Dexcom G6 input

Has anyone else been having a problem with their G6 sensors for 1 not lasting the full 10 days, over the past few months sensors have not been lasting over 6 or 7 days! Also has anyone been getting off readings? I have been getting false lows…just wondering if anyone else is having the same problem.

Hi @Dee314 . I don’t know if you’ve checked out the topic on Compression Lows - that could explain some of your readings.
Be sure to request replacements - Dexcom will send a new sensor of they don’t last 10 days.

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I just had one that was off and was just replaced. Some of my readings were really far off and would say I was dropping quick when I tested and was higher than the value or even that I was high and my blood sugar would be normal. If you haven’t already, I’d call support. They had me calibrate the first time but then replaced it on the second call no problem. They do document a bunch of stuff too so the sooner you call the better just so you can get a replacement.

@Dee314 ,

Dee, here is the comment about COMPRESSION LOWs I wrote earlier. I have worked on improving and fact checking everything in the comment. So, here is the new and improved comment:

Compression Low

BACKGROUND : Compression lows are caused by the person’s body pressing against the mattress, pinning the CGM sensor/transmitter (CGM) between the person’s body and the mattress during sleep. First, the interstitial fluid (IF) is the fluid around body cells. Most of the time IF is exchanged with fluids in the blood vessels. During this exchange, IF glucose is enriched and cellular waste products are removed from the IF all over the body.

THE PROBLEM : When a person is in sound sleep and is mashing the CGM into the mattress, the IF is also mashed. It is this mashing or compressing of the IF that causes the IF not to exchange as it normally does. Since the cells around the CGM sensor wire continue to consume (eat) the glucose available in the compressed area around the sensor wire the glucose in the area drops.

OBSERVATION : It is this low reading in the CGM data that is usually seen as a nearly level data graph and then a sudden drop of the glucose level. Because it is a low brought about by the pressure on the CGM, the term COMPRESSION LOW has been offered in pumping circles. Because the Compression Low is a low glucose only in the area of the CGM, a finger stick performed in response to a LOW alarm will show NORMAL. The variation between the finger stick and the CGM data leads to frustration and bewilderment, believing technology is the source of the error.

The next observation is the blood sugar measured by the CGM will return to a value near where the CGM line was before the drop in CGM value. The near level line, the drop & alarm, the finger stick of different reading, and the return to the near pre-alarm value is the full picture of the COMPRESSION LOW.

Here is a link to Susceptibility of Interstitial Continuous Glucose Monitor Performance to Sleeping Position

Not so much for the last couple of months. issues with 2 of those but they started on day 8 or 9 and I either replaced it or waited for hours for it to resume and it picked back up. Actually these latest sensors are the only ones I haven’t had drop outs with.
Reaction to the adhesive I have had.

Recently I have had several sensors with wildly off readings especially from the very beginning. In the past we have been told not to calibrate and the sensor will become more accurate but I talked with Dexcom and they said to go ahead and calibrate until you get it synced with your fingersticks and if this does not work they will of course send replacement. The support person I talk to at Dexcom technical support said this can be due to the trauma to the tissue at the time of insertion. The frustrating part can be that blood glucose meters can be 15% off of a true lab value or more with the less reliable meters. So even your very best meters can be 15% off.

Hi @Grumpy . I’ve occasionally - but rarely - get dropouts with my G6 and my former G5. The — showed on my screen for some mysterious reason. When I called tech support they told me to wait 3 hours and call back - I don’t knew if that matches your definition of “several” but they gave me a definite number.
In my case when I change out the sensor I find I “hit a bleeder”. If it bled a lot right away and I didn’t notice (I place a shield over it and tape over that so I don’t see it) it doesn’t even warm up correctly; but there have been times I’ve gotten them later in the game - perhaps bathing drew out more blood, I don’t know. Anyway, for some people that could be a reason for the “Dexcom dashes.” I now wait a bit after insertion to see if I get any blood. I find that unless it’s profuse I still get my readings and they’re good.

