FUDiabetes

Libre sensor...alternate sites?

freestyle-libre

#1

I might be between CGM’s later this month while I work to have all my prior authorizations and red tape for the Eversense squared away with my rinky dink health insurer. I am considering using the Freestyle Libre for a few months to tide me over into 2019 because I have stockpiled some LIbre 10 day sensors and would like to use them up.

Question: Has anyone had success with alternate sites for the Libre sensor? I tried the Libre earlier this year and was generally happy with durability and accuracy but discovered that I can’t get a reading through my hockey pads on the upper arm. I’d like to try belly placement or lower side abdomen but understand these alternate sites are strongly discouraged by Abbott.


#2

The only non-arm site I tried with the Libre was on my upper thigh, and the accuracy was not good at all. Like, Libre saying I’m 200 and fingerstick saying I’m 70 level of bad. I tried this site twice, for some reason, and both times it was problematic, it seemed like no matter how much I calibrated (in Spike) the sensor values would drift away from where I actually was.

I’ve never tried the abdomen but I hope someone else has more encouraging experiences with alternate site placement with the Libre!


#3

I haven’t used an alternate site, but I’ve heard thighs are a pretty good spot for some (but obviously not everyone). I haven’t tried it because my son would easily knock it off when I’m holding him…


#4

Wow. That’s a pretty bad discrepancy.


#5

So far I’ve tried the suggested site (back of the arm)

The lower thigh

The top / inner arm

And the opposite side top / inner arm

And, for me at least, the inner arm is the undeniable favorite, mostly because it’s simply easier to scan/access with my cellphone reader. The factory scanner is a lot more tolerant of placement. The cellphone needs to be relatively centered in the right position to complete a successful scan, hence the preference. It’s just an easier location to read, for me at least.

Although I’ve been fortunate that my sensors have all been relatively accurate, I attribute that less to the location and more to the app/software that I am using, since both 3rd party apps that I use are much more accurate than the factory scanner, which does seem to become more accurate over time as there is more sensor data to use to average out.
The apps I use will both self calibrate with the addition of manual fingerstick blood glucose entries, and will also provide improved reading accuracy over time.

I will say that I find the sensors more than accurate enough to calculate meal, extended, and correction bolus dosage, which, I will freely admit, I was quite skeptical about when first starting up with them. I’ve settled into a daily routine of one morning fingerstick reading to start out my day (fasting glucose) and another one just before bedtime, to get the most accurate reading to base any potential correction bolus needs at bedtime.

I also find that the SimPatch (tan/flesh) can and will last for the entire 14 day sensor life, although it may need a bit of trimming here and there along the way.
The Rocktape (green/black), on the other hand, rarely lasts more than 5 days, so I need 3 patches for the same 14 day sensor life vs using the SimPatch. The Rocktape is also more troublesome to apply, since the sensor must pass through the opening instead of being covered over by the SimPatch.

Due to it’s extended longevity, the SimPatch is substantialy more cost effective since both have the same approximate unit cost.

On several of the Libre Facebook groups, both US and Worldwide groups, there are reports of studies that list the stomache/belly area as being the least accurate location of all. There is also anectdotal enthusiasm for the upper breast area from many female users. Not to mention some pondering as to the potential accuracy for use on a similar “man boob” location. The verdict appears to still be out on that one!


#6

Thanks, @DaveJ! Venturing out from the back of my arm tonight— Only to the side of the arm, but you know the saying… A journey to the other side of your body starts at the side of your arm. :grin:


#7

So… lost that sensor during warm up. :confused: It’s the first one I’ve lost like that, and I’m not sure if it had anything to do with the change of location or not. It may have been coincidence, but I didn’t lose it until after I attached my MiaoMiao, so maybe it wasn’t the location at all. Another unsolved mystery.

Either way, I’m doing back of the arm for this one so I can get me some Dexcom/Guardian/Libre numbers for comparison, and then I’m going lower, inner thigh… maybe. :grin:


#8

Wait, @DaveJ— lower inner or outer thigh??


#9

I’ve done both, actually.
Inner seems to be more convenient, but also less accurate.###
Outer was more difficult to reach, but a lot more accurate.
But with the Libre, there is no expectation that these accuracy results are repeatable on the same person, much less with someone else entirely.
It is, by and large, a personal trial and error process.
The inner arm is still my preferred location, since it gives me the best combination of convenience and accuracy. That being said, not so sure how the added bulk of the MM would play into that experience, since I have deliberately held off on even considering one until the incompatibility issues with the new US 14 day sensors is resolved.
NewLibreThigh_web
Libre Inner Thigh

### NOTE: This particular sensor did not get the customary 12-24hr pre-activation insertion warm up period