A μ-synthesis-based approach to automate opioid injection in post-surgery patients

This paper presents a robust control design for the automation of opioid injection in post-surgery patients. Most medical devices in today´s hospitals interact with each other over a network. However, owing to their complexity, these interconnected devices usually lack a reliable automated control system, and are still manually supervised and controlled by a human caregiver. The risk of human caregiver errors remains high during medical procedures, and often results in unexpected health issues for the patients. Therefore, in the present paper, we attempt to design a robust feedback controller for an analgesia infusion pump. The plant consists of the patient´s body connected to an infusion pump actuator. A μ-synthesis-based method is employed in order to design a robust controller to regulate the amount of drug injected into the patient´s body, while maintaining the heart rate and blood oxygenation of the patient at a safe level. The controller is designed such that it remains robust to all uncertainties in the patient model that emerge as a result of diversity in the human population. We consider noisy measurements of vital signs in order to show the improvements and reliability of the closed-loop system under practical conditions. Promising results are obtained and discussed at the end of the paper.