Guardian CGM and pump

I just got a guardian CGM how many use a pump with this CGM versus using it with MDIs?

Hi Crystal, I use a guardian 3 CGM with a medtronic 670g pump.

I have used the pump and CGMfor about a year .I talked to the nurse instructer and she said that when the first sensor says to replace it ,Ileave the sensor in the body remove the transmitter, charge it and when fully charged reconnect it and punch in connect new sensor .These sensors are exspensive and I can reuse each sensor 3 times before replacing it.
My question is why when I calibrate sometimes it will say Calibration not accepted re calibrate again

I have the Guardian CGM and the 670G pump. The trick Vic mentioned does work and you can get more life out of the sensor. Also in talking to Medtronic, if the sensors are not lasting 7 days, give them a call and they will send you new ones for free. Just keep the old ones to send back in if they ask for them and they mentioned you can keep the old ones until you get a collection of them before you send them in. You do not need to send them in one at a time.

It seems that the pump gets confused in my case on the 4th or 5th day and start asking for BG readings, then to replace the sensor before its life is up. Taking the transmitter off and charging it, then telling the pump you have a new sensor seems to correct the problem.


Thanks for the feedback, it’s much appreciate!


Crystal Laplante

I am trying the guardian sensor now and still use MDI.
I am still not interested in having a pump yet.
I dont like being “plugged in” though I love knowing my trends

there are a few reasons why it wouldnt accept your calibration.
If you are under a certain number (I think below 70 it gets tricky, and above a certain number too - I dont have the manual with me right now) and also if its moving a lot, either going up or down.

so the best time to calibrate is when you wake up , before meals, or before exercising so the trend is as flat as possible. also, make sure your hands are clean (some residue on your hands may trick your Glucometer in thinking you have higher or lower BS than in reality) and make sure you check your sugar and calibrate right away.
hope it helps

Hey! I use the guardian sensor with the Medtronic 670g pump I feel that they work great together and personally make me feel a lot safer than using a pump and sensor that do not “communicate”.

Thanks for the insight:)

I just started using the Guardian sensor with my iPhone. In February I was planning to update it when I can switch to a new Medtronic pump that has the algorhythms etc. So far I am not confident. My first sensor gave me wrong readings and kept losing the readings until it told me to change the cgm. I put a new one on and it didn’t even last a day. One reading was low when in reality I was actually high.
I think my problem is lack of body fat which is what my sensor is meant to go into- my stomach and backs of arms are more muscle than fat. I’m 5 11 and about 125lb (and desperately unsuccessfully trying to put on weight). Has anyone else had the same problem. I feel like I am going to end up doing MDI. I was really looking forward to the new pump. Does anyone whose lean have a pump and CGM that work for them?


I dont think body fat is the trick.
I actually found out that if I put them on my stomach or the back of my arm like its supposed to, I do NOT get good readings and they do not last.
I think its because these locations move too much.

If you get the message that it needs to fix itself, and can take up to 2/3 hours, thats most likely because your sensor is moving. I didnt think it was when they told me that, yet, when I removed my sensor, I realized I was completely sore and my skin was raw. It was moving I just didnt realize it was.

I also calibrate 3 times a day.
in the morning before I eat, so I am stable and low.
before lunch or dinner, again, where I am stable and low
and finally before bed time, where I should be stable and low.
notice a trend? if numbers fluctuate a lot, the sensor tend to miscalibrate.

remember also that your glucometer may be 20% off, your sensor may also be 20% off and that (like their videos explain) the blood glucose is the locomotive, and the sensor reading is the train wagons. if you are going up, the sensor will be lagging behind and therefore be lower. if you are going down, your sensor number will be higher than your glucometer’s.

surprinsingly, my best readings are on the upper part of my chest, and on the top of my lower arm. I love love my lower arm. it pulls on the hair a bit on the first day, but after that, its completely out of my mind. doesnt move, doesnt bother me when sleeping and is so close to glucometer most of the time.

There is also another reason you may not be getting good results. If you are reading online (facebook and other groups) you may have noticed that some people can extend their sensors for a very long time, and others can barely get a few days. for some, it has a lot to do with their body’s chemistry.
That sensor, inside your body is a foreign body, and your body tries to get rid of it. part of that chemistry makes some people having very poor readings. yet someone who takes immunosuppressive medications (what prevents the body from rejecting a transplant- a foreign body) can have a sensor last for more than a month, crazy right!

hope it helps!

Do you use a pump with the guardian? I have the 530 pump and have not used it with the guardian CGM yet. The pump without the CGM was yielding erratic sugar. I want to understand the best way to control my sugar. I can’t get Medtronic’s latest pump for another couple years when insurance with authorize it…