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Blood glucose readings
- Thread starter RomaToy
- Start Date
Either because you are rising quickly, the sensor is a bit behind on blood, or because your sensor is a bit off.
D
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How old is your sensor?
I ask because some of us find it takes a couple of days for our body to get used to an alien object in our arm which causes the readings to be random until the sensor has bedded in.
For this reason, I apply my new sensor a day or two before my old one expires.
What was happening to your blood sugars at the time?
CGMs read interstitial fluid not blood. This runs about 15 minutes behind blood sugar readings. The algorithm used in Libre to convert the interstitial fluid values to blood glucose "predicts" the current reading by extrapolating the current trend. If your trend changed in the last 15 minutes, the prediction will be off and over estimate a low (or high). For example, if you treated a low, Libre will assume your levels are still falling after they start climbing.
This is why it is important to use finger pricks to check for hypo recovery.
Where you lying on the sensor?
All CGMs suffer from compression lows. These are false lows due to pressure being applied to the sensors such as when you lie on it which can be annoying if it wakes you in the night for this reason.
This is one reason why it is important to test all lows before treating (unless you feel obviously hypo).
If none of the above and your sensor is constantly reading inaccurately, it could be faulty. In this case, you need to report it to Abbott.
I ask because some of us find it takes a couple of days for our body to get used to an alien object in our arm which causes the readings to be random until the sensor has bedded in.
For this reason, I apply my new sensor a day or two before my old one expires.
What was happening to your blood sugars at the time?
CGMs read interstitial fluid not blood. This runs about 15 minutes behind blood sugar readings. The algorithm used in Libre to convert the interstitial fluid values to blood glucose "predicts" the current reading by extrapolating the current trend. If your trend changed in the last 15 minutes, the prediction will be off and over estimate a low (or high). For example, if you treated a low, Libre will assume your levels are still falling after they start climbing.
This is why it is important to use finger pricks to check for hypo recovery.
Where you lying on the sensor?
All CGMs suffer from compression lows. These are false lows due to pressure being applied to the sensors such as when you lie on it which can be annoying if it wakes you in the night for this reason.
This is one reason why it is important to test all lows before treating (unless you feel obviously hypo).
If none of the above and your sensor is constantly reading inaccurately, it could be faulty. In this case, you need to report it to Abbott.
