Hi everybody, hope you're enjoying the summer at long last. I'm using a medtronic 754 insulin pump. The other day I bolused for a meal - about 4 units I think - and I had no active insulin (showing on the pump) at the time. I've got my active insulin time set to 4 hours (novorapid) and three hours later it was definitely under 1 unit less, ie. less than 1 fourth of what I originally injected. Does this pump simply divide the active insulin time by the number of units or does it do something more complicated like have a peak (as in the real world) and then a valley? Perhaps I misread the pump at the time but I'd be grateful for the input from this forum.
Medtronic pump active insulin time?
- Thread starter skipbifferty
- Start Date
Just to add, when I was looking at the insulin time I did take into account the time it takes for the bolus to finish being delivered - and it didn't make sense either with the time I bolused or the time it finished.
Ok, today at 1.30pm I bolussed 6.5 units with no active insulin at the time. Checked at 2 hours and it was slightly under 3.2 which I thought was about right. Then at the 3 hour mark it was definitely showing under 1.2 units. 1.2 X 4 = 4.8 units so that's about 1.7 units unaccounted for! Does anyone know what's going on here?
mrman
Well-Known Member
- Messages
- 2,419
- Type of diabetes
- Type 1
- Treatment type
- Pump
Not sure with that pump, but my accu chek only shows the correction doses of active insulin. so if I bolused 6 units for a meal, those 6 units would be allocated for against the meal as needed but active insulin would show as 0. However if I needed 6 units plus a 1.0 correction, then active insulin would show only as the 1 unit correction slightly decreasing over the active time of the insulin.
Sent from my GT-S5360 using DCUK Forum mobile app
Sent from my GT-S5360 using DCUK Forum mobile app
Thanks for the reply Brett. I've just found out the answer. Medtronic and Animas are supposed to use a 'curvilinear' graph whereas the Omnipod and Cozmo use a 'linear' graph. In the words of another pump user (on the net), 'The formula generated is an approximation since the pump companies keep their formula a tightly held secret!' (http://forums.childrenwithdiabetes.com/ ... hp?t=44485).
This article explains it in detail: http://www.diabetesnet.com/diabetes-tec ... n-duration.
For your pump, Brett, it probably doesn't matter too much but I think, for people with Medtronic and Animas pumps, it's important to be aware of this. I probably relied on the number too much anyway because I was always aware that the active insulin time is different for people anyway. I wrongly assumed though that it was a linear calculation.
This article explains it in detail: http://www.diabetesnet.com/diabetes-tec ... n-duration.
For your pump, Brett, it probably doesn't matter too much but I think, for people with Medtronic and Animas pumps, it's important to be aware of this. I probably relied on the number too much anyway because I was always aware that the active insulin time is different for people anyway. I wrongly assumed though that it was a linear calculation.
