Nighttime With Threshold Suspend

Diagnosed with diabetes at the age of 8, before blood glucose (BG) meters, Donna Winchester monitored her BG through regular urine tests several times a day. Over 35 years later, she is now managing her diabetes with the MiniMed 530G with Enlite. Recently, Donna had a nighttime experience with Threshold Suspend she shares with us today.
I find myself ignoring my alarms on my MiniMed 530G insulin pump (especially in the middle of the night when I am sleeping). While I know this is not the best use of the features on my pump, I also battle with doing what is right, because sometimes it just stinks to be interrupted by alarms.
Recently, one night, I was receiving several low blood glucose alerts for over an hour, and a low predicted alert, but simply quieted them and went back to sleep. Then, the pump went into Threshold Suspend, screaming at me. The Threshold Suspend feature automatically stops insulin delivery when my sensor glucose value reaches a preset low limit (mine is set to 65 mg/dL). The alarm jarred me awake, and after some time, I finally got myself out of bed to test my blood glucose (BG). As soon as I sat up, I realized I was very low.
When I got up, I struggled to get down the hall to test my BG, and when I did, my meter confirmed I was indeed low. My BG was 42 mg/dL. By the time I tested and treated my low, my insulin had already been suspended for over an hour. After treating my low, my BG came back up and I resumed the insulin delivery.
I was thankful for the Threshold Suspend because it had already stopped my insulin (which I was not able to think of at the time). If that hadn’t stopped, I would have continued receiving insulin, which would’ve made me much worse. Thanks to the pump handling the suspension of insulin, I was able to focus on treating my low BG. I was in the pre-convulsion fog, but managed to take some glucose tabs, and within 15 minutes, I was where I needed to be. I avoided the convulsions.
I vowed to not complain about the midnight alarms after seeing that it did what it was supposed to that night. I can’t promise that I will always respond right away, because it is the nature of this beast, but I am grateful for the help I have with the continuous glucose monitoring (CGM) and Threshold Suspend feature.
IMPORTANT SAFETY INFORMATION
Medtronic Diabetes insulin infusion pumps, continuous glucose monitoring systems and associated components are limited to sale by or on the order of a physician and should only be used under the direction of a healthcare professional familiar with the risks associated with the use of these systems. MiniMed 530G with Enlite is intended for the delivery of insulin and continuous glucose monitoring for the management of diabetes mellitus by persons 16 years of age or older who require insulin.
Pump therapy is not recommended for people who are unwilling or unable to perform a minimum of four blood glucose tests per day. Insulin pumps use rapid-acting insulin. If your insulin delivery is interrupted for any reason, you must be prepared to replace the missed insulin immediately.
The information provided by CGM systems is intended to supplement, not replace, blood glucose information obtained using a home glucose meter. A confirmatory fingerstick is required prior to making adjustments to diabetes therapy. MiniMed 530G with Enlite is not intended to be used directly for preventing or treating hypoglycemia but to suspend insulin delivery when the user is unable to respond to the Threshold Suspend alarm and take measures to prevent or treat hypoglycemia themselves.
Please visit MedtronicDiabetes.com/isi for more details.
WARNING: The Threshold Suspend feature will cause the pump to temporarily suspend insulin delivery for two hours when the sensor glucose reaches a set threshold. Under some conditions of use the pump can suspend again resulting in very limited insulin delivery. Prolonged suspension can increase the risk of serious hyperglycemia, ketosis, and ketoacidosis. Before using the Threshold Suspend feature, it is important to read the Threshold Suspend information in the MiniMed 530G System User Guide and discuss proper use of the Threshold Suspend feature with your healthcare provider.