Algorithm Sensor Augmented Bolus Estimator for Semi-Closed Loop Infusion System

An infusion system for infusing a fluid into the body of a patient, the system comprising:

• a sensor system that includes a sensor for monitoring blood glucose concentration of a patient, and produces at least one sensor signal, which is representative of the blood glucose concentration of the patient, and wherein the at least one sensor signal is used to generate at least one sensor signal input;
• a controller, wherein the controller uses the at least one sensor signal input to determine at least one sensor-derived blood glucose trend, and wherein the at least one sensor-derived blood glucose trend is used to determine blood glucose levels at a predetermined time in the future;
• and
• a delivery system that infuses a fluid into the patient, wherein operation of the delivery system is affected by commands from the controller and the patient,
• wherein the controller suspends fluid delivery if the at least one sensor-derived trend yields at least one blood glucose level reading that is below a predefined low shutoff threshold.