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Insulin pump therapy: Basal rate testing for insulin pump therapy

Insulin Pump Therapy

Basal rate testing for insulin pump therapy

Your first basal rates were estimated by your diabetes team when you started using your insulin pump. Basal rates need to be evaluated again from time to time.

Basal rates can change with:

  • Weight gain or loss
  • Hormone changes
  • Chronic stress
  • Lifestyle changes
  • Pregnancy

Your basal rates may need to be evaluated again if:

  • You have more than 2 high or low blood sugar readings a day.
  • You miss a meal and your blood sugar goes low.
  • Your blood sugar is consistently high before meals.
  • You will not miss a snack or go to bed without a snack, because you know that your blood sugar will go low.

A basal rate test is done when you haven’t taken any bolus insulin, and when you haven’t had any food for the last 5 hours. This is to find out how much sugar is coming from your liver, and how well your insulin is matched to this sugar at different times of the day.

Your blood sugar should not change more than 1.7 mmol/L over or under your starting blood sugar. For example, if your starting blood sugar was 7.0 mmol/L, then the acceptable range during the test would be 5.3 to 8.7 mmol/L. If your blood sugar goes higher than that, you may need more basal insulin. If your blood sugar goes lower than that, you may be taking too much basal insulin.

General guidelines for basal rate testing

  • Pick a day that has been relatively stress free with no low blood sugars.
  • That day, eat balanced meals. Balanced meals are meals that follow the Healthy Plate Model for Diabetes. This includes ½ of your plate being vegetables, ¼ of the plate being a meat or a protein alternative, and ¼ of the plate being grains or starchy vegetables (carbohydrates).
  • Don’t drink alcohol on that day.
  • Make sure you haven’t eaten for 5 hours before starting the test.
  • Start with a blood sugar in the 5.6 to 8.3 mmol/L range. Don’t continue with the basal rate test if your blood sugar isn’t in this range.
  • Don’t eat or take bolus insulin during the test period.
  • If your blood sugar goes low or high during the test, you didn’t fail the test. It just means that your basal rates need to be adjusted. Stop the test and treat the low or high as you normally would. Then, evaluate the changes that could be made to your basal rates.

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Current as of: October 21, 2020

Author: Primary Care and Chronic Disease Management, Alberta Health Services

This material is not a substitute for the advice of a qualified health professional. This material is intended for general information only and is provided on an "as is", "where is" basis. Although reasonable efforts were made to confirm the accuracy of the information, Alberta Health Services does not make any representation or warranty, express, implied or statutory, as to the accuracy, reliability, completeness, applicability or fitness for a particular purpose of such information. Alberta Health Services expressly disclaims all liability for the use of these materials, and for any claims, actions, demands or suits arising from such use.