Continuous glucose monitoring and sensors
What is a glucose sensor?
A glucose sensor is a tiny electrode that measures your glucose levels. It sits under the skin in your interstitial fluid, where cells get oxygen and nutrients, including glucose. Glucose sensors are easily inserted using an automatic insertion device: like many types of infusion sets, a needle is used to insert the glucose sensor. The needle is then removed leaving just the tiny flexible electrode under the skin. The glucose sensor is then connected either to a transmitter so that readings can be transmitted to your insulin pump or monitor, or a recorder for downloading to software once removed.
Do I still need to do fingerstick readings if I use glucose sensors?
Using glucose sensors does not replace the need for fingerstick measurements. You still need to use your blood glucose meter to confirm a continuous glucose monitoring (CGM) reading before treating and to calibrate the CGM system.
What are the highest and lowest glucose alarm thresholds that I can set?
High alarm thresholds can be set as high as 22.2 mmol/L and the minimum low alarm threshold can be set as low as 2.2 mmol/L.
High and low threshold ranges can be customized by the user. You should discuss your personal threshold levels and alert settings with your healthcare provider.
The high and low glucose alarms have to be at least 0.6 mmol/L apart.
For example, if you set your high glucose limit at 10 mmol/L, then you cannot set your low glucose limit greater than 9.4 mmol/L. Conversely, if you set your low glucose limit at 2.8 mmol/L then you cannot set your high limit lower than 3.4 mmol/L.
How long do glucose sensors last? Do they expire?
Each glucose sensor can be worn for up to 6 days at a time. Glucose sensors have a 6 month expiration date from the time they are manufactured. The expiration date is on the outside of the glucose sensor box and on each individual glucose sensor package.
What type of batteries does the transmitter use?
The transmitter has a self-contained battery, which can be recharged using the charger supplied, but cannot be changed. As it has a self-contained battery, the transmitter should be disposed of, or recycled, in accordance with local governing ordinances and recycling guidelines.
What is the warranty of the transmitter?
The MiniLink™ transmitter has a 1 year warranty from date of purchase.
Do I need to refrigerate my glucose sensors?
Our Enlite glucose sensors do not need to be refrigerated. Enlite™ glucose sensor can be stored at temperatures ranging between 2˚ and 30˚Celsius (36˚ to 86˚ Fahrenheit) without the need for cooling. To identify these glucose sensors, look for a temperature graphic on the outside of the individual glucose sensor package, or on the side of the glucose sensor box.
Our glucose sensors have been comprehensively tested to safely withstand extreme hot and cold weather shipping conditions in the “non-refrigerated” shipping boxes.
Glucose sensors must not be frozen.
If you choose to keep your sensors in the refrigerator anyway, allow approximately 15 minutes for the sensor to warm up to room temperature before you use it.
Where should I wear a glucose sensor?
Where you wear your glucose sensor may be influenced by clothing, comfort, individual preference or experience. You may want to avoid recent infusion sites. The Enlite sensor is approved for wear on the abdomen or buttock. While many people choose the abdominal area, some people prefer the upper buttocks, as this location is less likely to be bumped or affected by clothing at the waistline.
See the Enlite User guide for recommended locations of insertion.
On the MiniMed® Veo™, how will I know when the transmitter battery is getting low?
When the transmitter reaches a low battery condition, it will notify the insulin pump or monitor. It will display a "LOW TRANSMTR" notification. From the first "LOW TRANSMTR" notification of a low battery, you have about 5 days of continuous use before the battery is completely depleted. You will then receive a "BAD TRANSMTR" notice which means the transmitter battery has been depleted.
See the Alerts & Alarms section for more information.
What is the operating range between the transmitter and the insulin pump?
The transmitter and the insulin pump must be within approximately 2 metres (6 feet) of each other for wireless transmission to occur.
With my MiniMed® Veo™, what happens when the transmitter and insulin pump move out of range?
If the transmitter and insulin pump are too far apart (more than 2 metres or 6 feet), an alert will sound and either a "WEAK SIGNAL" or "LOST SENSOR" message will appear on the screen. The MiniMed® REAL-Time insulin pump and continuous glucose monitoring (CGM) system allows to set the period of time the insulin pump will wait before alerting you of a failed reception of CGM data from the transmitter to the insulin pump. The delay can be set between 5 and 40 minutes. The default setting is 30 minutes.
The transmitter holds 40 minutes’ worth of memory; if the transmitter and insulin pump are too far apart for longer than 40 minutes, reports will have a "data gap" where information is missing during this time period.
Is the radio frequency from my MiniLink™ transmitter harmful to me in any way?
The MiniLink™ transmitter sends very small transmission “bursts” which are not harmful*.
*Data on file.
How do you turn off the transmission from the MiniLink™ transmitter to the insulin pump?
The transmitter begins transmitting data as soon as it is connected with the glucose sensor. It also transmits data when the CGM on the insulin pump is off. Therefore, you should disconnect the glucose sensor from the transmitter. The glucose sensor can remain inserted.
Why do I have to calibrate?
Calibrating your system is like setting the time on your watch and adjusting it occasionally to make sure it’s still showing the correct time. To initialize a glucose sensor, you need to enter a meter reading to give the system a starting point. You will then need to enter at least 2 meter readings a day – once every 12 hours. This aligns the glucose sensor with the meter so that CGM readings are representative of your blood glucose (BG) level.
How often do I have to calibrate the MiniMed® Veo™ insulin pump?
Calibration is only necessary when you are using the CGM function of your insulin pump. The MiniMed® Veo™ insulin pump must be calibrated a minimum of twice a day (once every 12 hours) by entering a fingerstick value into the insulin pump. However, for best results, you can calibrate 3 to 4 times per day, with the calibrations spread throughout the day at periods when glucose is not changing rapidly. This will allow more accurate glucose detection at all levels.
When should I calibrate the MiniMed® Veo™?
It is best to calibrate when your blood glucose is not changing rapidly. We recommend that you calibrate on a routine schedule, for instance when you first wake up, before a meal, or before your bedtime snack. Try to find a time during the day when your blood sugar is stable as it is important to calibrate when glucose values are not changing rapidly. For example, glucose is more stable before a meal; do not calibrate after a meal, because it is more likely that glucose will change rapidly to adjust for the food being digested.
Visit myLearning online product modules for more information at www.medtronicdiabetes.ca/mylearning
The CGM readings do not match my meter readings. Should I be concerned about this?
BG meters take glucose readings from plasma blood whereas sensors take readings from interstitial fluid. Most of the time glucose travels first to your blood and then to your interstitial fluid. Because of how glucose travels your BG meter readings and sensor glucose readings will rarely match exactly. This is quite normal.