Experimental results of an event-based PID control system for propofol and remifentanil coadministration

This paper presents the first experimental results obtained with an event-based PID regulator for closed-loop control of general anesthesia. The control system exploits the bispectral index scale as feedback variable and regulates the coadministration of propofol and remifentanil. The experiments have been conducted on fourteen patients under conditions that are representative of the routine clinical practice. The results obtained show that the performance of the event-based control system is consistent with the standards of care. In particular, a noise-free infusion profile is obtained, which mimics the behavior of the anesthesiologist and reduces the control effort on the infusion pumps. This makes the control system easy to apply and to supervise since its behavior is intuitive for the anesthesiologist. Thus, the proposed solution represent a step forward for the acceptance and diffusion of closed-loop control systems in the routine clinical practice.