The 22nd of June is my 2nd sensor setup

Good morning my darling diabetics. I am nearing the end of my OG Dexcom G6 sensor, and on the 22nd I continue my Dexcom journey! I just wanted to touch base with everyone, being there are 2 valid options for setting up new sensors that have been proven tried and true by you brilliant individuals. So I am back to the drawing board.

I have had a decent experience with code and never calibrating however… I have noticed times where it says I’m 116, but really I’m 95 mg/dl. Though this is within the accuracy range of (I believe it’s 20% average), it does prove a BIT nerve-racking when it’s a difference between 200m/d and my meter is reading 177.

I have not tried no code and calibrating and I was just wondering what everyone’s experience is with the difference ratio between CGM readings and fingerstick readings. I know I have read mixed reviews on both methods. So feel free to share your suggestions, as I am swapping sensors in 2 days!

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For me that difference doesn’t matter at all, because it doesn’t change what I’ll do. Whether the real BG is 200 or 177, I’ll take a correction dose of insulin to bring it down to a good level. Whether it’s 116 or 95, if the CGM graph is relatively level there’s nothing that I need to do. If I recently took a bolus and the CGM shows 95 and plummeting, I’m going to keep a close watch on the graph, and probably eat some relatively fast carbs soon.

As for the question of calibrate or not, that’s a personal choice. For me I use the code and never calibrate and rarely fingerstick, because managing my BG is already too much work, so why add even more? But that’s only because for me the Dex is sufficiently accurate that I can rely on it for decisions about insulin and carbs. And anyway, if the Dex says 116 and the fingerstick says 95, how do you know which one is actually right? We’re naturally inclined to believe the fingerstick is the true number, but that’s not necessarily so. What really matters, whether it’s 116 or 95, is whether the graph shows a BG accelerating upwards, or plummeting, or staying more or less level. That’s what tells us what we need to do.

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There will often be a lag like that so if you go with calibrating it’s important to do it when the CGM reading is fairly level for at least 20 minutes or so, in my experience.

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Good to know! I may just keep coding and not calibrating, it has shown to work decent as far as accuracy is concerned. Going based off what @bkh said, I’m certain this way is working for me and currently only have 2 sensors. Probably follow the philosophy of “if it ain’t broke, don’t fix it” :laughing:

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Absolutely :100: percent.

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I always use the code but I got so conditioned to fingersticks that I still do one a day (most days) in the morning when I wake up. I will calibrate if the two readings are vastly different. I don’t really care which reading is “correct” but I like them to be similar. I calibrate maybe once a week.

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Remember that the first day readings are often out of whack, and try not to calibrate for the first 12 hours or so.
The solution that many of us have found is to presoak the sensor.
I insert the new sensor the night before, but I don’t change anything.
In the morning I stop the previous sensor, remove the transmitter from it and wait 10-15 minutes, then put it in the new sensor that I put in the night before. Start that one up and have a MUCH more stable first 12/24 hours!
Soaking the sensor helps with getting the system to be a lot more stable.
I am one of those that uses the code, and RARELY fingersticks. I use the Tandem X2 pump and it changes my basal automatically according to my dexcom reading, so I really do trust it! Not everyone is fortunate to have great readings from the Dexcom, but a lot of us do. Hopefully you will as well.
Btw, some people will presoak for 2 hours, 12 hours, 24 hours, etc. Whatever works best for YOU. I found that 12 hours was pretty much my point of diminished returns for soaking a sensor.

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This is such a smart idea and I can’t believe I haven’t thought of it sooner! I might have to try this out and see. Ironically enough, I installed my first sensor around 11am and by 4-5pm the numbers were so accurate I was surprised. If I pre-soak my sensor though, I would have to sleep on my back because I am switching sides of my abdomen and so both sides would be off limits to sleep on :laughing:

I know the suggested spot for placement is your abdomen, I put feelers out in the threads here and a lot of people wear them elsewhere. I’m going to see if I can get a hold of aspn pharmacies today though - as someone was gracious enough on here to mail me out 2 sensors for the time being. I am in pharmacy-medical insurance limbo with my Dexcom coverage. The last I spoke to aspn, they were attempting to find a place to cover it through my UMR (commercial insurance, PPO policy through my employer) and tbh I’m a little worried there’s going to be a denial on their end too. It would be nice to get some word back from them, even if there’s no progress… just to know they’re still working on it would be helpful. If all else fails, I will reach out to my Endo so they can send a medical necessity letter in regards to my hypo-unawareness.

But it’s good to have all of this information at my disposal. All of you have been so helpful! :slightly_smiling_face:

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No reason you can’t sleep on the new sensor, as it isn’t doing any real readings. I never bother worrying about this part.
As for placement, I would concentrate on making sure you get the hang of things, and how dexcom works with you. Then start exploring different locations.
If you don’t have base data to compare to, you won’t be able to say the arm or leg locations are as good as the belly.

