Confusing advice from diabetes professionals

[Arthur Leat]

While talking to a nurse at my local GP surgery recently, about a subject unrelated to diabetes, the matter of my type 2 diabetes came up. I mentioned that I was using the basal-bolus method of insulin management and was taking a 10 unit dose of slow-acting insulin (Humulin) at bedtime. She said this dose was far too low, and that the correct dose should be calculated by taking my weight in kg and multiplying this by a figure between 0.5 and 0.7. in my case this would work out at 34.

Following this meeting, I arranged to see a diabetes nurse, as I had not seen one for some time.

My method of dosing recently has been, if I was about to have a meal, to look at my bg before eating, see how much this was above the 5-7 range, allow 1 unit of fast-acting insulin (Humalog)
for each digit between 5-7 and the actual bg, then add 10 units for the meal, like this:

Actual bg: 15
Target (say): 5
Difference: 10
Add for meal: 10
total insulin dose 10+10 = 20 units

The nurse said this was quite wrong. I should be allowing 1 unit of insulin for every 2 (not 1) difference between actual bg and target. She went on to say that my target should be 8-10 (not the 5-7 that I had long believed to be the desired range), and,concerning the slow-acting insulin that I should start with 20 units (not the 34 as calculated above) taken with my evening meal.

I have followed her recommendations for three or four days, and my high bg levels seem worse than before

Where do I go from here?

 

[bilbie]

You really want to ring the nurse and tell her what is happening. Get professional advice, if you aren't happy see another.
do you mean humulin N? That is an intermediate insulin that is usually taken every 12 or 8 hours

what most would suggest is that with the help of your nurse, you get the basal insulin right, or you are chasing your tail with bolus.

Basal testing
https://mysugr.com/basal-rate-testing/

 

[Northerner]

Hi Arthur, welcome to the forum 🙂 Erm, has your (former) method been working well for you? If so, why change it? What has been sugested to you by the diabetes nurse is a 'textbook' approach that would normally be used when a person is new to insulin. In practically every case, this would not actually fit with the person's very individual insulin requirements, so changes would need to be made to dosing levels until the desired waking, pre-meal and post meal levels were being regularly achieved.

How long have you been on insulin? Do you know what your HbA1c is? What you are doing is adding in a 'correction' dose of fast acting insulin when you inject before you eat, so that you can achieve a good reading after eating and before the next meal. The aim of 5-7 mmol/l on waking or pre-meal is what we are asked to aim for, I suspect that the 8-10 suggested to you is partly to safeguard you from low blood sugars, having changed your doses. Do you have any follow-up appointments with her to tweak the doses?

Have you been taught carb counting and/or been on a course where insulin ratios are discussed?

I think you have been given too many changes at once, to be honest. What you need to do first of all is a basal test - this will determine how well your Humulin is covering you for the times when you are not eating: your liver gradually trickles out glucose in order to keep your body supplied with energy all the time, to keep your heart, lungs, digestive system etc. working when you are not supplying energy from food - you need insulin that works slowly, over 24 hours, to help process this. A basal test should show, if the dose of Humulin is set correctly, that your levels stay nice and steady, and within range throughout the day and night - ideally in the 5-7 range. Only when this is sert correctly can you be sure that any fast-acting insulin is 'working' only to cover the carbohydrates in your food. Have a read of the following to understnad how to do a basal test (it is written for people on insulin pumps, but the same principles apply):

https://forum.diabetes.org.uk/boards/threads/basal-testing-made-easy.19060/

Once you have got your basal dose set correctly you can start working out your meal doses of fast-acting, and you do this by working out your insulin to carbohydrate ratio. This means working out how much insulin you need in order to 'cover' 10g of carbohydrate, and is known as carb counting.For a simple explanation of this, please have a read of the following:

https://shop.diabetes.org.uk/usr/downloads/Carbs-Count-2012-reduced.pdf

Once you have worked out your insulin to carb ratios you can apply this to any meal by calculating how many carbs are in the meal, then injecting the appropriate dose to 'cover' this 🙂

Finally, 'correction' doses are doses of fast acting insulin that you use when your levels are too high to bring them back into range. In theory, if your basal is set correctly and you get your meal doses correct you shouldn't need to do many corrections at all. The correction factor is the number of mmol/l that one unit of fast-acting insulin will lower your levels by. For me one unit of fast acting insulin will bring my levels down by 3 mmol/l, so if I was 12 mmol/l and wanted to bring myself down to 6 mmol/l I would inject a 'correction' of two units 🙂

People vary so much in their requirements you need to find your own particular requirements by lots of testing, tweaking and experience.

I hope this makes some sort of sense and I haven't bored you to sleep! 😱 😉 I don't think what the nurse has told you is wrong, but it doesn't sound like she has explained why you have been asked to make the changes and what you are trying to achive.

Please let us know if you have any questions 🙂