Dorie @wadawabbit , it is very easy to know when a “sensor error” has reached the three-hour point.
A large, bright “stop sign” spears on on the app screen and says “Replace Sensor Now”.

Hi Patricia @Pmaddix , what the Dexcom Rep told you fits well with my thinking. One additional suggestion I will make is try not to calibrate if/when the direction arrow is anything other than horizontal. Also be aware that for most people, the Dexcom Sensor reading lags about 15 minute behind a finger-stick readings.

About a half dozen years ago, the US FDA banned sales of glucose meters that are NOT tested to give readings within 15% or 15 mg of accuracy; and, that G6 sensors have a MARD rating of 6.

Thanks - I was told to wait 3 hours for the dashes to clear but a reading had usually replaced the dashes within 2 hours most of the time.

Like @Dennis said, you know when a sensor fails. I had several last year. It seems most people have a very good experience with the G6 but some of us don’t. I had many good years with the g5 so I’m very familiar with the dexcom system and can’t explain why the g6 isn’t working as reliably as the g5 did for me.
I wanted @Dee314 to know that not everybody has a great experience with the g6. In fact, when my current transmitters expire, I’m trying the Libre or Medtronic system on a long term basis. My short term tests with the libre were pretty good.

With the G5 you were supposed to avoid using acetaminophen painkillers. The G6 does not have that restriction but when I hear of issues I always wonder if there is some other substance affecting the readings. Or perhaps it’s related to body chemistry.
Thank goodness for you that the transmitters have just a 3 month lifespan. I hope you have great long term great with the Libre.

They told us to avoid acetaminophen still, even with the G6. Dunno if that’s right, wrong, or out of an abundance of caution in the face of insufficient data, though — just sharing what we were told.

Yes we were told if we use any acetaminophen to finger stick to compare to what the G6 is reading, I personally haven’t had any trouble that route, just her sensors not last the 10 days, just very frustrating, wasn’t sure if it was just me or if anyone else was having the same problem, I really rely on the G6 on school days. Her last sensor was giving off quite a few false lows.

I thought it was advertised as ok to use with acetaminophen. Well hmmph!!

Hi Dee, yes I’ve had at least the last 4 of 5 G6 sensors working well until about 8 or 9 days, and then I start receiving lost signal messages and I’ll be offline for 3 hours. Very frustrating. DexCom is good about sending replacements. Most reps tell me it’s probably because the sensor shifted in my body. Not sure I agree but they had no other explanation.

So frustrating! And maddening. I hope they are able to find a solution soon - replacements are well good and fine but you would think it would be more economical to avoid them as much as possible.

Hi Ann @NavyGal83 , are you talking about “Signal Loss” because something is interrupting wave signals between the transmitter and receiver [displayed on the receiver as a red martini glass], or are you receiving a “Sensor Error” message accompanied by " — " [three dashes]. Two very different conditions with the only common item being that you do not receive glucose readings or trend arrows, and both conditions can be frustrating.

The Sensor Error can be, and often is caused by a slight shift in the way the wire is embedded in our bodies. This condition occurs in people who do not have any “extra” weight; it occurs too often for my comfort. In discussing this extensively with both Dexcom and Tandem technicians, I received a suggestions that I only implant the G6 in an area where I can “pinch an inch” - for me, not many locations.

Yes G6 sensors frequently do not last the 10 days. Dexcom will send you a replacement sensor readily. Just a pain. I usually do the math. If sensor lasts 4 days and new one gives me another 6 or 7 then I’m good. But if falls below that 10 mark, just keep requesting replacements. I have talked to different technicians and reps on why the sensors seem to have become much less reliable and have not got a good answer. Considering trial of Free Style Libre. The Libre 3 should be coming out in future with same characteristics as G6, ie. sends alerts etc. But for now will just keep with the G6 and replace sensors when needed.

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No, I’ve never had a sensor quit early, though I quite often have readings that are as much as 40 pts high or low when compared to a blood test. On the t-slim pump it’s easy to adjust to bring then G6 back into reality.