Continuous Glucose Monitoring (CGM)
Continuous Glucose Monitoring System (CGMS) is a three part system including a Sensor, Transmitter and Receiver. A tiny and discreet Sensor is inserted under the skin to continuously read glucose levels. The Sensor stays in place for about a week and then must be replaced. A Transmitter is attached to the Sensor. It transmits blood glucose information to a separate wireless Receiver. The Transmitter can also send information to an integrated insulin pump or smart phone.
Currently, the FDA requires the CGMS user to check blood glucose (BG) levels via a strip and meter about twice a day. However, newer Sensors and new software has improved the accuracy of CGM to a point where it rivals the accuracy of many BG meters.
As the name implies, CGM technology continuously measures BG levels in the body and provides information a meter cannot, and that is Trends. A BG meter will tell you what your BG is at that moment in time. CGMS will tell you your BG as well, but also tell you if your BG is rising or falling, and how fast it is changing. It will even graph your BG over time so you can more accurately determine how YOUR body reacts to exercise, sleep, the food you eat, when you’re sick, etc.
Some people compare CGMS to individual BG reading to driving a car. Using a BG meter and strips to check your BG 4 times a day (a lot for many diabetics) is like driving down a road and opening your eyes briefly, 4 times a day, to see where you are. CGMS, on the other hand, would be like driving with your eyes open.
The CGMS Sensor is comfortable to wear and is most often worn on the abdomen or upper arm. Some can send BG information to up to 5 different smart phones. Not only is it more convenient to read BG on your smart phone, but parents can monitor their child’s BG while sleeping, playing or at school!
PURPOSE: Blood glucose meters (or monitors) are used to test you blood sugar level. In order for the human body to function normally, the level of sugar in the blood must be within a specific, and narrow range. Blood glucose meters are used by individuals with diabetes to determine how much glucose is circulating in their blood. That information is used to calculate how much insulin or other medications are needed to keep blood glucose levels as close to normal as possible.
METERS: There are many types and brands of blood glucose meters and each model may have different features (see Meters and Test Strips). Pumps It carries a wide selection of Meters including the most popular models. TEST STRIPS: In order for a blood glucose meter to measure the level of sugar in the blood, the blood sample must have a way of getting from the individual to the meter. Blood glucose meters use special strips that collect the blood sample. The strip is then inserted into the meter where it can be analyzed. The strips that are provided with glucose meters have expiration dates and should never be used after expiration. Strips should never be used if they are discolored, wrinkled, torn, cut or altered in any way. Strips are brand-specific and cannot be interchanged or reused; they are also light sensitive and must be protected from light, preferably in the original packaging. Strips may also have a code number associated with a specific supply; this code must be entered into the meter so it can accurately analyze the blood sample.
LANCETS: In order for a blood sample to be analyzed, a sample must be drawn from an individual. A lancet is a small device that has a very thin needle used to “prick” a finger and draw a very small amount of blood. The lancet can be used by itself or inserted into a lancing device. The lancet is inserted into the lancing device, the top is twisted off, placed against the skin and activated (it is spring loaded), thus quickly pricking the skin. Lancets should be used only once and then discarded.
USE: Performing a blood glucose test involves sequential steps and each step relies upon the successful completion of previous steps. Do not take shortcuts. The blood glucose meter must be powered on and calibrated, if necessary. Wash your hands with soap and water to prevent any skin oils from coming in contact with the meter or supplies. The site for drawing the blood sample should also be selected and cleaned with soap and water and allowed to dry. The lancet is inserted into the lancing device. The lancing device is placed directly onto the skin and activated. The first small sample of blood is wiped off and then the finger is gently massaged to collect a blood sample size to saturate the specific area of the test strip. DO NOT SQUEEZE THE BLOOD SAMPLE SITE HARD, as this will cause the blood to breakdown and will drastically affect the blood glucose reading. The test strip is then inserted into the blood glucose meter. The reading will be displayed (some meters announce the reading — see Meters and Test Strips).
Your blood glucose level will change during the day and can be affected by your diet, exercise, stress, illness, and medication. Understanding how to interpret your glucose values is key to your overall health. Make sure you keep your glucose value within the target range set by your physician. Call your physician immediately if your glucose level is below 50, or above 250, or your physician’s recommended glucose levels.
Keeping track of your glucose readings is very important. Your physician needs to know how controlled your diabetes is. Keeping a log is important because it helps you see trends in your glucose values and it helps your physician plan your care. Most glucose meters store a large amount of tests, and many can be downloaded onto a computer. Whichever way you have to track your test results, please do so regularly and consistently.
SITE ROTATION: Your diabetes educator will go over procedures with you for selecting and rotating sensor and blood sampling sites.