Preliminary Experiments with a PI Controller for Cutting Tissue with an Electrosurgery Unit

Electrosurgery is a surgical procedure that applies a high-frequency electrical current to the patient for specific purposes, such as cutting tissue. Electronic devices usually perform this task in an open loop, where the surgeon establishes the desired voltage, current, or power to perform the cut. However, tissue bioimpedance varies due to many factors, such as anisotropy, temperature, humidity, and frequency, which makes the required load unknown during the process. This paper proposes a closed-loop power regulation scheme based on a PI controller for tissue-cutting tasks. The experiments in animal tissue demonstrate that the proposed scheme guarantees the power supply despite changes in the tissue's bioimpedance. Therefore, the result significantly improves the cutting efficiency compared to open-loop operation.