Libre sensor replacement

ewelina

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I was wondering when can you request sensor replacement from Abbott. Mine current sensor is not great, and this morning was really playing up. The difference was about 2.8 mmol. Is it enough to request sensor replacement?
 

steve_p6

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Ewelina, you should join the libre group on facebook for the direct answers but if this error is in the sub 8mmol range and you are outside the first 48 hours settling in period then I think you have a case. I can live with a 2 mmol error as long as its consistent but 2.8 is too much to my mind.
 

robert72

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I could forgive it for one reading like that, but if it was always out by a lot then I would request a replacement
 
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AndBreathe

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I was wondering when can you request sensor replacement from Abbott. Mine current sensor is not great, and this morning was really playing up. The difference was about 2.8 mmol. Is it enough to request sensor replacement?

Ewelina - I seem to have had a few sensors go wonky. I sometimes think it must be me!!

If I have concerns, I just call the support line and describe my experience. I never ask for a replacement, but the only time it has not been offered immediately is when they wanted me to test using the on-board meter, so they sent me a small number of strips as I don't routinely use a compatible meter and strips. Once I received the strips and did literally two or three tests, reflecting the issue I was reporting, a replacement was sent straight away.

If I have concerns over comparative readings (strip v sensor), I usually make sure I downloaded the sensor data, then make notes on the resulting spreadsheet to highlight which readings I would like to highlight. I find this helps the call get to the nub of the matter, and allows the technician to quickly gather the data they need to reach their suggested course of action. I'm pretty certain the calculation the technician does is the variance, based upon the usual tolerated meter variances.

These days they also ask where the sensor is being worn, if it is in date, and if the sensor and applicator came from the same batch or kit; I can't recall which.
 
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ewelina

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This sensor has been okish, but it hit me quite badly this morning as I was having a hypo. I will see how it goes in the next few days
 

ewelina

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Ewelina - I seem to have had a few sensors go wonky. I sometimes think it must be me!!

If I have concerns, I just call the support line and describe my experience. I never ask for a replacement, but the only time it has not been offered immediately is when they wanted me to test using the on-board meter, so they sent me a small number of strips as I don't routinely use a compatible meter and strips. Once I received the strips and did literally two or three tests, reflecting the issue I was reporting, a replacement was sent straight away.

If I have concerns over comparative readings (strip v sensor), I usually make sure I downloaded the sensor data, then make notes on the resulting spreadsheet to highlight which readings I would like to highlight. I find this helps the call get to the nub of the matter, and allows the technician to quickly gather the data they need to reach their suggested course of action. I'm pretty certain the calculation the technician does is the variance, based upon the usual tolerated meter variances.

These days they also ask where the sensor is being worn, if it is in date, and if the sensor and applicator came from the same batch or kit; I can't recall which.
Ewelina - I seem to have had a few sensors go wonky. I sometimes think it must be me!!

If I have concerns, I just call the support line and describe my experience. I never ask for a replacement, but the only time it has not been offered immediately is when they wanted me to test using the on-board meter, so they sent me a small number of strips as I don't routinely use a compatible meter and strips. Once I received the strips and did literally two or three tests, reflecting the issue I was reporting, a replacement was sent straight away.

If I have concerns over comparative readings (strip v sensor), I usually make sure I downloaded the sensor data, then make notes on the resulting spreadsheet to highlight which readings I would like to highlight. I find this helps the call get to the nub of the matter, and allows the technician to quickly gather the data they need to reach their suggested course of action. I'm pretty certain the calculation the technician does is the variance, based upon the usual tolerated meter variances.

These days they also ask where the sensor is being worn, if it is in date, and if the sensor and applicator came from the same batch or kit; I can't recall which.
Thank you. I will give them a call. I don't feel confident with this sensor at all now!
 

steve_p6

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That is obviously also a factor, if you do or do not have good hypo awareness then the libre accuracy is much more important to people.
 

AndBreathe

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That is obviously also a factor, if you do or do not have good hypo awareness then the libre accuracy is much more important to people.

I agree with you, but to be fair, the sensor I am currently wearing (which is being replaced) has been just wonky - both high and low, although mainly significantly high. My "working range" is pretty low, so variances of 1.5, say, are significant in terms of accuracy, if not necessarily in terms of how I react to the reading.

I think it's fair to expect that this device will show variances, but such variances should surely be similar those allowable via a meter.

I absolutely love the Libre, but it can be frustrating when the wiggly line gets a lot wigglier than it should! :)
 

steve_p6

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I agree with you, but to be fair, the sensor I am currently wearing (which is being replaced) has been just wonky - both high and low, although mainly significantly high. My "working range" is pretty low, so variances of 1.5, say, are significant in terms of accuracy, if not necessarily in terms of how I react to the reading.

I think it's fair to expect that this device will show variances, but such variances should surely be similar those allowable via a meter.

