Diabetes tips

Overcoming Challenges with Insulin Pump Technology: Strategies to Prevent Rebound Highs and Optimize Blood Sugar Control

October 3, 2023

Reader question: "A big challenge I face in lowering my A1c is that my pump shuts off when it detects or predicts that my blood sugar is dropping too low. As a result, I experience a rebound high. I'm wondering how I can address this issue."

Read on for how Lauren and Coach Brooke respond to this question: 

Lauren: This is a great question and it demonstrates a lot of awareness. Many people treat their low blood sugar and then find themselves going high afterwards, without understanding why. They might think, "I only had 10 carbs, why am I going high? Maybe I need to reduce it to five carbs next time."

However, being aware that this issue is related to the technology is already a step in the right direction.

The main point I want to address here is that many people get frustrated with their technology and think they need to switch pumps because the current one isn't helping them achieve their desired results, or they believe that the newest version of a pump will solve their problems. However, we need to shift our perspective and understand that technology is meant to assist us, but we have the ability to optimize it and make smarter decisions.

Let me give you an example. This morning, I went to the gym and my blood sugar was 113 with a sideways arrow pointing down before my workout. I don't always use the activity mode on my Omnipod five pump because it sometimes leads to a rebound high. However, in this case, I turned it on and set it for an hour. About 45 minutes after finishing my workout, I turned it off and my blood sugar was around 105 with a straight arrow. I knew that if I proceeded with my meal and gave my usual amount of insulin, I would end up high because the reduction in insulin I didn't receive for those 45 minutes would impact me later. So, I added an extra 10 carbs to my pre-meal bolus to counteract this.

This is just one example of how I address this issue. I'm curious to hear your thoughts and if you have any experiences or clients in mind.

Brooke: Absolutely. I love the theme you're highlighting, Lauren. It's important to consider the recommendations our pumps give us in the context of our own lives and experiences. I can relate to this question because I use a Tandem T slim pump with Control IQ. In the first couple of months, I was just following the pump's recommendations to see what I could learn with the technology.

However, I quickly realized that I needed to be even more diligent with my pre-bolus timing before meals and be mindful of the automatic bolus calculations when my blood sugar is on the lower end. I noticed that my pump would reduce my basal insulin and also reduce my mealtime bolus if my blood sugar was around 75 or 80 before a meal. If I had already treated the low with a few grams of carbs, I would essentially be triple treating the low, which would result in a rebound high.

So, it's important to approach this issue with curiosity and explore different factors one by one to prevent the rebound. It could involve giving an extra bolus or adjusting pre-bolus timing.

Lauren: Exactly. In my example, I mentioned using the activity mode, while you talked about the pump shutting off when blood sugar is low. Both cases involve reducing the background insulin. In the past, when we didn't have the automated features of pumps like Control IQ, we had to train ourselves to treat lows differently. Now, we need to adapt and find ways to work with the technology to achieve the best outcomes.

Brooke: Absolutely. I'd also like to add that with the reduction in background insulin on a hybrid closed-loop system, you may not need as many carbs to treat low blood sugar as you did when using a manual mode for your pump. I learned that my usual 15 grams of carbs for low blood sugar would quickly raise my blood sugar to the 180s and 200s. Adjusting to eight grams brought me to around 130.