How to Use the FreeStyle Libre 3+ Sensor Device
The FreeStyle Libre 3 continuous glucose monitoring system should be applied to the back of the upper arm and requires regular scanning to provide maximum clinical benefit for glucose monitoring.
Application and Setup Process
- The FreeStyle Libre 3 sensor should be applied to the back of the upper arm, which is the FDA-approved site with optimal accuracy 1
- Alternative placement on the upper thigh has shown similar accuracy to the upper arm, while abdominal placement performs significantly worse with unacceptable accuracy 2
- When applying a new sensor, it's recommended to insert it before removing the old one to avoid gaps in glucose data collection 1
- The factory-calibrated sensor does not require fingerstick calibrations, unlike some other CGM systems 3
- Each sensor lasts up to 14 days before requiring replacement 1, 4
Proper Usage for Optimal Results
- For maximum clinical benefit, scan the sensor regularly - at minimum once every 8 hours to capture complete 24-hour glucose data 1
- The sensor continuously measures interstitial glucose levels and provides both numerical glucose readings and trend arrows when scanned 5
- Trend arrows add important context to static glucose measurements, helping predict where glucose levels are heading 5
- The system can be paired with a compatible smartphone app (FreeStyle LibreLink) for convenient monitoring 3
- Data can be shared with healthcare providers through the LibreView dashboard for comprehensive glucose pattern analysis 3
Clinical Considerations and Limitations
- The FreeStyle Libre 3 measures interstitial fluid glucose, which has approximately a 4.5-minute lag time compared to blood glucose 4
- Accuracy remains stable throughout the 14-day wear period, with mean absolute relative difference (MARD) of approximately 8.9% compared to reference blood glucose values 6
- Recent comparative studies show FreeStyle Libre 3 has better accuracy than some other CGM systems throughout the wear period 6
- The sensor is not affected by acetaminophen interference due to its wired enzyme technology with sensing membrane working at very low voltage 3
- However, salicylic acid and ascorbic acid may affect sensor accuracy 3
Troubleshooting and Common Issues
- Early sensor detachment is a common issue, particularly in pediatric populations, requiring special attention to proper application 7
- Accuracy may be slightly lower in younger patients and those with lower BMI 7
- The system should not be used in patients receiving peritoneal dialysis due to potential interference, and should be used with caution in hemodialysis patients 3
- For patients with kidney disease, the sensor readings should be used to assess glucose patterns rather than focusing on specific values 3
Optimizing Clinical Outcomes
- Consistent, daily use provides the maximum clinical benefit for diabetes management 1
- Regular scanning (at least every 8 hours) ensures complete data collection for better glucose pattern analysis 1
- Understanding trend arrows is essential for making appropriate treatment decisions and preventing extreme glucose fluctuations 5
- Maintaining uninterrupted access to sensors is important to avoid gaps in continuous glucose monitoring 1