A Coupled Model of Glucose Homeostasis From a Fieldbus View

Abstract

Glucose homeostasis is a mechanism to maintain blood glucose levels in a narrow threshold to ensure normal human body functions. A mathematical model to describe glucose dynamic in the blood is developed through five sub-models of the main organs involved in such natural mechanism. In this regard, this paper proposes the integration of the sub-models using as analogy the fieldbus concept in a real chemical plant. In this analogy, the circulatory system is taken as the overall process system and blood as a fluid process entering to each organ and exchanging the glucose, insulin, and glucagon concentrations in blood as the main information. The phenomenological-based semi-physical models were used to describe the roles that each organ performs within the regulation of glucose, insulin, and glucagon in the human body. These organs were modeled as pieces of equipment of a chemical plant. The heart acts as a pump driving the blood, the stomach as a union of pipes of different diameters, the small intestine as a plug flow reactor, the liver is considered as a tank with two immiscible phases, the kidney, pancreas, and other organs as a stirred tank reactor with connections with the circulatory system. On the other hand, the glucose is represented as a process energy, which is consumed or generated by different organs. The integration of the organ models is made in Matlab ®, including 14 sub programs with exit to the circulatory system (concentration of glucose, insulin, and glucagon), one for each organ. Normal values of glucose in blood and some abnormal values representing hyperglycemia were tested in the model. A future work is to improve the code to verify its parameters using real clinical trials.