You'll be wanting an update on my experiences with the Dexcom 7+ CGMS. I can only describe it as a rollercoaster, technologically and emotionally.
In my last post, two days in, I loved it. It was the answer to all my prayers, working perfectly and giving me confidence.
On Day 5, we were going to visit friends (it was 2 days after Christmas Day) and I was happy that I would not be worried about my blood sugars because I could see what they were doing at the touch of a button. Yeah, THAT worked!! On the drive over, the display on the Dex started to show ??? which means that the receiver is not interpreting the results sent by the transmitter. In the manual it said this can sometimes happen and to leave it alone and it will come back.
I had ??? for a total of 10 HOURS!!! It totally ruined my day because my anxiety levels went through the roof. We had a pub lunch, never a good idea for me, and I had to do finger pricks all day as per usual.
I rang the support guys and neither of them could explain it. The Dex came back to life overnight and was fine, but the next morning ??? came back again as soon as I got up. Another disruptive day, more phone calls, still no idea. I left the sensor in but by day 7 it was just silly. I changed it.
I had the same start up problems as the first sensor, with a 10-ish hour delay before it started reading properly, but then it was ok. On Day 7 ??? started again. The adhesive had peeled up and none of the tapes I tried would stick it down.
I have concluded after 3-4 sensors that the problem is that once the adhesive starts to give up, the sensor wire moves about under my skin and cannot get readings. I think it has to stay perfectly still to be able to get an electrical signal from the interstitial fluid. After asking lots of questions on TuDiabetes I got some suggestions for adhesives to use on the skin. However these did not prove easy to find here in the UK. I did manage to find Skin Tac wipes on the internet from a company who appears to sell them for the purpose of sticking false boobs on!! Anyway, those appear to help if I use them on the skin before putting in a new sensor. I also got Tegaderm patches from ebay which I cut a hole in so as not to cover the transmitter, and then put over the whole thing. They are large but mostly invisible and very sticky. And thin so they fit the contours of the skin. My 4th sensor lasted 11 days, which was great.
The 5th sensor which is in at the moment is not so great. I put it in on Sunday so that it would be settled and working well for an overnight trip to London on Wednesday. I used Skin Tac and Tegaderm to secure it so there was no chance of movement. Ok, it didn't move. But its not right either. On Wednesday morning it gave me a reading of 6.5 mmol/l (117) but my meter said 11.9 (214). The trend arrows kept disappearing and the results were all a bit wierd. I was going to an award ceremony and was anxious all night because I didn't feel I could trust the Dex.
It is now Friday morning and I still have the same sensor in as it is working. The readings are about 1-2 mmol/l off constantly but I can live with that until I change it.
When it is working well, I am happy and feel more confident at lowering blood sugars. As soon as it doesn't play fair, my anxiety goes up and my mood crashes.
At the moment I still want it to work for me. I am going to keep using it and see how things go. On December 18th my HbA1c was 10.3, and on January 27th it was 10.2. Hmmm, no big difference but hopefully by the next one in March, I can have improved on that.