670G & Guardian 3 Double Bolus Glitch


Middle of the night, Auto Mode Readiness screen comes up and requires a BG. Test BG and it is 209. Pump recommends a 1.375 bolus, so I do it, calibrate and go back to sleep. 5 minutes later pump beeps with a message that a 209 BG requires a bolus. Confused, I go through the prompts and it recommends a bolus of 1.275. I continue with the prompts expecting that the insulin on-board from the previous bolus will cancel it out, but it doesn’t. I get all the way to the final screen to “deliver bolus”, which of course I do not do. This is bad. And scary since this is with my 11 year old daughter who relies on the pump to know what to do when we are not around. I can easily see her going ahead and delivering the second bolus, essentially doubling the amount of insulin needed for her BG. There is no record of the second “alam” in the history of the pump. Medtronic Tech doesn’t seem to know what happened either. We are somewhat new to the 670G, about 3 months, and are still trying to figure out the Auto Mode BG requirements, which can be confusing. The best guess I have is that the Pump, somehow, did not recognize the first Bolus, maybe because it was delivered during the Auto Mode Readiness BG requirement and so it beeped 5 minutes later to remind me that a Bolus is recommended with a 209BG. Wondering if anyone else has had a similar incident or more experience with the system to explain what happened. Thanks.


One thing that happened to me repeatedly with the 670, both in auto and manual, is that I would go through the bolus process and think I’d finished, only to get timed out because I’d never hit the final “Confirm” it always asks for. One reason this tended to happen is that it makes the exact same beep when you reach that screen that it does when you actually push the button to confirm, so if you’re not paying close attention (it’s the middle of the night, say) you think you’ve started the bolus when you haven’t.

Not sure if this would be the explanation, but the fact that the pump didn’t record your initial bolus would seem to indicate that somehow it was never delivered. For all the annoyances I had with it I never saw any issues about the system reliably keeping track of IOB. But I frequently ran into this “Just one more confirmation!” nonsense that about drove me nuts.


@DrBB has a point. Did you check the insulin on board to see if the bolus had indeed been delivered?


Agree w/DrBB on this too. I have done exactly the same thing several times. That is an aggravation with the 670… too many button presses to get to the what you need.


Thank you DrBB. IOB was definitely recorded, as this is exactly why I was so confused. I have had some other bizarre incidents where the pump’s two modes don’t seem to know what the other is doing. Like testing a BG, delivering a Bolus and then calibrating, only to have auto mode immediatly require that I enter a BG and calibrate to stay in auto mode. It’s like auto mode has no idea what is happening or happened while not in auto mode.

I will say that the part I am most unsure of with the incident in the middle of the night, is that although I am 100% certain that the first bolus of 1.375 was delivered and on-board, I am less certain about the second recommendation of 1.275. I may have miss read the amount and it could have only been recommending 0.275. Since I did not deliver it, it was not recorded in the history, so I will never know for sure. But, if the pump was in manual mode when I entered the BG and delivered the first bolus, and then when it went back into Auto Mode it may have requested the small bump, which I understand is something it might do.

I appreciate the responses. If no one else has had a similar incident, it most likely was due to my sleepiness when reading the screens in the middle of the night.