Bolus Calculations Part II

Think Like a Pancreas Chapter 7, Your Cheat Guide!

Part II

So, how sensitive are you? 

Does the Notebook make you cry? Do kittens make you warm inside? 

Just kidding.

How sensitive to insulin are you?

There are many variables that increase and decrease your sensitivity to you insulin, but when it comes to the basics, see below for the steps to determine how your body responds to your insulin dose:

  1. Test your blood sugar at least four hours after your most recent bolus.
  2. If your sugar is high, calculate and give yourself the correction dose. Go about your usual activities but do not eat or exercise for the next several hours. 
  3. Test your sugars four hours later
  4. Calculate how much your blood sugar came down and then divide by the # of units you gave. This should come close to your sensitivity factor. 

Bolus Insulin On-Board.

Other terminology: Bolus on board, active insulin, insulin remaining/actively working in your body.

Quick fact: The fastest insulin takes about four hours to complete its job (sometimes even longer!)

So what does one do when your experiencing a high blood sugar but still likely have insulin on-board? Aggressively treat? (Im)patiently wait for it to come down? 

Let’s find out.

First, this concept of knowing how much active insulin is in your body is crucial because stacking leads to increased likelihood of low blood sugars. To get a visual idea of (estimated) insulin on board since your last bolus, check out Table 7-6. below: 

Example: Let’s say you injected 6 units of insulin for a 2PM snack and then check your blood sugar at 4pm. According to the table above, you still have 35% of your bolus remaining (6 units x .35 = 2 units). Considering this before your next bolus is important for proper dosing.

Another way to determine how long it really takes for your bolus insulin to finish working is to check your blood sugar every 30 minutes after a correction bolus and see how long it takes for the blood sugar to stop dropping. ***Tip: once you do a correction bolus, do not eat, exercise or give any more boluses until your blood sugar flattens out. 

Example: If you are experiencing a high blood sugar, considering the IOB will help you determine the correct dose for proper balance. Naturally, you may want to bolus/correct. But if you have 2 units on board, you should probably not take anything at all to prevent a low!

HP TIP: All of this can seem very confusing and complicated—which it is. My personal HP suggestion is to keep MINIMAL insulin on board (by mainly eating lower carb), to decrease the likelihood of variability. The more insulin you are injecting, correcting, stacking, etc., the more variable your blood sugars will be. 

Adjustment for Physical Activity—THIS IS A BIGGIE!

As I am sure you already know……insulin sensitivity increases with physical activity. 

In a normal situation, where (1) unit would lower the blood sugar 50mg (2.9 mmoI/I), it might lower it by 75+ (4.4 mmoI/I).  A unit that usually overs 10 carbs, may cover 20!

Anything that has us using our muscles, or has us moving around, can and will affect our response to insulin. The more intense and prolonged the activity, the greater the enhancement in insulin sensitivity. Increased work = your muscles are much more sensitive to insulin.

Your dose for upcoming and previous physical activity can and will vary. Head HERE, and learn how working out can be responsible for falls and rises in blood sugar depending on what kind of workout your doing. 

If you find yourself constantly using food to offset the fear/reality of lows during workout, send me an email! I will be happy to help you calculate and get better control of this, everyone is different and this is no (per usual) one-size-fits-all. 

My go-to method is this: workout first thing in the morning! If your basal dose is correct, you should have minimal to no risk of dropping low. You can workout stress free and focus on really enjoying your workout (working out should NOT be stressful). Depending on the type of work out (click link above to workout post), you may require 1-2 units to offset your liver dumping glucose which can lead to a rise/high blood sugar. 

If you are working out mid-day, you must be mindful of how much insulin you have on board to avoid a low. The less active insulin you have on board, the less variety (risk of the common lows) in your blood sugar.

For high blood sugar prior to exercise, take half the usual correction and drink plenty of water.

If your pre-workout number is extremely elevated, be mindful of ketones. This can be very dangerous and not something to take lightly. 

Inactivity: Sensitivity in Reverse.

Do you sit all day at work and/or class?

Are you intentional about getting some sort of exercise in for your mind and body?

The reality is, the more sedentary you are, the less reactive your body will be to your insulin. The more active you are, the better your body’s response will be! 

If you plan to be more sedentary than usual, like long travel/commute, long school classes, etc. consider taking your bolus up in small increments. 

Bolus Timing. 

TIMING—will make or break your blood sugars. 

Improper timing = unhappy blood sugars.

This is so so hard for me!

Sometimes I just want to snack on blueberries or take a few bites of something… hoping that for some strange miraculous reason my blood sugars won’t rise by much.

Ultimate fail is when I decide to dose while I am snacking….. and 30 minutes later I see my 200+ reading.  I would be lying if this is not bi-weekly occurrence. 

Timing (how soon you can eat after injection) is based on: 

  1. Type of food (glycemic index) 
    1. High GI (will make your blood sugar rise quickly—leaving it difficult to control) example: Fruit juice, soda, waffles, bagel, cereal. 
    2. Medium GI (moderately raising your blood sugar) example: berries, grains, dairy. 
    3. Low GI (containing fiber or large amounts of fat) example: avocado, bacon, greens. 
    4. Click here for a detailed GI food list breakdown:
  2. Your pre-meal blood sugar (i.e. are you working with 75 or 210?)

Check out table 7-12. for a visual on adjustments to bolus timing based on GI and pre-meal blood sugar

Sooooo that was Chapter 7 Part II! What did you think?

I think I need a cookie.

I hope you were able to take away something applicable for your day-to-day blood sugar management. 

Next week is Chapter 8, Welcome to the Real World.