Theoretical blood glucose control in hyper- and hypoglycemic and exercise scenarios by means of an H∞ algorithm

Artificial Endocrine Pancreas (AEP) is one of the most optimistic approaches in Type 1 Diabetes Mellitus (T1DM) treatment due to the novel technological advances in continuous glucose monitoring, exogenous insulin delivery, and their proofs in clinical assessments. The main goal of AEP is to replace the pancreatic insulin secretion in the blood glucose regulation loop by means of an automatic exogenous insulin in fusion. The joint element between glucose sensing and insulin delivering actions is an automatic algorithm-based decision. In this contribution, there is an H-infinity control algorithm to compute the insulin infusion rate during hyperglycemia, exercise and nocturnal hypoglycemia. In order to mimic the insulin release pattern of a healthy pancreas, a frequency restriction in the insulin in fusion pattern generated by controller was considered in the design. The inclusion of mathematical models of relations between glucose and chosen biosignals in the control loop generates an adequate insulin infusion pattern to compensate blood glucose variations during each metabolic scenario. The proposed automatic algorithm for decision shows good performance in controlling glycemia in metabolic scenarios, avoiding long-term hyperglycemia as well as glycemic disturbances during exercise and nocturnal hypoglycemia, guaranteeing insulin infusion with a delivery pattern closer to that generated by a healthy pancreas. (C) 2009 Elsevier Ltd. All rights reserved.