BALTIMORE — Recent developments and approvals in the diabetes technology space have revolutionized care and glycemic management for type 1 and type 2 diabetes, but patients must be careful to avoid several key mistakes when using insulin pumps and continuous glucose monitoring, according to a speaker at the American Association of Diabetes Educators annual meeting.
“I’ve lived with type 1 for more than 40 years,” Margaret Pellizzari, MBA, MS, RN, CDE, CDTC, program coordinator and assistant nurse manager for pediatric endocrinology at Cohen Children’s Medical Center, Northwell Health, New York, said during a presentation. “When I was diagnosed, we didn’t have any glucose meters. I was 21 years old when I went on my first insulin pump, with a bent needle insertion with no way to disconnect, until they finally came out with disconnect sets for your pump. So, I’m bringing you along the journey, living it, and it’s like, ‘What have you done for me lately?’ Well, now these are really exciting times.”
Today, there are many new updates available in the pump and CGM space for patients with diabetes, including:
(Valeritas) — A once-daily, wearable insulin delivery device that you wear like a patch, the V-Go is designed to provide glucose control without multiple daily injections, Pellizzari said. The V-Go releases a steady rate of rapid-acting insulin for basal control and delivers prandial insulin with the click of a button.
Omnipod Dash (Insulet) — In June, the FDA granted 510(k) clearance for the Omnipod Dash insulin management system, a tubeless insulin pump system that wirelessly connects to a bolus calculator and two smartphone apps for diabetes management. The system features Bluetooth wireless technology to allow connectivity between the color touch-screen personal diabetes manager and the tubeless waterproof insulin pump.
T:slim X2 pump
(Tandem Diabetes Care) — The t:slim insulin pump with the Dexcom G5 mobile CGM integration is the only CGM-enabled pump approved for patients to make treatment decisions without finger-stick calibration, Pellizzari said. In addition, any new features for the t:slim X2 pump approved by the FDA before the end of 2018 will be available to providers and patients via a no-cost download on the computer.
Medtronic MiniMed 670G
— The MiniMed 670G measures glucose levels every 5 minutes and automatically adjusts insulin delivery by administering or withholding insulin. The system includes a subcutaneous sensor, an insulin pump and an infusion patch connected to the pump via catheter to deliver insulin. Although the device automatically adjusts insulin levels, users need to manually request insulin doses to counter carbohydrate consumption at mealtime.
G6 — The Dexcom G6 is a patch device applied to the abdomen and continuously monitors the amount of glucose in body fluid through a small sensor. Real-time glucose readings are transmitted every 5 minutes to a compatible display device that triggers an alarm when blood glucose is not at the correct level. The device should be replaced every 10 days. The latest version requires no finger-stick calibration, allows for 10-day wear and has a thinner transmitter vs. previous versions, Pellizzari said, calling it “revolutionary.”
Connect CGM — The Guardian Connect CGM features the Sensor 3, also used in Medtronic’s hybrid closed-loop system, and was shown to accurately alert patients of 98.5% of hypoglycemic events. It is the first smart CGM system designed to alert patients with diabetes of potential hypoglycemia or hyperglycemia up to 60 minutes in advance. Up to five care partners can use the system to track glucose readings in real time or receive glucose readings via text alerts.
(Abbott) — In July, FDA approved the approved the FreeStyle Libre flash glucose monitoring system, which allows patients with diabetes to wear the sensor up to 14 days with high accuracy. The approval makes Abbott’s CGM the longest-lasting self-applied personal glucose sensor available on the market, with improved accuracy and reduced warm-up time.
— The first-ever fully-implantable sensor (under-the-arm) consists of a fluorescence-based sensor, a smart transmitter worn over the sensor to facilitate data communication, and a mobile app for displaying glucose values, trends and alerts. “You do need to calibrate it twice a day,” Pellizzari said. “It will last up to 3 months, and in Europe it is approved for up to 6 months of wear.”
It is important for diabetes educators to remind patients and their caregivers to rotate the location of their insulin pump or injection site on the body for several reasons, Pellizzari said. These include maintaining healthy tissue, improving insulin absorption and minimizing erratic blood glucoses due to absorption rates. Rotating sites can also avoid scarring or lipohypertrophy, a lump under the skin caused by the accumulation of extra fat at the site of many subcutaneous injections of insulin. Lipohypertrophy can be unsightly, mildly painful and may change the timing or completeness of insulin action.
It is also important to encourage patients to use a new infusion set every 2 to 3 days, and be prepared with extra supplies at all times, she said.
“Last night, before I went out to dinner, I changed my infusion set,” said Pellizzari, who has used an insulin pump for 30 years. “When I pulled out my old infusion set, I had a gusher. Two tissues later, I put a new site in. I don’t know what happened, but this morning my blood sugar was in the 300s, and I had to change it out again today. You need to be prepared, know that these things can happen, and always have your backup supplies.”
To allow for good site rotation, she said patients or caregivers should utilize four sites for injections and pump therapy: the abdomen, arm, thigh and buttocks, using larger injection-site surface areas. Pellizzari recommended patients rotate injections within each site by 1 cm between each injection.
“It is recommended that you use one site for 1 week before moving on to the next site,” she said.
If a patient experiences lipohypertrophy, he or she should not inject into that area until the next exam with a provider, Pellizzari said. Using larger injection zones and non-reuse of needles should also be recommended.
In studies, lipohypertrophy was associated with a 0.55% higher HbA1c, higher rates of unexplained hypoglycemia, hyperglycemia and glycemic excursions, an average 10.1-U higher total daily dose of insulin and increased risk for diabetic ketoacidosis, she said.
“Think about someone who is putting in all of the work to take care of their diabetes,” Pellizzari said. “They are trying to do all the carb counting. They are trying to know what all their blood sugars are, and they’re not rotating their sites and getting lipohypertrophy, and that is causing erratic sugars.”
Additionally, switching injections from lipohypertrophy tissue to normal tissue often requires a decrease in the dose of insulin injection, she said. That amount will vary from one individual to the next and should be guided by frequent blood glucose measurements.
“Reductions often exceed 20% of their original dose,” Pellizzari said. “That’s pretty scary.”
A patient with high blood glucose readings should consider several issues, Pellizzari said, including an infusion set that is not working properly, inaccurate carbohydrate counting, forgetting to bolus and running on a low cartridge.
She said it is important for providers to work with patients and caregivers to make sure they are accurately accounting for carbs and logging correct blood glucose readings, particularly when working with adolescent patients as they prepare to take on more diabetes self-care.
“We need to see what the sugars really are, so we can make the insulin adjustments,” Pellizzari said. – by Regina Schaffer
Pellizzari M. What have you done for me lately? Interpreting pump/CGM data. Presented at: American Association of Diabetes Educators; Aug. 17-20, 2018; Baltimore.
Disclosure: Pellizzari reports no relevant financial disclosures.