Hi.
Sorry to hear you are having teething troubles (hopefully) with Libre and your BG is behaving erratically.
When you say "sensor error" are you getting the try again in 10 mins message with that or is it telling you to replace the sensor? The try again in 10 mins is usually when your levels are changing very fast and the Libre needs more data before it can reliably give a reading. Sometimes the signal just drops out if you are using the LibreView app on your phone and you need to scan to reconnect it. The sensor can need to be replaced if the filament got disturbed after application. This can happen by catching it on clothing or door frames or reaching into cupboards etc. I forgot which arm it was on and scrubbed mine loose in the shower a couple of times (I use exfoliating gloved when I shower and have a good scrub) but can happen when vigorously toweling dry too. I bought an elastic arm strap and this encures the adhesive gets a really good hold after application and protects against a lot of he catching on clothing but also acts as a visual reminder of which arm my Libre is on when I am in the shower. It consists of an elastic adjustable strap and a plastic 3D printed watch face which fits very snugly around the circumference of the sensor. They come in a variety of colours from skin tone neutrals to loud and proud neons. I got mine off ebay but I imagine there are options on Amazon too and no doubt other specialist sites.
Having a good application technique is also important and it takes time to find what works well. I apply mine after a shower. I towel dry and then blast the site with my hair drier to make sure it is absolutely clean and dry. I then go through the applicatio process, but I hold the applicator firmly against my arm for a count of 60 before I remove it. This is because the applicator never seems to come off cleanly and I have to wriggle it a bit to get it off and this extra time gives the adhesive a bit of bonding time with my skin before I start trying to get the applicator off and I gently wriggle it rather than just pull. I then apply pressure over the sensor, usually with a piece of toilet paper as there will usually be a spot of blood that oozes out of the centre hole. Then I put my arm strap on and I do this before I go to bed so that the sensor has all night to bond strongly with my skin before it is exposed to any knocks or snags. Placement is also important and you gradually find a spot where it is least likely to get caught on clothing or knocked on inanimate objects.
As regards your nocturnal hypo, did you double check it with a finger prick test? A sudden drop during the night is unusual because assuming you ate sufficiently early there should be no active bolus insulin in your system, so it would just be your basal insulin causing a nocturnal hypo and generally this will drop your levels gently. However, if you laid on the arm with the sensor, you get what is called a compression low where the Libre will show your levels dropping fast and the alarm will go off because you laid on the sensor. It is therefore important to double check any Libre low alarms with a finger prick before treating, particularly if it shows levels dropping fast, unless you feel noticeably hypo, and even more so if you are lying on that side when the low alarm goes off. If it was a genuine hypo, when did it happen and what time did you eat and inject your evening meal insulin and what were your levels like at bedtime? Have you been told to have a little snack if they are below a certain level (usually about 8 when you are first diagnosed) so that even if your basal insulin is a bit much, you should still have some wriggle room for levels to drop whilst you sleep.
If you are not already aware of compression lows with Libre and it's other limitation, there is a list of them in the thread I will link below. It is really important to understand it's limitations so that you don't get frustrated with it.
Moderator Note: This helpful reply was copied from another thread as it details some of the commonly experienced limitations of continuous glucose sensors. My blood sugar has been in perfect range for days now, but although I haven't changed anything, I'm starting to get very short periods of...
forum.diabetes.org.uk
Hope some of this information is of help. If it was a genuine hypo, well done for managing it. Sometimes the fear of them can be really debilitating but I found that having to face my fears and learning how well I could manage them, and figuring out why they happened and what I could do to try to prevent them gave me a lot of confidence with my diabetes management. I hope you gain that benefit from your unpleasant experience.
