Measuring IOB

Here is an older document on IOB. (2010)

diatribe iob article

Mentions this about omnipod being different in its iob determination.

Both OmniPod’s PDM and the Pocket Compass Software that works with AccuChek Spirit take a very different approach to IOB calculations. Both of these systems only consider boluses that were given to correct high blood sugars when figuring IOB. For example, if you gave 6 units for a meal and 2 to cover an above-target reading, the 6 units are essentially ignored in all IOB calculations. Only the 2-unit correction portion is taken into account. This leads to much lower IOB calculations than we see in other pumps, and hence less bolus reduction and more aggressive insulin dosing.

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From the 2014, 2015 Podder’s Handbook for the Omnipod UST400 User’s Guide:

" Insulin on Board (IOB) the amount of
insulin still working in your body from previous meal and correction boluses."

“Meal IOB, which is insulin on board from a previous meal
bolus, is subtracted first from the current correction bolus, if
any, until it is zero. However, any remaining meal IOB is never
subtracted from the current meal bolus.”

“• Correction IOB, which is insulin on board (active insulin) from
a previous correction bolus, is then subtracted from the current correction bolus, if any remains, until it is zero. At that
point, any remaining correction IOB is subtracted from the
current meal bolus.”

I believe the Omnipod home screen will “accurately” show your total IOB from both correction and meal boluses, but that it will only subtract Correction IOB from new boluses if you are using the Suggested Bolus Calculator. It does confirm that Meal IOB is not subtracted when using the Suggested Bolus Calculator. I may have known that at one time but have forgotten. I stopped using the SBC about a year ago…about when I joined FUD…hmmmmm…

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Intergrated Diabetes has a chart that at best is a rough guide for figuring out IOB. I would use this excel sheet as a guide only and not gospel. Link is here

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Sorry for the delayed reply - rest assured that I’ve been reading your responses and thinking them through, but my attention turned to what apparently was yet another growth spurt this week. So. Much. Eating. And high numbers to go along with it.

I think you’re right. We are still working on prebolus timing, especially in the morning when predawn hormones are fighting back, prebolus is taking forever, and we are trying to get out the door for school and work sort of on time. At some point (7:45am to be exact), she just has to eat even if the insulin isn’t ready yet or else we are all late.

I’m pretty confident in our basals. Even this week, when I could get her to stop eating for a little while, the CGM line would flatten out, just at a high number.

This is perfect for wrapping my head around IOB. Thanks for sharing.

This is a good idea. We still see spikes after she eats straight protein/fat with nothing else mixed in, but they aren’t as dramatic as carbs.

I appreciate that this would be a tricky test to create for at home use. But I guarantee you I will not forget about advocating for ways to measure it either :wink:

Thanks, all.

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This may not be possible for your daughter, but this is why I’ve gone to a portable breakfast. I take my breakfast bolus once I get in the super long car rider line at my son’s school…and then I eat my breakfast once I’m almost to work. That’s about a 40 minute spread for me. It’s “fixed” most of my problems for me bc now I’m in range for lunch.

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Also, once you have a crap breakfast response, you usually roll into lunch with a crap number which usually leads to rage bolusing, and an epic low right in the middle of the afternoon. Not a good result. The days we are able to control breakfast, are usually the days when we have control the whole day.

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I know i am no longer a child with D, but, IMHO, i have for the longest time required insulin for any protein as well as any fat. so, just my 2 cents, but a definite consideration when “fasting and IOB” is required for a basal test. if you know that your child does not require insulin for these types of food, i think its a fabulous idea. very sneaky and very clever.

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