I’ve been using the Medtronic Real Time System for about nine months and have had alot of problems with calibrations. The directions say the numbers should be w/in 20% of each other, but I regularly got numbers with 40%-60%discrepencies. Anyone else having problems with this unit? I have the older, bigger transmitter. The people at Medtronic have no solutions for the problem. My A1c’s have been well below 6.0 and I follow the directions to a “t.” Any suggestions or comments?
Mike,
I too have been on the Medtronic RT System since Feb.07. I have found that the times I check (due to required calibration alarms) my blood sugar when the levels are changing rapidly, I will not be very consistent between the two (glucometer and Pump/senser). It’s best for me to try to calibrate when the pump is not showing one or two up or down arrows in the display. However, that’s not always possible.
I have been using the newer transmitter since July . If my number is not stable I do not calibrate until im sure it is . I just lose that time . So if Im do for a calibration at 6 pm I might go ahead and do it at 4 pm if I know my number is steady because anythin can happen by 6 pm . I do find that if i have a extream low or high it is usually just off then untill I recailbrate with steady blood sugar . But for the most part Im getting good results .
Do you calibrate first thing when you wake up ? Also I find it best not to do it before meals …maybe a hr before .
Hello: I do my calibrations at times when my bg is not changing rapidly (no arrows showing). I’d been doing the calibrations before meals and before bed, checking with the Minimed folks as for timing. They say I’m foolowing their instructions. After constant phone calls, they agreed to replace my transmitter (which I don’t believe is the problem) with one of the new generation one’s. I’ll see how that works.
Thanks for your comment, Mike
Hello: I do my calibrations at times when my bg is not changing rapidly (no arrows showing). I’d been doing the calibrations before meals and before bed, checking with the Minimed folks as for timing. They say I’m foolowing their instructions. After constant phone calls, they agreed to replace my transmitter (which I don’t believe is the problem) with one of the new generation one’s. I’ll see how that works.
Thanks for your comment, Mike
Mike , you are not calibrating at every meal are you ? . My trainer told me no more than 3 times a day try to only do to the more you do the more it will be off .
Tracy: I see that different Minimed trainers tell people different things. My “trainer” told me to calibrate four times a day before each meal and before bed. In fact, Minimed reccomends this regime even though the instructions tell you it has to be done minimally once every 12 hours. I just confirmed that by calling the help line. I have found that one can get different answers from different people at Minimed. The person that trained me is a type 1 diabetic and has been using the cgm for several years now. Hope this doesn’t confuse things more for you.
Regards, Mike
i have read some dicussions/blog sites that suggest that for some people the Dexcom sensors work better than the MM sensors…and the MM sensors work better than the Dexcom for other people. Some people both work equallyl, other people neither work.
Probably not what you want to hear.
One nice thing about the Dexcom is they encourage you to calibrate as often as you like. and have suggestions for what to do if your sensor is off by more than 20% from meter reads—thier suggestion is to calibrate when running level—then 15 minutes later, calibrate again…so 2 calibrations 15 minutes apart - within 30 minutes Dex should get back in sync. With Dex I have had much luck with this. BUT I dont think MM would encourage this behavior.
it doesnt confuse me , I know all about getting mixed messages from minimed …lol … My trainer was a type 1 on the meter also . . It would be nice if you could try a dex and see if it worked any better for you . I really love my CGMS most days it is accurate for me all day and that helps to not over eat to keep from going low . I guess my next Hba1c will tell .
Thanks Mollie, I’ll check into the Dexcom unit.
As you can probably see, I’ll look into the Dexcom cgm, and give the replacement transmitter, with new sensors, a try and see what happens. See ya’, Mike
Hi again Mike.
It has been a somewhat frustrating time getting used to my Minimed CGMS. I’ve been back & forth with my CDE pump trainer and the 1-800-MINIMED support techs a lot about different issues. One support tech told me that the CGMS wasn’t for everyone. I didn’t like hearing that. I wanted this to work.
For all my frustration with the CGMS, results have been very, very good so far. Two A1Cs since April, each being my record low value at the time. First was above 6 and second was 5.5. The 5.5 surprised me and I think my diabetes doc too. I have to reduce that “standard deviation” value (reducing the wide range of the sensor’s results. There has been no increase in problems with lows When the CGMS has been working (95% of the time), I have been able to deal with any impending lows.
Pump trainer told me 2 calibrations a day. From listening to Minimed people, it sounds like they are still learning about about correct usage from both study & from users. One of the biggest helps for me has been using the IV3000 dressings to hold the sensors down to my skin.
The A1C values og "well below 6): did you manage that before the CGMS. I never did. If you did, you probably work really hard at management. Good luck.
Hey Steve-Yea, my A1C’s have been below 6 since using the pump for just over a year. I haven’t seen any change since using (or not using, as the case may be) the cgm. The original trainer I had for the cgm is diabetic and has been using it for some time, having taken part in the trials. She’s had some good tips such as letting the sensors acclimate in your skin for more than an hour before attaching to the transmitter. I don’t think she’s working for Medtronic any longer so its tough to get a hold of her for more inside information, but I’ll talk to her about the 2 calibrations/day deal.
Have you had “suggestions” from the trainer to use the sensors for more than the three days that Medtronic says they’re good for? I’ve been using them for up to eight days w/o any problems. Of course, other than the calibration discrepency problem, which does not appear to be caused by use beyond three days.
Thanks for getting back in touch,
Mike
Just started last week and still using my same sensor after calibration errors and bad sensor alarms. I got the bad sensor alarm again yesterday, but got it to work again for me last night and ever since the sensor has been matching my meter 
It also caught a low for me this afternoon. It started beeping, I went to show my boss (she is a nurse, plus man can she talk), she started talking and talking and talking and finally I said IT CAUGHT A LOW, 15 minutes later, and she said OMG, how low, I said 74, gotta go get a snack.
Bad thing now is this is day 6 on this sensor, so I know I will have to yank it out and start all over again. 
I have found the sensor does not work well if I calibrate when my bgs are not steady. I was told by the trainer last week to calibrate before every meal and at bedtime. I now only do every 12 hours and that is working better,
Hoping the sensor works one more day where it matches my meter perfectly. I am a bit disappointed as I thought I would be testing a bit less, but I think I am testing more. I think things could be improved, but for now this is what I fought for and endo yesterday said I have to give it 6 months to work out how it will help me.
I am thinking that perhaps once I take it off to change out, I may miss the little bit of security it has given me of catching lows.
Karen