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Ratios change, HELP!

Pepsi Max

Well-Known Member
Messages
162
I have to make some changes to my Bolus ratios on my Medtronic pump but I'm having problems converting from a DAFNE ratio to the pumps ratio... e.g. For every 10g of carbs I eat I take 1 unit of insulin. So this goes on the pump Bolus wizard as 10 i.e. 10/1=10. So if my ratio changes to 2.5 units for 10g of carbs this is input into the pump as 4 (10/2.5=4). My DSN told me over the phone to increase my units to 3 (for every 10g carbs) but when I divide 3 into 10 I get 3.3333... The pump will only allow me to use whole numbers...am I calculating wrong? Help!
 
Good morning

Just use 1u for 3g carb and don't worry. You seem to need a lot of bolus at the moment so are your basal rates set ok or are you new to pumping and finding your way?
 
Hi @Pepsi Max, I've just checked on the Medtronic 640G. You enter the number of grams per unit of insulin. As you are taking 3u per 10g grams, your ratio is 3.3g per U. Below 10g/U, you can enter in increments of 0.1U so you will need to enter 3.3 as your carb ratio.
 
Thanks but that won't work... Can only enter whole numbers...my DSN doesn't even know
 
hi pepsimax
for this evening until you can talk to your DSN maybe use 1 : 4 as it is a bit more conservative
 
Thanks all.... My DSN has decided to leave my ratios since my last hbA1c came back at 7.7% ....
 
Hi all, I posted this issue a month ago thought I was sorted but I'm back to square 1...please help I don't know how to set my ratios... Neither does my nurse. She just keeps making changes to them...I have to make some changes to my Bolus ratios on my Medtronic pump but I'm having problems converting from a DAFNE ratio to the pumps ratio... e.g. For every 10g of carbs I eat I take 1 unit of insulin. So this goes on the pump Bolus wizard as 10 i.e. 10/1=10. So if my ratio changes to 2.5 units for 10g of carbs this is input into the pump as 4 (10/2.5=4). My DSN told me over the phone to increase my units to 3 (for every 10g carbs) but when I divide 3 into 10 I get 3.3333... The pump will only allow me to use whole numbers...am I calculating wrong? Help!
 
Hi @Pepsi Max Tagging @Juicyj for you as I think she has a Medtronic.

Your Maths looks right. Why doesn't the above advice to set it at 4 to be cautious work then?

I've never done DAFNE so I've never heard ratios expressed in that way before. It would be easier if your nurse expressed them in the usual way - 1 unit of insulin to X amount of carbs. As you're saying you can't enter 3.3333 then entering 4 would give you slightly less insulin (to be on the safe side). That is, 1 unit to 4g.
 

Firstly that's one heck of a lot of insulin for 10 carbs are you sure your basal is correct?
Secondly if your DSN hasn't a clue then talk either to the Medtronic rep of ring the Medtronic help line. Surely also the pump manual has the information in it?
 
I used to have a bit of trouble using the Combo pump with my eve meal carb ratio.?......1u for 9g carb delivered a bit too much bolus, but 1u for 10g carb delivered too little. To get the in between and use 1u for 9.5g carb, I used 10u for 95g carb which then made the pump calculate the bolus a bit better.

It might be atm that yr dsn is trying to get yr bg lower using the bolus but as time goes on, you will most likely start to adjust the basal to sort out Novorapids action.

It does get easier though so bear with it all until you feel confident making the changes you need to get the harmony you want.
 
I have a 640g and like @tim2000s i can input at least 1 decimal place. Are you the same carb ratio throughout the day? I find I need more in the morning when i'm most resistant and least around 4-5pm.
 
The way ratios are set on your pump (Medtronic 640G) is different to the DAFNE way.
Dafne go by Units of insulin for 1cp (Carb Portion). 1 carb portion is actually 10 grams of carbs. All your effectively doing is putting a decimal point between the 1 and the 0 ie 1.0

On the pump it wants your Grams of Carbs for every 1unit of insulin.

Your 3.3333 figure will go on and on and on, on the calculator.
All you need to put in is 3.3
So this means that the bolus wizard will calculate 1 unit of insulin for every 3.3 grams of carbs entered in the wizard. For example a 60 gram carb meal like 4 rounds of medium sliced bread will give you an insulin dose of 18.1 units of insulin.

If you work this out on a calculator Divide your grams of carbs to be eaten (60 carbs)by the carb ratio (in this case 3.3) which will then give you the amount of insulin (18.18 the bolus wizzard might express it as 18.1 units).

I hope this helps and i hope i haven't insulted you in the way of which I've explained it.

Regards

Martin
 
Not really, well not compared to when i was on MDI. My ratios where 3 units of insulin to 10 grams of carbs for beakfast and lunch. My night shift meal at 0100 hrs was 3.5 units for 10 grams. Now get this one, my evening meal was 5 units of insulin for 10 grams of carbs and it wasn't enough.

Going on the pump has changed this drastically, I'm using a lot less bolus and a lot less basal and got rid of all my highs and said good bye to DP.

Regards

Martin
 
@Pepsi Max, if you need more insulin than 1u per 10g carbs, you can get decimal units. For breakfast and lunch, my ratio is 1:10 but for dinner it is 1:9.5, which means you are able to enter a ratio of either 1u:3.3g or 1u:3.4g. However, if this is a huge increase in your usual insulin dose, remember to test, test, test!

Also, if your DSN doesn't understand the Medtronic system, ask for someone who does. If your hospital issues Medtronic pumps, they should have (or be able to put you in touch with) a member of staff who is qualified to advise patients on its correct use.
 
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No that's it!! I'm used to DAFNE so it was 10g carbs etc now I understand that the pump is looking for carb grand per 1 unit...and now I understand what my DSN is saying! I hope
 
Pepsi Max said:
Thank you all! I am pre pregnancy clinic so constant changes to Bolus & basal!
Click to expand...

If you don't already have them, you'll find the books Think Like A Pancreas and Pumping Insulin really helpful.
You should be confident adjusting your own basal and ratios, checking with the DSN if you're concerned. They'll be a huge amount of adjusting in pregnancy so it's best to get into the habit early.
 
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