Meal Announcement with Insulin Pumps
Yes, you must announce meals to the insulin pump by entering the amount of carbohydrates you plan to eat so the pump can calculate and deliver the appropriate mealtime bolus dose of insulin. 1, 2
How Meal Boluses Work
The insulin pump requires user input before eating to calculate the correct insulin dose:
- Before consuming food, you must inform the pump of your current blood glucose level (measured via fingerstick) and the amount of carbohydrate to be ingested in grams 1
- The pump's onboard calculator then determines the bolus dose based on your preprogrammed carbohydrate-to-insulin ratio and insulin sensitivity factor 1, 2
- The carbohydrate-to-insulin ratio defines how many grams of carbohydrate are covered by 1 unit of insulin (for example, with a 1:10 ratio, every 10 grams of carbohydrate requires 1 unit of insulin) 1
The Calculation Process
The pump performs a multi-step calculation when you announce a meal:
- The bolus dose accounts for both the carbohydrate load you're about to consume and any correction needed for pre-meal hyperglycemia above your predetermined target 1
- The pump also factors in "insulin on board" from previous doses to prevent insulin stacking and hypoglycemia 1
- You can accept the calculated dose or override it based on anticipated variations in insulin sensitivity (such as during exercise or stress) 1
Why This Cannot Be Skipped
Failing to announce meals will result in severe hyperglycemia because the basal rate alone only provides approximately 50% of your total daily insulin requirement and is designed solely to maintain euglycemia during fasting states 1, 2. The basal infusion prevents ketosis but does not provide sufficient insulin to handle carbohydrate absorption from meals 1.
Timing Considerations
- Bolus insulin should be administered at or just before meal times 1
- For high-fat or high-protein meals, you may need to deliver 24-75% additional insulin beyond the standard carbohydrate calculation, ideally using a combination bolus pattern with at least 60% delivered upfront 3
- Administering the bolus 15 minutes before eating may improve postprandial glucose control for fat and protein-containing meals 3
Common Pitfalls
The most critical error is eating without announcing the meal to the pump, which will cause blood glucose to rise rapidly since only basal insulin is running 1. Additionally, inaccurate carbohydrate counting leads to incorrect bolus doses—overestimation causes hypoglycemia while underestimation results in hyperglycemia 1.