Modeling and Simulation of the Local Electric Fields at Stimulation Needles in Human Tissue for Regional Anesthesia

This work deals with the modeling and simulation of the electrical fields in human tissue, arising from the stimulation of nerves in regional anesthesia. Appropriate simplifications are made for chemical and electrical processes to generate a 3D model of a stimulation needle within the tissue. Electrical properties, such as conductivity and permittivity, of the tissues are defined and their influence regarding the local electric field around the needle tip is examined. Finally, the efficacy of a stimulation needle in stepwise more complex and realistic models of human tissue is described. The main purpose of this work is to establish a basic approach of working with such models and to use numerical field simulation to obtain a deeper understanding of the electric situation around the needles typically used in regional anesthesia.