Steps Towards a Closed-Loop System for Blood Pressure Control

Abstract

Management of blood pressure in the operating room is currently done manually by anesthesiologists. Poor blood pressure management has been linked to poor postoperative outcomes. As such, development of a closed-loop system for blood pressure control is warranted, given it produces improved patient care. In this work, we present a breakdown of the interdisciplinary problem of blood pressure control, and initial steps towards solving this problem. Previous attempts at solving this problem fall short in their lack of incorporation of mechanistic cardiovascular models. Our novel contribution is a closed-loop system for blood pressure control built with explicit incorporation of cardiovascular system mechanisms. We first build a pharmacokinetic-pharmacodynamic model of the cardiovascular system in response to cardiovascular system actuators, vasoactive drugs. We use two actuators in our framework: phenylephrine, to raise blood pressure, and nicardipine, to lower blood pressure. We emphasize our use of the two-element Windkessel model in our pharmacodynamic component. We then build a model predictive control framework given this pharmacokinetic-pharmacodynamic model, and present preliminary control simulation results. Our simulation results indicate feasibility of our model-based control design in upcoming experimental studies. In the future, we seek to validate this control framework in vivo, and ultimately improve patient care in operating rooms through optimized blood pressure management.