Tracking insertion and removal times of a continuous glucose monitoring sensor

A continuous glucose monitoring (CGM) system comprising:

• a sensor configured to be inserted into skin of a user and to generate electrical signals indicative of a glucose level;
• a first memory having an identifier stored therein identifying the sensor;
• a second memory configured to store therein a plurality of sensor identifiers;
• a real-time clock;
• and
• a processor in communication with the first and second memories and the real-time clock, wherein the processor is configured to execute computer instructions to:
• read the identifier stored in the first memory;
• determine whether the identifier matches any previously-stored identifier in the second memory;
• store the identifier and an insertion time stamp in the second memory in response to the identifier not matching any previously-stored identifier in the second memory, the real-time clock used to generate the insertion time stamp;
• obtain a reinsertion time using the real-time clock in response to the identifier matching a previously-stored identifier in the second memory;
• and
• determine whether the sensor has exceeded a predetermined maximum removal time limit using the reinsertion time.

A method of tracking insertion and removal times of a continuous glucose monitoring (CGM) sensor, the method comprising:

• reading an identifier of the sensor from a sensor unit memory via a processor executing computer instructions in response to activation of CGM;
• determining whether the identifier matches any previously-stored identifier in a second memory;
• storing the identifier and an insertion time stamp in the second memory in response to the identifier not matching any previously-stored identifier in the second memory;
• obtaining a reinsertion time in response to the identifier matching a previously-stored identifier in the second memory;
• determining whether the sensor has exceeded a predetermined maximum removal time limit using the reinsertion time;
• and
• stopping operation of the CGM in response to determining that the sensor has exceeded the predetermined maximum removal time limit.