Model reference adaptive control with constraints for postoperative blood pressure management

An approach for adaptive control of blood pressure using sodium nitroprusside is presented. A modified stochastic model reference adaptive control algorithm with a time-varying reference model is developed and used for this purpose. An automatic adjustment of the reference model is proposed in order to optimize the performance of the closed-loop system while meeting clinical constraints imposed on the infusion rate and the mean arterial pressure. Extensive computer simulations show the robustness of the proposed controller in the presence of relatively high noise levels, over the full range of plant parameters and for large parameter variations.