Artificial Pancreas Coupled Vital Signs Monitoring for Improved Patient Safety

This paper describes an improved design of artificial pancreas, which takes into account the physical parameters of human body for detecting hypoglycemic state of diabetic patients. In diabetes mellitus, failure in endogenous insulin production requires exogenous infusion of required drug amount. Traditionally, a closed-loop blood glucose level (BGL) control system includes a patient, continuous glucose monitor, controller and an insulin pump as the actuating device. Such systems are not perfectly safe to use as an overdose due to late action of insulin and/or delay in reading sensor data may lead to dangerously low blood sugar levels (hypoglycemia). Our design incorporates vital signs such as electrocardiogram, heart beat rate, electroencephalography and skin resistance for early detection and avoidance of hypoglycemia state. The objective is to securely control BGL of a patient suffering from diabetes and to prevent the harmful state of hypoglycemia. A typical proportional integrate derivative controller is designed for keeping glucose level inside the desired 'safe' range under normal conditions. Once hypoglycemia is detected, a specified amount of glucagon is infused into the patient's body. The simulations have shown that patient safety can be improved through this strategy. In addition, the model-based design of the purposed system is validated by the UPPAAL model checker tool.