My daughter (8) has had her Dexcom G4 since November 2012 and generally the sensors last about 3 days before they stop working (question marks) and eventually fail. Very rarely will we have a sensor that lasts the full week. I have been very careful about how the sensors are inserted and spoken rather extensively and frequently with Dexcom about this problem. The best that they can figure (and me as well) is that the poor sensor performance is because my daughter is very thin (~5th percentile in weight) and there's simply not enough of a fatty layer for the sensor to reside in.
Does anybody else have this problem (regardless of whether it's related to weight)? Does anybody have any suggestions of what I can do differently to get better performance out of these sensors?
Hi Firehead Wondering how you were successful in attaining an rx for the dexcom from your MD. Just posted a blog looking for a parent(s) that may have been successful. More or less it seems that <18 and no "significant" hypo's then MD's really arent into rx'ing it. If you dont mind sharing.... I think it would be so helpful for my son to have one for daily feedback.
My 8 yr old daughter is in the 40% for height and weight. We find that we have problems with the sensor when it is on her belly. It tends to fail alot for whatever reason and no matter how many times we restart it it does not last the full week. Since we started putting the sensor on the back of her arms we find that not only does it work the entire week but we can usually get at least 10-12 days.
Patricia - my daughter's endocrinologist is very enthusiastic about CGMs and was very happy to write a prescription for the Dexcom G4. If my doctor didn't find it useful, well, I'd probably find another doctor. Hopefully you can find somebody who is okay prescribing it. Good luck!
Piki - That's great you've had luck with alternative sites. I have tried the back of my daughter's arms several times and it seems to be pretty much the same as the abdomen.
Being "too thin" seems a silly answer to me given that there's pictures all over the internet of small kids with sensors.... arms and butts seem to be the best spots for young kids so it might just be all about alternate site choices (which Dex will not suggest, because they aren't officially approved by the FDA).
Skye - I have tried the arms with my daughter, but I get the same result (sensors last on average 3 days). We have not been able to try her rear yet, but that's next on the list. I think Dexcom's rationale is that if you're really thin, the subcutaneous layer where the sensor is supposed to reside isn't very big, so it's easy for the sensor to enter the muscle and/or there is not enough interstitial fluid to get accurate readings.
I had this happen a few times when I started with the G4, but haven't had any problems since. I am very skinny (6'1" 130 lbs 2% body fat prior to diagnosis - was down to 109lbs when diagnosed)and have a lot of issues finding good sites for the CGM and pump. For the most part, I have stuck to the abdomen because there aren't many other places where I have enough "cushion". For my pump, I use an insertion set with an actual needle and I usually use my lower back or upper buttocks because that is where I have a little bit of fat.
I agree with the recommendations to use alternative sites. I am a thin woman and I have been most successful placing the sensor on my upper arm, in a spot where there is flesh to pinch.
Thanks GeekDaddy. I have had a CDE come out to help with placement. We looked around a bit for the areas with the most fat, but sadly haven't been able to get a better result yet.
Helmut, it varies a little, but after a couple of days, it typically stops reporting a BG value for periods of time (displays ???) and then either fails with a Sensor Failed message, or it will stay on ??? (for many days at a time if I don't manually stop the sensor).
??? is often caused by dehydration. Conduct a science experiment. Ask your daughter to drink eight 8 oz glasses of water per day for a week. I hope she is up for a little experimentation.
When I was leaner I had similar issues (and it hurt,too) on my stomach sites. They suggested leaning the inserter back/down a bit so it wouldn’t slide in as deep.
Well, great minds think alike. I thought about that too and had her drink a lot of water a few sensors ago and sadly got the same performance. It a good reminder though that she needs to drink more water!
One other idea: I saw ??? only once with the Dexcom Gen4 (9 months). It happened to coincide with the only time when I did not clean the transmitter contacts with alcohol.
