Continuous Glucose Monitors (CGMs) track glucose levels throughout the day and night, offering a comprehensive view of blood sugar trends. This technology eliminates the need for frequent fingerstick tests, providing real-time data that helps individuals make informed health decisions.
Typical Sensor Duration
The lifespan of a Continuous Glucose Monitor sensor is predetermined by its manufacturer, typically ranging from 7 to 14 days. For instance, Dexcom G6 and G7 sensors last 10 days, while FreeStyle Libre 2 and 3 sensors provide 14 days of continuous use. Some newer versions are extending this to 15 days.
This pre-set duration is a hard limit; the sensor will cease to transmit data once its programmed period concludes. Using a sensor beyond its recommended wear time is not advised, as it compromises accuracy and reliability.
Factors Affecting Sensor Lifespan
While manufacturers set a specific duration for CGM sensors, various factors can influence whether a sensor lasts its full intended lifespan or fails prematurely. Physical activity and impact, such as accidental bumps, can dislodge the sensor or weaken its adhesive, leading to early detachment. Sensor placement also matters, as areas prone to frequent movement or friction may reduce adherence.
Adhesive issues are a common concern, stemming from factors like skin type, excessive sweating, or improper application. Skin reactions or irritation to the adhesive can also necessitate early removal. Environmental conditions, such as extreme temperatures or prolonged water exposure, can affect the sensor’s performance and adhesive integrity. Additionally, individual body chemistry might influence the interstitial fluid where the sensor measures glucose, potentially leading to unstable readings or sensor failure.
Extending Sensor Adherence
Users can take several steps to help their CGM sensors remain securely in place. Proper site selection is important; choosing an area with some padding, away from bones, scars, tattoos, or areas prone to being bumped, can improve adherence. Cleaning the skin thoroughly with an alcohol wipe and allowing it to dry completely before application ensures the adhesive bonds effectively.
Applying the sensor securely and gently rubbing around the adhesive patch after insertion can enhance its stickiness. For added security, especially for active individuals or those with sensitive skin, using medical-grade overlay patches or adhesive tapes can provide extra protection. These patches can prevent the sensor from snagging or lifting during daily activities, maximizing its wear time.
Sensor Replacement Process
When a CGM sensor approaches its end-of-life, the device typically provides alerts to notify the user. These alerts indicate that the sensor session is nearing its conclusion and a replacement will soon be needed. Once the sensor’s programmed duration is complete, it will stop transmitting glucose data.
To remove an old sensor, it is generally recommended to gently peel the adhesive away from the skin, similar to removing a bandage. Using adhesive remover wipes or oil-based products can help loosen the adhesive and minimize skin irritation during removal. After removal, the sensor and applicator should be discarded according to local guidelines. Applying a new sensor involves selecting a fresh site, cleaning the area, and following the manufacturer’s specific instructions for insertion and activation through the receiver or smartphone app. This process often includes a warm-up period before new glucose readings become available.