Normally my G5 is wonderfully accurate to the point that you would have an extremely hard time convincing me to get rid of it. However, over the past 2 days, have been getting increasingly inaccurate readings from a new sensor I inserted Late Thursday night. When I inserted it, I realized that I had done it backward from what I normally do. Normally I place the angle of the needle so it goes toward the middle of my tummy, as to get access to the most “meat”. This time i had done it towards my side. I think I did this because I’m right handed and was placing the sensor on my left side. Wasn’t an active decision, just ended up that way.
Well, over the next 2 days at calibration time, the BG meter readings were getting further and further away from what the G5 was telling me. Came to a head this morning when my receiver was telling me that I was 75 but 3 BG tests put me at 95 98 and 103. I replaced the sensor and am waiting for it to warm up as I type. I don’t know if I got a bad sensor or the angle of the sensor, being more shallow due to my mistake, cause bad readings. Either way, I’m still a G5 believer, just a frustrating 2 days of huh growing to wtf, and finally, eff this.
What are your thoughts on what could have happened. Bad sensor, bad placement or both? Or something else. I ain’t proud.
Sure, I did that with a Omnipod a couple weeks ago - spun it 90 degrees, just to change up the catheter placement. But, the catheter came free because my technique was off. Totally wasn’t receiving any insulin until I noticed a couple hours later. Only time that has ever happened.
I wouldn’t consider your sensor reading of 75 versus an average of three fingersticks of 98 an entirely unreasonable performance. It’s not something you want the system to continue with and that’s why it needs calibration. But you did say the difference between your fingersticks and the Dex reading was growing over a two-day period.
You made the choice to pull the plug and start over and that’s OK. I might have stayed with it a bit longer but that’s me. Your sensor may have been complaining about placement but I don’t think reversing direction should be that big of a deal. If a little bit of dried blood is present when you withdraw the sensor, I haven’t found that to mean much. If the sensor bandage is soaked with blood and blood comes out after withdrawal, then that’s another thing. In that case, it might mean the sensor itself could have been blood-fouled.
In any case, you’re learning. Just chalk it up to experience. The Dexcom sensor system in general is good quality for most people. You’re on to a new sensor and paying attention. That’s what counts. Good luck!
It depends on what you are used to. We typically get calibrations that are within single digits. A calibration difference of 10 or greater (when picking time of calibration when BG graph shows in-range and straight and level) is unusual enough to make us question what is going on.
I understand some people do not get as good accuracy. But when you are used to readings and calibrations as accurate as we get then when a calibration comes up as greater than 25 points off and this repeats for the next calibration then we know something is wrong. The question is of course “what” is wrong.
I agree that the context is important. I think we each develop our own sense of what is acceptable and what is not over our time living with the Dexcom sensor systems. There’s not an absolute metric to judge against. Whether to pull a sensor or not is a judgment call. I found lately, especially since using a system that makes dosing decisions based on the Dexcom number, that I’ll err on the side of pulling too quickly. Your experience will vary. I think the original poster did the right thing in pulling the sensor.
Yeah, The reason i pulled the sensor is that normally, for me anyway, the dexcom vs fingersticks is around 10% difference, sometimes spot on. For the first 2 days or so of a new sensor I fingerstick maybe 6- 8 times a day, just to compare, not calibrating with those unless its time. I rely on the dexcom to bolus, so I like to make sure its within reasonable tolerance. I hate the feeling of lows. The confusion, shakes and sweat are disturbing. This one was just way out of wack for too long, even after a sensor restart. I have been building PCs since I was a kid, so I understand getting the occasional inexplicable bad part, just frustrating when my freaken life depends on it.
