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Bolus on board calculator?

PaulinaB

PaulinaB

Well-Known Member
Messages
594
Location
London, UK
Type of diabetes
Type 1
Treatment type
Insulin
Hi all!

I'm curious, has anyone heard of a good app that can calculate the bolus on board (or insulin on board, whichever name you prefer)? Basically, similar thing as insulin pumps have - you tell it how long your bolus works and when you injected and it shows you how much units you still have working.
I can do it manually approximately, but since the action is actually a curve not a stable line, then a more advanced calculations are needed.
 
I believe an Android version is coming soon, but in the meantime it also works on iPods version 4 and upwards.
I bought a cheap iPod on eBay just so I could have this and Carbs and Cals downloaded on to it. I works beautifully :D

Signy
 
surely you could write your own spreadsheet?

What's the curve you're trying to approximate? I bet I could do it in half an hour.
 
ElyDave said:
surely you could write your own spreadsheet?

What's the curve you're trying to approximate? I bet I could do it in half an hour.
Click to expand...

I probably could :) I need a novorapid curve, since that's what I'm on. My action time seems to be 4h (bleurgh..., sooo long). I keep over-correcting because it's so long and I end up low :|
 
I use Novorapid in my pump and found that its onset is slightly delayed causing a slightly higher bg about 2hrs
after injecting but then it has a tiny kick in its tail on the final 45mins of its action causing the low bg feeling. After spending some hours basal testing, I now just eat a jellybaby. Another thing is that ive also gone the lower carb way of eating as that helps smooths out the Novo action on my bg.

What is yr target bg before eating and how high do you let yr bg go before you correct and how many hrs do you wait before doing the correction?
 
My target zone is "single digits" :) On my CGM I have it set between 4.2 and 9.0 mmol/l.

I'm going to eat my lunch now, so I'll be able to show you better what I mean.

I'm at 5.6 mmol/l BG now (5.5 at CGM). I'll be eating a soup with 23g of carbs, using my 1u:5g ratio, that gives me 5u of Novorapid (it's actually 4.6u, but I can't do that with the pen anyway).

I try not to correct when I'm high after a meal if I'm sure that I did my carbs right - because it will come down eventually... If I'm frustrated, I will correct (which will have no effect for at least an hour anyway) and then come crashing down afterwards ;(
So if I had a IOB calculator that tells me "don't worry, you still have X units working", then I will know if I should wait or correct.
 
An hour later, my CGM is already freaking out. I had RISING (arrow up) alert and now I'm 9.5mmol/l.

The whole thing that make me look for IOB calculator was the thing I did yesterday - I ate my lunch and then 2 snack after that, all separated by some time (bolused for each). This caused my BG to rise up to 12-13mmol/l and stay there. i wasn't sure if I should wait or correct (and risk crashing down). I waited it out and it (finally!) went down.

I imported my CGM numbers into my graphs so I can show you what I mean.

At the bottom of the graph you can see the insulin doses (N6 -> novo 6u, etc...).
So I started eating at 13:30 (more or less) and at 4pm my BG was still going up... At this point I wasn't sure if I should start rage bolusing or what... as you can see it came down after all, but the whole thing took almost 6 hours to stabilize :\

Screenshot from 2014-08-12 13:22:25.png
 
A) try and get on a pump. Absorption from a pump is better.
B) Change insulin. Try any different one. Worst that can happen is you have to go back!
 
Do you inject Levemir twice a day or just once?
I always found that Levemir's action was a tiny bit delayed so I counteract with more bolus in the morning in order to prevent a high bg mid morning. Most peeps need more insulin to cover the morning and then less at lunch and as the basal wears off a bit, more insulin is needed to cover eve meal until they inject the basal again. Its all about balancing up the effects of the basal with the effect of the bolus on the food we all eat.
 
iHs said:
Do you inject Levemir twice a day or just once?
I always found that Levemir's action was a tiny bit delayed so I counteract with more bolus in the morning in order to prevent a high bg mid morning. Most peeps need more insulin to cover the morning and then less at lunch and as the basal wears off a bit, more insulin is needed to cover eve meal until they inject the basal again. Its all about balancing up the effects of the basal with the effect of the bolus on the food we all eat.
Click to expand...

Hey,

I inject levemir once in the evening and I find its action to be quite perfect for me. If I'm not eating or exercising, my BG stays stable through the day.
Levemir seems to have a small peak for me between 7 and 9am, so it's actually causing my morning bolus ratio to be smaller.
 
HThis is what I would do.....

inject some levemir in the morning ss its action will tske effect late mid morning. I would also reduce the morning bolus a tiny bit so thst the evening levemir didnt clash too much with the morning levemir. Bit
trial and error and bg testing to determine afternoon bg levels but with any luck they should be better balanced but as Eng88 has said you change to a different bolus that has a faster onset and slightly shorter duration to see if that helps or try the joys of pumping and alter all the hourly basal rates to try to achieve stability.
 
iHs said:
HThis is what I would do.....

inject some levemir in the morning ss its action will tske effect late mid morning. I would also reduce the morning bolus a tiny bit so thst the evening levemir didnt clash too much with the morning levemir. Bit
trial and error and bg testing to determine afternoon bg levels but with any luck they should be better balanced but as Eng88 has said you change to a different bolus that has a faster onset and slightly shorter duration to see if that helps or try the joys of pumping and alter all the hourly basal rates to try to achieve stability.
Click to expand...

Thanks for that! The graph I showed was caused by 1 meal followed by 2 snacks - each separated by some period of time. So it's caused by slow bolus, not not enough basal (I think). I don't want to mess with levemir anymore, I did a lot of testing and experimenting and it seems what I have is quite stable and I think it's as good as you can get with levemir - I have stable BG all day and any bigger injection causes recurring hypos.

My original question about bolus on board calculator was so that when I eat a meal and then within hour eat a snack (and bolus) and then within another hour eat another snack (and bolus) then after 3 hours from the original meal (where I would expect to be coming back down) I'm still high (2 snacks are working!) so a BOB calculator would show me - "don't worry, your last 2 boluses are still working!" and I'd know if I need to wait or correct :)
 
Not sure how useful that is combined with a cgm, but the accu chek Aviva expert has a dose advisor which includes bolus-on-board.
 
AlexMBrennan said:
Not sure how useful that is combined with a cgm, but the accu chek Aviva expert has a dose advisor which includes bolus-on-board.
Click to expand...

Ha! That would be useful... but you have to get it from the DSN don't you? I didn't see an option on their website to order one :(
 
Well, I got mine from the consultant at the hospital, at her suggestion (I'm fairly ambivalent towards "wizards" - if you can't do it without the help of wizard, IMHO you shouldn't be using one... which means that I don't really need the wizard...); I don't know if you can get them from other sources.
 
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