Continuous glucose monitoring (CGM) systems use a sensor under the skin to check glucose levels in tissue fluid. The sensor stays in place for several days to a week and then must be replaced. A transmitter sends information about glucose levels via radio waves from the sensor to a pager like wireless monitor. The user must check blood samples with a glucose meter to program the devices and is recommended to do so occasionally to ensure the senor is accurate.
CGM systems are more expensive than conventional glucose monitoring, but they may enable better glucose control. CGM devices produced by Abbott, DexCom, and Medtronic have been approved by the U.S. Food and Drug Administration (FDA) and are available by prescription. These devices provide real-time measurements of glucose levels, with glucose levels displayed at 5-minute or 1-minute intervals. Users can set alarms to alert them when glucose levels are too low or too high. The Endocrine Society recommends that adults with T1DM and HbA1c levels less than 7.0% should use RT-CGM devices if they can use them on a nearly daily basis. It also says: “Pediatric, adolescent, and adult outpatients with T1DM and HbA1c levels of 7.0% or more should use RT-CGM if they are able to use these devices on a nearly daily basis.” It did not recommend the use of these devices in acute care settings.
When comments on this guideline appeared, the issue of training of patients and providers in this fairly complex management system had come up. There remain concerns that training may not be adequate and that using these devices in patients who are not fully committed may decrease their effectiveness.
David C. Klonoffat al, Continuous Glucose Monitoring: An Endocrine Society Clinical Practice Guideline, JCEM 96 (10): 2968
J Hans DeVries Continuous glucose monitoring: coming of age? Eur J Endocrinol 2012 166: 1-4
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