especially when you end up in a bad place as you did. I have had several wonky ones that Abbott have replaced.

In my experience getting the ".... Try again......" message from the Libre is a red flag for potential issues. Getting it several times, I would not trust the sensor to look after an aspect of my health. That then coupled with your suggestions that things weren't quite adding up, would make a string of bunting of red flags to me.
The Libre is a tool not a silver bullet for diabetes control. In my experience and observation, nothing is foolproof - particularly not anything manufactured.

Unfortunately, you seem to have been caught up in a bit of a perfect storm of potentials for things going wrong, and they did. In your shoes, I'd be taking that as a very hard lesson learned.

If you feel aggrieved, then raise a yellow card, as others have suggested, and maybe call Abbott for their feedback.

If you drive, it could be worthwhile familiarising or refreshing your understanding of the DVLA's requirements,, as something unfortunate happening could also result in your insurance to becoming invalidated.

https://assets.publishing.service.g...e-to-insulin-treated-diabetes-and-driving.pdf
 
John B. March said:
How are we as users supposed to know when a reading is false and should be checked with a blood test? I'm really angry about this.
Click to expand...

I feel your pain and maybe Abbott's algorithm should flag up a warning when a reading goes from 8 to 21 in 20 minutes?

I'm a dexcom user and find the readings invaluable, but I regard extremely high or low readings with suspicion. Even glucometer readings aren't 100% accurate, though you can do two readings in a row if you get a suspect one.

Medical technology has limitations. I think it was extremely remiss of your team not to give you a back up glucometer and if I were you I would complain vociferously to them.

In my opinion a cgm doesn't replace a glucometer completely, butit does greatly reduce the need for finger pricking.

As someone with reduced hypo awareness my dexcom has prevented a lot of hypos, and incidentally improved my awareness, as in my case too many hypos exacerbate issues with hypo awareness.
 
Unfortunately tech can and does fail, no tech is 100% guaranteed to be flawless - it also normally decide to fail at the worst possible time (for me if its fails its when I'm calibrating just before bed when I certainly do not want to stay up hours for it to sort its life out).

The one I use (that works with my pump) I have to now calibrate 3 times a day anyway, but when I was on the libre and even with the ones I use that need calibration I know/knew I should check if it showed really low or showed high and I wasn't really thirsty/dehydrated, or if it continued to show high after corrections.
 

Absolutely this. Work in IT so huge advocate of better management through tech, 15 years since T1 diagnosis, roughly 4 years or so with libre. Love it, significantly less finger pricking, also became a bit reliant on it and would use old Accu-check Mobile less and less (although always on prescription as originally the libre wasn’t suitable for UK driving) rarely test for ketones etc.

Just finished my week DAFNE course where the impact of hypos, DKA, driving rules etc re-emphasised and the impact on your body and life expectancy without complication - using my old meter WITH libre way more now and now the Ketone meter.

Totally understand your frustration with the tech, I have one fail on replacement on average once every couple of months and ring abbot for a replacement. It’s still way better than lots of finger pricking, but I’d get on to your GP and get those old meter test strips back and a ketone meter whilst you’re at it.

Hope you start to feel better soon!
 
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