Question about pumps generally, and omnipod in particular.
When delivering a bolus, does the pump suspend basal delivery, or does it add that to the bolus? This is really most relevant to extended boluses -- if I have an extended running for 2 hours, what happens during that time to the basal?
Logic says it would be added in; after all, the bolus is already "dedicated" to a count of carbs being digested, while the basal is calculated as a continuous, all-the-time background. Not adding it to the delivery would seem to lead to highs.
All that said, is the behavior of pumps universal on this, or is it one of those things that varies by pump manufacturer? And then finally, if the latter, anyone know what the case is for the Omnipod?
The reason for knowing this is I want to calculate how much insulin has been used from a new pod at the end of the day when I've done a pod change. As a type 2 with relatively bad insulin resistance (1:3), I'm on the two-day change regimen, and I'd like to be able to manage my diet and insulin usage when necessary to avoid having to change a pod in the middle of the day when I'm not home. I've found I like thigh placement the best, which makes pod changes a little involved away from home.
Well, my pod manual is in the other room, so I'm going off the cuff here. But I'm about 90-something % sure that basal rates continue uninterrupted unless you suspend them. Now let me go see if I can find the manual where it confirms that :)
got it! Regarding boluses, Page 29 of the manual states "This extra dose is in addition to the basal rate delivered through-out the day and night (see Chapter 3, Understanding and Adjusting Basal Rates)". So yes, the basal continues as programmed unless you override it with a suspension or a temp basal.
I use a Ping, but I'm pretty sure that basal and bolus are completely separate. So an extended bolus should have no effect on basal, just like a temporary basal should have no effect on an extended bolus. (Also, IOB only counts boluses, and for some pumps it only counts a certain type of bolus.)
Thanks, Kate! (and thanks for finding it in the manual -- I looked this morning and couldn't find anything in the index).
It makes sense. As I said above, the bolus is already completely "used up" by the carbs or correction your bolusing for, so it would tend to creep your BG higher during the day if basal wasn't added to it.
I'm not so sure about that. Pumps can deliver very small doses (most as little as 0.05U, some down to 0.01U!). So I'll bet basals are delivered at the smallest "chunk" possible, with the highest frequency possible. This would more closely match pancreatic oscillation of basal insulin.
Be clear, though, I'm purely speculating here... I don't have any authoritative info about it. Think I'll email my Omnipod rep...
hello! in terms of knowing how much insulin has been used, there are a couple ways to figure this out... more general or more specific.
note: i am not on the new pod yet, but hopefully these instructions still apply!
general when you go to change your pod, you should see the amount of insulin left at the top of your screen. so, i'm changing mine every other day and usually when it's the day to change it, i'll see it's down to about 15 units.
specific: go to home > my records > insulin delivery
it will tell you how many units have been delivered each of bolus and basal by day.
of course, you always want to load your pump with a bit more than you actually think you will use unless you eat exactly the same amount of carbs every day. if you are new, you will be able to pinpoint it more and more accurately as you go along, but when my prescription for insulin is written, i make sure they write it for more than my actual use to account for the small bit of insulin that might get thrown away when i change.
There was a discussion here on tudiabetes about basal delivery of omnipod: the timing starts at activation time, and for very low basal rates as in young children it is important when you do a pod change as you could miss or double a "basal impulse". I found this subjected talked here http://forums.childrenwithdiabetes.com/showthread.php?t=56807
