Note: I have reviewed the existing posts I found on the topic, as well as the extensive “Dexcom Adhesive” thread. But I may have missed some threads thru poor google-fu?
My T1D son, who is 12, has been on a Dexcom G5 for a few weeks. He swims competitively. We stopped his swimming for a fortnight to test the G5. We were able to get it to stick for 10+ days by cleaning his skin with alcohol, and using Skin-Tac, then the sensor patch.
However, the patch adhesive is not working well in the swimming pool with his frequent practice sessions, even with Skin-Tac.
We reviewed the forum recommendations. We tried to add Hypafix strips (with and without Skin-Tac under it) on the edges on the patch when they started to lift: we set the strips in the shape of a rectangle overlapping the Dexcom patch up to the plastic sides on the sensor. But we were never able to get the Hypafix to stick well to the top of the Dexcom patch (not the transmitter, of course), although some apparently are able to do so. For us, Hypafix works better on the skin when used with Skin-Tac, but refuses to stick to the Dexcom patch either way.
I have already obtained some Tegaderm and some GrifGrips. But, before experimenting further with either (or Hypafix), I am wondering if some who are successful at it might be willing to share what works best for them, specifically for frequent swimming. I am not sure if very old threads are reliable on this topic, because it is not clear to me if adhesive formulations have remained the same over multiple years at Dexcom.
Thanks for your help! I will be sure to share what works for us once we have found a solution.
After Skin Tac (or IV Prep), then sensor (I had mistakenly said Pod), then Opsite Flexifix with a window cut out for the transmitter. TBH, with Dexcom sensors, we usually skip the Skin Tac/IV Prep and just use Opsite Flexifix on top. We do use Skin Tac/IV Prep under Pods, however.
I use skin tac, then Pod, then Tegaderm with window cut out for the transmitter. At the end of two weeks I have to use quite a bit of uni-solve because it’s still so stuck to his skin quite firmly. But he doesn’t swim being only 2, so not sure how he would perform in water all the time.
Do you actually use Opsite for frequent swimming, or for sensor longevity in general without frequent swimming?
I am asking a bit insistently because it doesn’t seem that general solutions for adhesive longevity translate well to the pool. I am hoping to find solutions that will work for daily swimming practices for the duration of the sensor -or longer:-).
My daughter practically lives in the bathtub this time of year, and she’s in and out of swimming pools for a good part of the summer. We lost one sensor last summer when she was full-out wrestling with a guy in a pool. Other than that, those sensors pretty much stay put. Whenever one has come off prematurely, it seems to be from becoming mechanically dislodged (as opposed to from water exposure).
Are you allowing the Skin Tac to dry a bit before applying the Hypafix? My daughter has used Hypafix since her first Dexcom 6 1/2 yrs ago & we haven’t had any problems. We cut a piece slightly larger than the Dex adhesive patch (we use 4" Hypafix & cut out the center for the transmitter) & round the corners. Opsite sticks better & for longer, but it caused a horrible rash every time she used it. My daughter swims every day, tear round.
No, we didn’t - this might be our problem? The Hypafix adhered to the skin, but not at all to the sensor patch, either with or without Skin-Tac.
Are you saying that, when you put Skin-Tac on the skin and the Dexcom patch, wait for it to dry a bit, then apply the Hypafix, it sticks well to the dexcom patch? If so, that would be great. I like the idea of using the Hypafix, because I feel comfortable removing it easily from the sensor patch - so I figure I can make the sensor last longer by putting a new layer of hypafix after having removed the previous one.
How long do you wait to let the Skin-Tac dry, normally, before applying the Hypafix?
Also, do you change the Hypafix over several times? My son also swims pretty much daily - I am curious what your average sensor life is?
I apply 2-3 coats of Skin Tac to the skin in an oval shape & let it get tacky between each coat. It takes about 5 minutes. I insert the sensor & immediately cover with Hypafix. There’s enough Skin Tac to seep through the adhesive pad & help hold the Hypafix in place. We change out the Hypafix every 3-4 days. Rounding the corners seems to help keep it from peeling up. We almost always get 3 weeks out of a sensor. For us, the key to long life is keeping the sensor from moving around, which is why we tape from the start.
Opsite definitely sticks better, but I wouldn’t want to try to change it out. It’s just too rough on her skin.
Our issue right now isn’t the adhesive, it’s that, after about 10 days, the sensor starts to go in and out frequently. Anyone knows what could be causing that? Our adhesive has (and can) last well beyond 2 weeks, but after about the 10 - 12 day range, we get “question marks” for large spans of time (30 minutes - 2 hours sometimes)…which sometimes turns into an hour glass…which eventually turns into good numbers again. But, when we see these question marks start happening, we know we’ll need to change it out soon. That’s kind of our indicator for when to change it out. Anyone else have this problem?
