i am looking at this discussion on continuous glucose monitors and don't see any posting for 2012. i am still new to cgm's but i also have experienced a lot of problems. the other night i had a bad insulin reaction at 3am, my wife woke me standing there with a glass of orange juice, my pillows were soaked with sweat, i still was aware of things and checked my dexcom which said my blood sugar was 115, after drinking the juice i went downstairs and checked with my accu chek compact plus and it said my blood sugar was 46 which meant it was probably up from earlier. i had taken no acetaminophen,so that was not a problem. obviously i am up set, this is not the first time that this has happened, but if your blood sugar is 46 when the cgm says 115 what is the point in having it. at least i was not driving a car when this happened. i believe i am doing everyting right. technical support advised that this was called drifting the last time i spoke to them about a similiar situation. i personally don't think that much of the product, it seems more accurate between 120 and 200 and it also will make you check it more for any signs of a rapid drop or increase in bg, but for it to be off by that much is a serious problem.
It is a serious problem, you're right.
I don't have a cgm yet. Still trying to decide on getting the Dex. So far, the issue that you describe is the main thing holding me back. I hear that the more you calibrate it with actual blood sugar readings, the closer it is to your actual reading. Have you been doing this?
This technology can be pretty useful, and I hear of a lot of people who love their Dexcom or comparable cgm. But you have to keep in mind, this technology is still in it's infancy and can only improve with time as people like you and me use it and report on it.
I know it can be scary to have those lows--thankfully your wife was there for you. Bottom line, do what is best for you! If you don't think your cgm is worth it, don't use it. Are you still in the 30-day window to be able to return it?
CGMs are not an actual measure of Blood Glucose, but body fluids. My readings are often behind what my actual BG is. When your BG is stable, it is the most accurate. I use my CGM to tell me when changes are happening. What is your alarm set for? Mine is set on 80. Could you have slept through the alarm?
You may have been going down fast, and the CGM couldn't catch up.
I use a Medtronic CGM. I am really happy with it.
It's not what the CGM says "the number" is, it's the "trend", which way it was going? If my BG is changing, the CGM usually runs about 20 minutes behind my actual level but, if it's plummeting, like if I was going to eat, bolused and got distracted or something, the difference can be quite a bit bigger? To me, the big use of the CGM is to get numbers set correctly but spotting "chunks" of time where you are regularly lower or higher than you want to, so you can then figure "is it bolus or basal, what do I change?"?
well that may be true, but if you are asleep and the reading has gone down for awhile and stops at 115 and you are at 45, the trend doesn't do you much good. i agree with your other recommedations
look, its best to be sure you have optimized location and performance before trashing ino ash can.
web sites like this one provide excellent feedback and guides to using.
in the case of this product that has low alarm limited at 100 is dead-butt idiotic. one does not have a user setable one to catch descending trend earlier so one can be alarmed - wake up earlier and deal with. lows are super critical and concern over accuracy rightly placed.
acidrock23 makes critical point as i want to know as early as possible as glucose starts heading down. 100 is too late, my sugar is decending to hades at light speed and takes agressive action to brake.
Where do you have sensor placed. if on gut move it to better locations - arms, thighs.
i find gut location useless and many points off from fingertip caveman readings.
so many folks have had a problem on this approved site and had to move it.
in my case gut was 160 and fingertips was 238. once on my arm, the biggest difference occurs in glucose sea change whereby cgms is slow catching up. when glucose moving slowly my readings are within 10 points of fingertip. on sea change may see 10 to 20 points off as cgms has time delaY ON FAST SEA CHANGE.
ANY MORE THAN THAT; make sure you are not rolling over on or jarring sensor and disrupting the sensor interface.
also, be sure to clean back of transmitter module prior to inserting in sensor platform.
also make sure sensor platform bandage is not letting go and not holding sensor firm to body. if so there are some excellent products that help sensor stay attached and prevent body scavaging the adhesive off the sensor platform. skin tac; skin prep and others.
What does, Sea change, mean?
sea change - one minute ocean flat/calm; next minute 6 to 15 foot waves.
In this case, I used it to describe the body blood stream glucose changing faster than cgms can track.
For me, usually gut/intestine glucose release is slow and climbs/falls slowly and cgms tracks just fine.
When liver dump/glucose add occurs, I have large liver and it can really shove the glucose out - outpacing the cgms. Hard as it may seem, one can track faster on caveman machine than cgns can and thats including time to do multipe fingerpricks in a row as well,
Hope that helps.
I like your rather personal analogy, jims.
This has happened to me before too and it's really scary. I still love my dexcom though for all the times it *has* saved me. One of the alarms that has helped me more than I can count is the alarms when you're dropping fast...I hate those straight down arrows! Luckily I don't get them often anymore.
The main benefit I've gotten from my Dex is the ability to see when I'm dropping and stop the fall before I get low. That's a tremendous value in my mind.
I look forward to the day the technology is perfected enough to be totally accurate.
I often get similar inaccuracy at night due to the interstitial fluid (that the sensor is reading for glucose) becoming stale. Blood flow slows down during sleep and it is interesting to see the accuracy temporarily improve if I get up to use the bathroom because moving around gets the blood flowing again. I don't get that kind of inaccuracy during the day.