Bolus Calculator: Example

Here’s what the Bolus Wizard calculator looks like on the insulin pump. The patient would enter his/her current blood glucose value (200 in this example), and if he/she is about to consume a meal, the carbohydrate content of that meal. In this example, the patient first needs a correction bolus. Because the insulin sensitivity factor is set at 50, he/she would require two units for the correction (target = 100). In addition, he/she is consuming 60 grams of food, for which he/she would take a 6 unit bolus based on a 1:10 insulin-to-carbohydrate ratio.

 

The calculation also takes active insulin remaining “on board” into account, so that over-bolusing and resulting hypoglycemia is less of a possibility.

There is still 1 unit of active insulin remaining from the prior injection, which means that if the patient took 8 units then he/she would take 1 unit too many.

The Bolus Wizard calculator therefore recommends 7 units for this bolus. Let's look at the details:

What a Pump is NOT

As many benefits as there are for using an insulin pump, there are many things a pump is NOT.

For instance, a pump is not:

A cure for diabetes.

A substitute for blood glucose monitoring and carbohydrate counting.

As effective as a healthy pancreas.

 

Just putting on an insulin pump will not “magically” make anyone’s blood sugars better or make diabetes easier to live with. Proper training and support in its set up and use are the keys to success.

 

Potential Drawbacks to Pump Therapy

Some potential draw backs to insulin pumping include:

Cost - be sure to ask about a patient’s financial situation, their insurance coverage status for long term pump use. Patients on high deductable plans may have serious difficulty affording a pump or supplies at eh start of their contract year.

 

Learning Curve - it takes roughly 6 weeks for  a new pump user to become comfortable with using their device, get settings dialed in and begin to see real benefits to pump use. This is a very frustrating time and being “over sold” that a pump is going to “make everything better” makes this frustration that much worse

 

Extra Testing - Risk of Ketosis & DKA because we do not have long acting insulin in our bodies when pumping, should we have a pump failure, run out of insulin, disconnect or in any other way not be receiving insulin we have roughly 3 hours before there is no longer enough active insulin in the body to prevent ketone production. This means that pump therapy’s biggest safety risk is an increased risk of DKA. However this risk can be minimized with appropriate education and use of ketone testing for unexplained high blood sugars, on sick days, or in times of intense physical stress.

 

Weight Gain Potential – some patients find that their weight increases when pumping, part of this may be an increase in blood sugar control that is requiring more insulin delivery. It may also be a newfound freedom to explore more foods in quantities that were once “off limits”

 

Skin Irritation – prolonged exposure to adhesives can cause skin irritation and preventing this with good skin car and  adhesive removal techniques is important for long term use. There are also many ways to reduce irritation should they become problematic.

 

Inconvenience - Wearing a device, or even multiple devices with cgm use, can be inconvenient at times.

 

Visibility - Some people are not comfortable wearing a device that can be seen to “identify” them as a person with diabetes. Likewise wearing a device may bring up body image insecurities or fears in some users.

 

Time/Discomfort of Set Changes - Though “pokes” are less frequent with infusion sets, they are significantly larger needles and so discomfort may be a barrier to pump use. Timing set changes to not interrupt ones day, work, or sleep is also key to successful pump use.

 

Teaching & Follow-Up Required - To get the most out of pump therapy knowledgeable and ongoing education and support is needed--particularly as pump technologies continue to evolve, a patient who has been pumping for 20 years may find themselves struggling with a new system.