This is a 7-day product? Remember wearing a CGM is not contest to see how long you can keep it going. For me, I am satisfied at 7 days, at 10 days I am thrilled at 14 very excited. Yes, I have gotten more but remember this is a 7-day product. We do not expect a tank of gas to last 1,000 miles just because a solar powered car can go 100 miles on a gallon of gas.
Just guessing based on 6+ yrs experience with Dexcom.
The ???s mean the data can’t be interpreted by the system. In our experience that can be caused by:
A bad sensor --not as likely as it was with older Dex generations, but still happens occasionally.
Calibrating errors–bad timing/too many/not enough. After a restart, we have to calibrate several times the first day. If we don’t, both the accuracy & sensor life suffer. When we start seeing ???s or the hour glass, we give it an hour or so then restart 1 time before giving up.
Multiple swings in BG–more variability=shorter sensor life & less accuracy.
Movement of the sensor element --much more likely with an active child.
Location–pressure on the sensor during sleep, sitting etc causes movement in the element.
Immune response to the sensor element/erosion of the enzyme coating on the element. It is a foreign object after all.
While most users have excellent results with Dexcom, there are quite a few for whom it just doesn’t work as well. I know several users who were totally frustrated by the Dexcom, but they have incredible results with Medtronic. YDMV applies to device success as well.
My daughter consistently got 3-4 weeks out of the 7+ sensors. My spreadsheet showed the average sensor life was 26 days. Unlike some, we had excellent accuracy with the 7+, likely due in large part to Skin Tac/taping from day 1, & our early use of the techniques now known as Sugar Surfing. Enter the G4. We saw accuracy drop significantly, & sensors rarely last beyond 2 weeks. I believe at least part of the problem is caused by the heavier weight of the G4 transmitter, which makes it much harder to limit movement if the element & also causes more issues with keeping the sensor attached.
Due to Dexcom staffing shortages & insurance changes, we had an unplanned break for almost 6 months this year. I had hoped the break might help with any immune-related issues & we are definitely seeing an improvement, although still not the accuracy or sensor life we saw with the 7+. We chose not to upgrade to the G5.
I am reporting on our first fix, which seems to be working so far, although (1) I ordered some Opsite Flexifix to emulate rgcainmd’s MO, as (2) we also intend to try Hypafix with Skin-Tac in several layers left to dry, as per tiaE.
I had some Tegaderm at hand (that was before I had ordered Opsite, and understood the multi-layer Skin-Tac MO with Hypafix), so that’s what I used for the first trial.
We had applied the patch with some Skin-Tac. When it started peeling a bit after 4 days, we cut off the peeled off areas, cleaned with alcohol, then put some tegaderm over the whole patch area. We did it again a few days later. It’s still holding. It looks like trimming, cleaning then reapplying Tegaderm, as a process, works fine.
Next two sensors we will try Hypafix and Opsite to compare.
For our sons tegaderm, I’ve found that the INSIDE part of the taps stays firm past two weeks. The outsides peel away every time, but after I cut the majority of the part that’s peeled away, off, no more peels away and I don’t apply any additional Skin-tac.
The last two sensors, we used Hypafix (thanks @tiaE for the advice!) This is what we did and the results we got:
we applied 3 layers of Skin-Tac, letting it dry for a while every time.
After the last layer became tacky, we applied the Dexcom patch, then rubbed it hard with fingers for two minutes.
Then we applied 4 Hypafix strips in a rectangle around the dexcom patch, still over the Skin-Tac
The Hypafix remained in place for 4-5 days for all strips but one, after which we carefully removed them all, cleaned the adhesive with alcohol, reapplied Skin-Tac, waited for it to get tacky, the reapplied Hypafix strips. We wentt hrough the process twice, and were able to keep the sensor working for 2 full weeks before lossing reliability.
Advantage of Hypafix compared to Tegaderm: it’s easy to remove, and you don’t haev to worry about partial peels (you just take the strip off easily then reapply).
Disadvantage: each application of Hypafix did not last very long. The tegaderm lasted longer and lost adhesion in smaller areas only.
With Hypafix, we were able to keep sensors working 2 weeks one time, 13 days another. With Tegaderm, we were able to keep a sensor working for about 17 days. In both cases, the sensors were exposed to pool water for multiple practice sessions per week.
The Tegaderm definitely held better. But, as a process, the Hypafix did not seem to bring a signficiant drawback if you accept that you will need to re-apply it more often.
We plan on testing Griffgrip and Opsite over our next few sensors.
