I feel silly asking this question but it’s been so long since I’ve been on injections I don’t know the answer
. If you take shots, when dosing for meals so you use a sliding scale, or get as close as you can with a carb ratio?
Dorie @wadawabbit , I don’t currently utilize management method currently known as MDI - originally referred to, as you may recall, as IGC or Intense Glucose Control. I used as close to exact as possible calculations rather than hit=or-miss pre-printed sliding scale that slides over two critical factors for proper insulin dosing.
The formular we(*) developed in its most basic written arithmetic format is A+B-C, which I calculated in my head, and which form the underlying theory of many dose calculators [such as in pumps] in use today. I’ll try to explain this formular:
A = (BG-Target) / ISF [this value can be either negative or positive}
B = Total Carbs x I:Cr
C = Estimated bolus still active
NOTE “we(*)”: In 1975, I was recruited, or shall we say assigned, by the Medical Director of Joslin Clinic to work with a Joslin diabetes scientist in an attempt to develop better methods for diabetes management. Up to that period, insulin dosing by using a single daily injection (sometimes split into two half doses per day) of Long-Acting insulin [not to be confused with long0duration background formulations which became available in 2002 with Lantus] such as NPH or the just arrived Humulin-N. The success of our work was proven by the worldwide DCCT Study of the 1980s. This method was developed before the arrival of BG meters that produced a numerical value - we used our best guess on the shade of green showing on the reactive strip.
1 Like
Think Like a Pancreas
Gary Scheiner, MS, CDCES
4th ed., p. 182-183Chapter 7 In Search of the Perfect Bolus
There are many unusual factors that can influence bolus requirements; several will be covered in the next chapter. For our purposes here we will focus on the five primary factors that should be considered when determining bolus doses:
- the amount of carbohydrates in the meal or snack
- the glucose level at the time of the meal or snack
- the direction the glucose is headed
- the amount of insulin still remaining from previous boluses
- the amount of planned (or recently completed) physical activity
If you are into math (you know who you are - your favorite shows are The Big Bang Theory and whatever the latest iteration of Star Trek happens to be), boluses are calculated as follows:
Bolus dose = (food dose + correction dose + rate-of-change adjustment - insulin on board) x activity adjustment
When I was on MDI earlier this year this is what I did, except I’d memorized the food doses so I didn’t use a carb ratio to math the food dose.
Are you working on your what to do when your pump fails plan or got something else going on?
Thank you Dennis. I’ve found you to be an incredible wealth of information but had no idea you were involved in what have become standards of treatment now! I’ve never been a history buff but it is fun to be reminded of the days of good old NPH (and if you don’t mind I’ll take you even further back to beef and pork) and those clinitest and acetest chemistry kits we kept in our bathrooms.
I don’t need to preface this by saying “it’s been a long time” but as best I recall for a while there I was on a sliding scale of NPH based on my morning numbers and a standing dose for meals. But when we learned about counting carbs I can’t recall if it was customary to use a sliding scale for those, or to calculate the dosage for the carbs in your head and take inject the closest (4 units if it came to 4.2) - or what people on shots do now?
Thank you for the stroll down memory lane!
Hi @spdif ! When I’m on other social media and refer to dosing I naturally refer to carb ratios since I use a pump - but I don’t know if that applies to people on injections. No issues here - ilet is serving me well - I’m just trying to figure out how to frame comments.
Dorie, what I should have mentioned, we developed this method before the arrival of BG meters that produced a numerical value - we used our best guess on the shade of green showing on the reactive strip.
All NPH [and Regular, Lente, UltraLente, etc.] long-acting insulin formulations were porcine/bovine derived insulins prior to development of recombinant DNA [rDNA] formulations [Humulin-R and Humulin-N were the first] that came in the 1970s and influenced making U-100 the standard strength for insulin. A wee bit of history to go with that, the development of rDNA was assisted by experimentation on the US Space Station.
I’m not sure if I was using anything else prior but the first insulin I can recall taking was pork. At some point beef insulin came along and I switched to that in college when I first heard that pork was considered unclean (sorry, bacon lovers). I recall a couple call iletin and protamine-zinc but never had the pleasure.
Of course initial strength was U40, then came U80 - doing the math was easy as you took half but my mom fretted over whether I would remember (old habits die hard after all). The calculation when U100 came along was a little trickier but we got it. On thing about Type1, it keeps you exercising your math skills - or used to anyway. Dennis, as far as I’m concerned you are our official historian!
1 Like