And I found that whether I soak for 12 or 24 hours, my initial readings are about the same. Not much difference. Leaps and bounds better than if I have to swap out the sensor without a presoak (like I accidently ripped it off, or forgot to presoak the previous sensor.)

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Truth be told I am a little nervous to take this old sensor off. Idk what it’s going to look like underneath :laughing:

I had a faulty initial sensor that I removed within 5-6 hours of placing on me and the adhesive was a b*tch to pull off, not to mention the little hole that was left behind from the sensor needle was decent. I’m going to try not to think about this until tomorrow lmao.

I wear the sensor on my abdomen and sometimes sleep on my abdomen. It generally works ok; only sometimes gives a pressure low and then I just shift my position. I’ve started presoaking in the early evening and starting the sensor later in the evening. By the next morning the CGM usually is working well.

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There’s no discomfort when you lay it? I have been avoiding this haha. :laughing:

None at all.

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I have no discomfort sleeping on mine.
I have tried other locations that had interference with muscle tissue, and those I noticed if I slept on it.
But, for presoaking it, it won’t make a difference either way, as it isn’t sending any information, just soaking in your interstitial fluid.

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While presoaking probably doesn’t make a significant difference in sensor lifespan, it is at least technically incorrect to say that it won’t have any effect on the CGM probe. Even if your CGM probe is “just soaking in your interstitial fluid”, your body will still be trying to “destroy” it.

Unless the tech for CGM has changed significantly over the last 6 to 10 years … I don’t believe it has, but I have no way of knowing for sure … the reason your CGM degrades over time is not primarily a result of use but instead your body’s immune system. If you place any foreign object inside your body, the human body will try to “break it down” to get rid of it. This happens to a CGM sensor probe.

The glucose measuring tech which I believe Dexcom & Medtronic’s CGM sensors are (still) based on is enzymatic. In that sense it is technically reusable. It doesn’t fade away as it is used. Instead, the primary source of why a CGM probe degrades over time is more directly a result of a body’s immune response to a foreign object.

My understanding is that the proprietary fabrication secrets the CGM competitors focus on protecting are the very complex methods used to allow the CGM probe to be both permeable … to allow your interstitial glucose to reach it … while at the same time remain as impervious as they can make it to our body’s attempts to destroy and expel it.

The basic enzymatic reaction which the popular CGM sensors use to measure glucose are apparently well known. You can find some limited discussion about it by carefully Googling about. What the CGM makers will never talk about, their “secret sauce” if you will, are the methods they use to protect the sensor probe from degradation from the immune system. Making a sensor last is the truly difficult part of making a successful CGM.

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You are definitely correct in that it does shorten the lifespan of the sensor probe itself.
That being said, we all act and react differently to these, and these sensors degrade at different rates for each of us.
For me, I always get 14 days out of mine, I could probably get 21 or more without issue, I just have too much issue with the newer adhesives not working, and I HATE using over patches, etc.
So, for people like me, it will never shorten the lifespan enough to make a difference within the time frame I use it for.
Other people definitely have issues making the sensor live past day 7-9. Those people I would not recommend doing anything more than a 2 hour soak.

These were designed to last 14 days, but only given the greenlight for 10 days. And while some people have issues not lasting 7 days, I think most people have good luck, and could extend there sensors a couple times over without issue.

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Btw, before they changed the darn adhesives, I normally used the same sensor for 14 to 21 days, and it wasn’t out of the normal for them to last 28 days or longer.
Yes, I used Skintac (still do,) but they just stayed ON a lot longer than they do now!

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I’ve noticed this sensor adhesive is not in the same place I inserted it, as on the top layer I have a line of grey sticky from where the adhesive initially stuck on. Waterproof my :peach: :laughing:

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You are correct that both are using an enzymatic approach to sensing glucose, however in my experience studying enzyme sensors, the primary reason they degrade is body temperature. Unless you find a way to constrict the movement of the enzyme body temperature allows a significant amount of the enzyme to denature. The body’s foreign body reaction is not helpful either, but this is manageable by using coatings. We once put an enzyme into a sol-gel and got it to last 4 months at body temperature. The control sensor was dead in less than a month. I think the primary reason that sensors stopped lasting 30 days like the old G5’s is that they made a manufacturing improvement and reduced the amount of enzyme they deposit in the sensor.

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If the skin was slack when you put on the sensor, normal movement will stretch the skin out from under the sensor a bit. It doesn’t seem to matter in my case. If it bothers you, arch back a bit to slightly stretch the skin when inserting the sensor in your abdomen.

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