Ever since I upgraded to the 505 firmware the numbers have been more accurate but sometimes much less smooth.
Here's several sleeping hours, fairly smooth:
Later that same day:
Anyone else see this? I’m wondering if perhaps some water got under the transmitter and caused this ragged line. This is only day three of this sensor.
Even the slight discontinuities in the smooth line seem more like post-505 update than prior.
Can anyone comment on the look of their post-505 lines versus the prior firmware version?
I have no pre-505 G4 experience for comparison. But if you're comparing nighttime to daytime numbers, it doesn't seem surprising to me that when there's more BG volatility during the day (due to various inputs, e.g. carbs, insulin, activity, stress, etc.), the lines also get more ragged.
Yes, I have seen this type of pattern more frequently since the 505 update, along with more variability in the arrow. I have seen the arrow go from pointing down and to the right, to suddenly pointing up and to the right. Also, I have seen the arrow pointing straight down/up and then move to pointing directly to the right, all within the space of 10 - 15 minutes.
I try and give it a little more time to "settle down" before reacting. Overall, I find the update to be significantly more accurate.
I am ready to throw my receiver out the window, it's been so inaccurate since I updated the software!! I'm really frustrated. Anyway, the only time I've seen readings like what you've shown was on the first couple days of a new session. Then they seemed to even out. I've also been getting a lost signal icon much more frequently. It could be that my transmitter is dying.
I agree, Mike. It does seem more accurate. I'm guessing that the 505 update tries to get the CGM line to react more quickly to changes. Like you, I've seen more arrow variability even when things are not that variable.
That has to be frustrating, Shelby! Have you tried switching for one sensor session to the freshest sensor stock you have and see if your results may be lot- or age-related? It could be affected by a weaker transmitter signal, too.
Have you talked with Dexcom customer service about your experience?
I saw this the first week I used the 505 software. I saw it occasionally on my old setup too, though arguably less "bouncy". In the past week though, and a very new sensor that I just put on last week, the lines have been extremely smooth. And the accuracy has seemed to improve incredibly. So it seems to me that some folks who mention that the sensors changed too might hold some reason. So do wait until your next sensor refill order before giving up on the 505 software.
Thanks for the comment, Scott. I wonder about quality variations in the sensors, too, but the quality of the tissue that it's embedded in probably plays a role as well. Next sensor, I'll try using one from my most current lot. I'm glad to read you're having such a great experience.
Some people consider a CGM and think they'll be bothered with obsessing over the data stream. I've learned so much useful information by monitoring the sensor data. In the end it makes life easier for me. I hope your experience remains good!
Yes, I saw that same scrambled pattern right after upgrading. Very weird. But then the next sensor was back closer to normal. In both cases I was mildly surprised by how the readings were more accurate. But then again, greater accuracy was the whole point of the upgrade :)
I find sensor performance extremely unreliable when I try to restart for a second week. First week is great and no "???" at all. Then I restart, and right away I get sporadic "???". I hear about folks getting four restarts out of their sensors, wildly different than my experience. One possible explanation is that I'm a swimmer, so the adhesive does seem to loosen up quite a bit, and I'm still trying to figure out an optimal way to keep it properly attached.
I'm going to insert the freshest sensor I have for the next session and see if my traces are smoother. I'm on day 8 of my current sensor and I've already had several ??? gaps in the first week. We'll see.
I've run 14-21 days on a few sensors pre-505. I suspect that keeping the sensor from shifting in the tissue helps with sensor longevity. Just a hypothesis.
I use tegaderm on my skin after I scrub it using a wash cloth with hot water and soap. The dex adhesive seems to stick OK for up to two weeks for me, but I'm not a swimmer.
I used to use the dex directly on the skin and then painting over the top of the adhesive bandage with Skin-Tac. I used this system when in Hawaii and going into the ocean or pool repeatedly. It did well. If it starts to peel, another coating of skin-tac over the bandage top restores adhesion.
I've also cut up 3M or Band-Aid "flexible fabric" bandages and used the tape portion to get several added days to my sensor session.
Five days ago, I used the freshest sensor in my stock (expires September 2015) and my lines are smooth again. So, the lumpiness I noted may be due to sensor age or it could be site related. I used my abdomen after a few month hiatus from stomach sites.
I don't know if this helps, but here's a day of 'high variability' data from last month where I wasn't aggressive enough in punching down the DP early in the day. You know how my numbers are, so theres a LOT of variability, compared to yours, but I wonder if there's an analogy. You can see a high incidence of rapidly rising and falling BG. You can see how the arrows aren't keeping up and there's a lot of sensor error in the column labeled '% diff'. That's measuring the error in the sensor. I wonder if you are having a bunch of mini-sized rapid increase and decreases. Your data is so finely tuned, I don't know. Maybe the new transmitter is more sensitive to changes. I think that's a good guess, but I don't know how that is calculated and I don't think they publish that. ???
I suspect that your sorta 'ping-ponging' the data back and forth between your control limits. It looks like it wants to run high, assuming there's no hardware failure. Don't you see variation like this all the time and just sorta 'ping-pong' it back into place? Thats what I imagine what your doing, or is it really that flat line all the time?
Wow, you've created quite the data tracking tool. Yeah, we have to live with the discrepancy between fingersticks and the CGM. Neither one is a real standard of any dependable measure. Has this tracking helped you? Any insights?
