Sep 13, 2023

What is high blood sugar and why is it dangerous?

For people living with diabetes, managing blood sugar is a balancing act 

If you’re experiencing excessive thirst or hunger, frequent urination, tiredness, and blurred vision, you could be having a hyperglycemic – also known as high blood sugar – episode.   

Jen McVean
Jen McVean, M.D.

And that can be dangerous for people living with type 1 diabetes, a disease where the body attacks beta cells in the pancreas that make insulin.  

Hyperglycemia that lasts, even if it's not severe, can lead to health problems that affect the eyes, kidneys, nerves, and heart. If it goes untreated for too long, it can become severe and cause serious health problems that require emergency care, including a diabetic coma.  

We consulted Jen McVean, M.D., a pediatric endocrinologist and Medical Affairs Sr. Director at Medtronic, to learn the warning signs of high blood sugar – and how to avoid them. 

Often, we place focus on the dangers of low blood sugar. And while that’s needed, a focus on high blood sugar levels is just as important. Like anything with diabetes, it’s a balancing act.  

Staying within the target blood glucose range — between 70 and 180 mg/dL for most people — can be exhausting and overwhelming.  

Eating a healthy diet with plenty of fruit and vegetables, maintaining a healthy weight, and getting regular physical activity can all help, according to the Centers for Disease Control and Prevention (CDC).  

Experts also recommend eating at regular times, not skipping meals, and keeping track of blood sugar levels – all things that can add to the burden for someone living with diabetes.  

But new technology is helping to ease some of that burden, McVean said. Medtronic’s MiniMed ™ 780G System with Meal Detection™ technology* automatically adjusts and corrects sugar levels every 5 minutes to help prevent highs and lows.§ 

A key component of the MiniMed 780G system U.S. pivotal trial was testing two different basal set points—one at 120 mg/dL and one at 100 mg/dL, the lowest target in any automated insulin pump on the market1 and one that more closely mirrors the average glucose of someone not living with diabetes.  

Among adolescents, the number of participants hitting 70% TIR rose from 18% at baseline to 59% overall.  

“The results speak for themselves,” McVean said. “They show just how powerful real-time autocorrections can be.” 

Read more about thebenefits of using pump therapy as first-line diabetes treatment. 


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*Taking a bolus 15 – 20 min before a meal helps to keep blood sugar levels under control after eating. 
Refers to auto correct, which provides bolus assistance. Can deliver all auto correction doses automatically without user interaction, feature can be turned on and off. 
§ Refers to SmartGuard™ feature. Individual results may vary
1. Arrieta A, et al. Diabetes Obes Metab. 2022;10.1111/dom.14714 



The MiniMed™ 780G system is intended for continuous delivery of basal insulin at selectable rates, and the administration of insulin boluses at selectable amounts for the management of type 1 diabetes mellitus in persons seven years of age and older requiring insulin as well as for the continuous monitoring and trending of glucose levels in the fluid under the skin. The MiniMed™ 780Gsystem includes SmartGuard™ technology, which can be programmed to automatically adjust insulin delivery based on the continuous glucose monitoring (CGM) sensor glucose values and can suspend delivery of insulin when the sensor glucose (SG) value falls below or is predicted to fall below predefined threshold values. 

The Medtronic MiniMed™ 780G system consists of the following devices: MiniMed™ 780G insulin pump, the Guardian™ 4 transmitter, the Guardian™ 4 sensor, One-press serter, the Accu-Chek™ Guide Link blood glucose meter, and the Accu-Chek™ Guide test strips. The system requires a prescription from a healthcare professional. 

The Guardian™ 4 sensor is intended for use with the MiniMed™ 780G system and the Guardian 4 transmitter to monitor glucose levels for the management of diabetes. The sensor is intended for single use and requires a prescription. The Guardian™ 4 sensor is indicated for up to seven days of continuous use. 

The Guardian™ 4 sensor is not intended to be used directly to make therapy adjustments while the MiniMed™ 780G is operating in manual mode. All therapy adjustments in manual mode should be based on measurements obtained using a blood glucose meter and not on values provided by the Guardian™ 4 sensor. The Guardian™ 4 sensor has been studied and is approved for use in patients ages 7 years and older and in the arm insertion site only. Do not use the 

Guardian™ 4 sensor in the abdomen or other body sites including the buttocks, due to unknown or different performance that could result in hypoglycemia or hyperglycemia. 

WARNING: Do not use the SmartGuard™ feature for people who require less than 8 units ormore than 250 units of total daily insulin per day. A total daily dose of at least 8 units, but no more than 250 units, is required to operate in the SmartGuard™ feature. 

WARNING: Do not use the MiniMed™ 780G system until appropriate training has been received from a healthcare professional. Training is essential to ensure the safe use of the MiniMed™ 780G system. 

WARNING: Do not use SG values to make treatment decisions, including delivering a bolus, while the pump is in Manual Mode. When the SmartGuard™ feature is active and you are no longer in Manual Mode, the pump uses an SG value, when available, to calculate a bolus amount. However, if your symptoms do not match the SG value, use a BG meter to confirm the SG value. Failure to confirm glucose levels when your symptoms do not match the SG value can result in the infusion of too much or too little insulin, which may cause hypoglycemia or hyperglycemia. 

Pump therapy is not recommended for people whose vision or hearing does not allow for the recognition of pump signals, alerts, or alarms. The safety of the MiniMed™ 780G system has not been studied in pregnant women, persons with type 2 diabetes, or in persons using other anti-hyperglycemic therapies that do not include insulin. For complete details of the system, including product and important safety information such as indications, contraindications, warnings and precautions associated with system and its components, please consult  and the 

appropriate user guide at 

Important Safety Information: Extended Wear Infusion Set (EIS) 
The Extended Infusion Set is indicated for up to 7 days of wear for the subcutaneous infusion of insulin from an infusion pump. It is NOT indicated for intravenous (IV) infusion or the infusion of blood or blood products. Inaccurate medication delivery, infection and/or site irritation may result from improper insertion and maintenance of the infusion site. Before insertion, clean the insertion site with isopropyl alcohol. Remove the needle guard before inserting the infusion set. If using this infusion set for the first time, do the first set-up in the presence of your healthcare professional. Do not leave air in the infusion set. Prime completely. Check frequently to make sure the soft cannula remains firmly in place as you may not feel pain if it pulls out. The soft cannula must always be completely inserted to receive the full amount of medication. If the infusion site becomes inflamed, replace the set, and use a new site until the first site has healed. Replace the infusion set if the tape becomes loose, or if the soft cannula becomes fully or partially dislodged from the skin. Regularly replace the infusion set as indicated in the instructions for use, or per the insulin labeling, whichever duration is shorter. For more details, see https://