Dexcom G5 Mobile - 7.3 Calibration Overview

Dexcom G5 Mobile System User Guide
106Calibration
Precaution
Do: Enter the exact BG value displayed on your BG meter within five minutes of a
carefully performed fingerstick measurement.
Why: Entering the wrong BG values, or waiting more than five minutes before entry,
might affect sensor accuracy.
Consequences: Missing a severe low or high blood glucose event or making a
treatment decision that results in injury.
Precaution
Do: Only use fingerstick measurements from your BG meter for calibration.
Don’t: Never use alternative site BG values such as blood from palms, forearms, etc.
Why: Alternative site BG values are different from a fingerstick BG value and may not
reflect most recent BG value.
Consequences: Missing a severe low or high blood glucose event or making a
treatment decision that results in injury.
7.3 Calibration Overview
What Is a Calibration?
As you learned earlier, the sensor glucose readings come from measuring the glucose found
in fluids between your cells (interstitial fluids). Although blood and interstitial fluids are
similar, sensor glucose readings can be different between your fingerstick and your CGM.
Calibration provides a comparison, or measurement, between your BG meter’s fingerstick
measurement and the sensor’s glucose readings, allowing alignment between the sensor and
BG meter.
Your BG meter “teaches” the sensor your glucose values through calibration. Just like a clock
can need adjusting, calibrations allow your CGM to adjust to your body.