Abbott FreeStyle Libre 3 Getting Started

The Difference Between Blood Glucose and Interstitial
Fluid Glucose Measurement in Simple Terms
As a safe and simple alternative to traditional blood glucose measurement,
FreeStyle Libre 3 measures your glucose level not in your blood, but via a
filament in your interstitial fluid.
In certain situations, there may be small temporal differences between blood glucose readings
and interstitial fluid glucose readings. This is quite normal since, for example, digested food first
enters the blood stream and then passes into the interstitial fluid.
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However, this small difference is minimized by today‘s technology and interstitial fluid glucose
measurement is therefore an accurate and reliable alternative to blood glucose measurement.
3,4,11,19
The FreeStyle Libre 3 system is a simple and safe alternative to traditional blood glucose
measurement.
3,4,11,19
It also lets you adjust your insulin dosage based on your glucose readings.
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Glucose level
Interstitial fluid
glucose
Blood glucose
Glucose is changing slowly
When glucose levels are
stable, the FreeStyle Libre 3
glucose readings and blood
glucose readings are very
similar.
Glucose is rising quickly
If glucose levels are rising
rapidly, the FreeStyle Libre
3 glucose readings may be
lower than the blood glucose
readings.
Glucose is falling quickly
If glucose levels are falling
rapidly, the FreeStyle Libre
3 glucose readings may be
higher than the blood
glucose readings.
Using the example of a roller coaster, the difference between blood
glucose and interstitial fluid glucose can be easily understood.
Interstitial fluid glucose
(FreeStyle Libre 3 sensor)
Blood glucose
(Fingerstick)
Blood vessel
Filament
Sensor
Skin
8 9

Abbott FreeStyle Libre 3 Specifications

General

Sensor Type	Continuous Glucose Monitoring (CGM)
Sensor Wear Duration	14 days
Connectivity	Bluetooth
App Compatibility	FreeStyle Libre 3 app (iOS and Android)
Data Update Frequency	Every minute
Warm-up Time	60 minutes
Accuracy	MARD (Mean Absolute Relative Difference) of 7.9%
Calibration	Factory calibrated
Battery Life	Sensor lasts for 14 days, no battery replacement required
Data Storage	8 hours of data stored on the sensor
Alerts	High and low glucose alerts
Measurement Range	40 to 400 mg/dL (2.2 to 22.2 mmol/L)