For those of you who use a Continuous Glucose Monitor, or think you’d like to, here’s an excerpt from Dr. Anne Peter’s review of Dexcom’s newly available fourth generation, the G4, and MiniMed’s CGM, Enlite, which will be available in the Spring. Dr. Peters is an extremely respected endocrinologist, well known in the diabetes community, who practices at the Keck School of Medicine of the University of Southern California in Los Angeles.
I love that Peters wears the sensors, although she doesn’t have diabetes, to understand what it’s like for patients. With all their advantages, one thing she finds burdens patients is the devices many alarms. Funny, we think of the benefit, alerting us to low and high blood sugar, but not the annoyance factor – I guess unless you wear one, I do not.
Excerpt: With Dexcom G4 continuous glucose monitoring, the patient can easily insert the sensor under the skin — …on the abdomen or the back of the arm. A small transmitter is then placed on top of the sensor. The transmitter sends the interstitial glucose value to the device so the patient can see the blood sugar level. It transmits this information wirelessly every 5 minutes, so a patient can get a sense of whether their blood sugars are going up, going down, or staying the same.
…the new Dexcom G4 is somewhat smaller [than the earlier-generation device]. It is not as wide, similar to an iPhone, and is easy to put in your pocket. It has a pretty good range so that you can be moving around in your house and the signal will still reach the device. A blood sugar level that is 100 mg/dL and is going up may require much different treatment from a blood sugar level of 100 mg/dL that is flat and the patient might be just fine. Or, if a blood sugar level is falling fast, it may mean that the patient needs to ingest carbohydrate to avoid a low. The patient can get a lot of information in real time from this device. Then, in my office, I download the device and interpret the data for the patient so I can help the patient analyze the data retrospectively, so that in real time patients can make more reasonable choices.
…we also have the new MiniMed continuous glucose monitor, the Enlite™ sensor, which is supposed to be available in the spring. This is similarly inserted under the skin and taped down. In most cases, this device is talking to the patient’s insulin pump. The insulin pump has the tubing necessary to give the patient insulin, but now this pump also becomes the receiver for the signals from the sensor. The patient can look at the pump and see what the blood sugar levels are doing.
A lot of patients want the pump to automatically give insulin based on their blood sugar levels, but that is not what happens. This is truly a sensor, and the patient then needs to use the Bolus Wizard [calculator] to interact with the pump to calculate the insulin dose. That coupling of the sensor and pump is part of the development of the artificial pancreas. Substantial research is being done to make pumps that can use continuous glucose monitoring data so that the patient does not have to think as much about diabetes management. [Those advances] are in the future.
For now we have sensors that sense interstitial fluid, giving continuous real-time data, and we have pumps that patients interact with to give themselves insulin. You can couple the MiniMed sensor with the MiniMed pump. The Dexcom device does not interact with a pump, although the manufacturer is working on collaborations with some pump manufacturers.
Peter’s full review appeared in Medscape Diabetes & Endocrinology Jan 25, 2013, “Continuous Glucose Monitoring: Practical Uses in Diabetes.”