I absolutely love the Libre, but it can be frustrating when the wiggly line gets a lot wigglier than it should! :)
Yes sorry was replying to Ewelinas reference to hypo, which made me think about hypo awareness, and didnt see your message slip in.
 

robert72

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If it was reading high and you were hypo, that usually triggers replacement.
 
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noblehead

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This sensor has been okish, but it hit me quite badly this morning as I was having a hypo. I will see how it goes in the next few days


Did the Libre not pick up on the hypo at all @ewelina, if your bg was dropping fast in a short space of time ( say after bolusing) then the Libre wouldn't pick up on the hypo until 15-20mins after (if that makes sense), have a look and see what happens on the graph around the time of your hypo.

That said if it's reading 2.8mmol/l out then it definitely needs replacing, hope you get it sorted.
 

ewelina

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Did the Libre not pick up on the hypo at all @ewelina, if your bg was dropping fast in a short space of time ( say after bolusing) then the Libre wouldn't pick up on the hypo until 15-20mins after (if that makes sense), have a look and see what happens on the graph around the time of your hypo.

That said if it's reading 2.8mmol/l out then it definitely needs replacing, hope you get it sorted.
It could have been a rapid drop as it was during my morning walk to work. I noticed that libre has a bit of a time lag but it was a bit funny for whole morning. I started a walk with levels of 12 rising to 13.8. Then dropping slowly to around 8. I tested only beacause suddenly I started to feel a bit dizzy. Libre showed over 6 but in fact I was below 4
 

tim2000s

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@ewelina Abbott state that all of their meters (Blood and Libre) should perform within a MARD of 15%.

In practice what this means is that if the sensor can be shown to have readings with a flat arrow (so effectively steady state) vs the Libre blood tests with variance of >15% over a few days, then they will replace it. As the manual states, when levels are changing rapidly, they tell you not to rely on it and to finger prick.

One offs, even if you are going low or high, happen, as the predictive algorithm struggles with exactly what is going on in high velocity cases.

In this case, I would recommend keeping a record over multiple tests and days and if you find that you are regularly exceeding 15% then call them up.
 
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noblehead

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It could have been a rapid drop as it was during my morning walk to work. I noticed that libre has a bit of a time lag but it was a bit funny for whole morning. I started a walk with levels of 12 rising to 13.8. Then dropping slowly to around 8. I tested only beacause suddenly I started to feel a bit dizzy. Libre showed over 6 but in fact I was below 4

That's what I'm saying @ewelina, I always walk my dog for an hour each evening and try and leave a 90min gap from bolusing for my evening meal, on the first full week of using the Libre I came back one evening and felt low, checked on my pump and was 3.5 but a quick scan on the Libre said I was 6.1mmol/l, however when I scanned the sensor around 20 mins after it was reading 3.8 so it wasn't far away.

So if you've got active IOB you need to double check on a separate bg meter or using the Libre bg meter itself, don't trust it to make judgements on whether to treat a hypo or not.
 
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slip

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The other day I called Abbot regarding a sensor that had been 'wonky' the previous day and at breakfast, I didn't call them until late morning, and actually did my 2nd scan just before I picked up the phone only to see a flat line LO graph pretty much since just after breakfast, a blood test (using the Libre itself) showed I was 4 point something.

Anyhow during the call the call handler asked when I last ate and injected, so 3-4hrs ago which pretty much ruled out any 'high velocity' changes being the cause - so I think calling before you're about to eat is a good idea, I know I will if I have to again.

Just for information, they will ask you to scan and blood test at the start of the call and then go through their usual procedure of checking serial numbers & other info etc and then about 10mins after the initial blood test get you to scan again to see if the scan is within the tolerance's allowed and time lag covered.
 
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tim2000s

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Just for information, they will ask you to scan and blood test at the start of the call and then go through their usual procedure of checking serial numbers & other info etc and then about 10mins after the initial blood test get you to scan again to see if the scan is within the tolerance's allowed and time lag covered.
Typically they only do this if you haven't many records of mismatches. So far, I've kept a record of five or so occurrences of mismatches and not been asked to do this.

They also don't accept results which don't have a flat arrow for comparison as being valid, for obvious reasons.
 
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AndBreathe

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Typically they only do this if you haven't many records of mismatches. So far, I've kept a record of five or so occurrences of mismatches and not been asked to do this.

They also don't accept results which don't have a flat arrow for comparison as being valid, for obvious reasons.

The way my bloods meander, I rarely see the up/down arrows, so when I do, this is often a warning sign to me that the sensor could be a bit off. I had such an instance with this sensor whereby it was saying 2.9, downward arrow, but I was actually 4.6. Moments later, it scanned 3.0, flat arrow.

I've found them pretty balanced in their approach, but I do absolutely agree it makes sense to call with data prepared so that the case can be put succinctly, with time/score examples to hand, rather than, "it's been low....."
 
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