Semi-adaptive feedback control of opioid infusion

This paper presents a semi-adaptive approach to closed-loop control of opioid infusion. The rationale underlying this approach is to design a controller that can adapt model parameters with a large impact on the model's fidelity and fix the remaining parameters at their nominal values. A low-order model representing opioid dose-response relationship is derived via system identification and parametric sensitivity analysis. Based on the model thus derived, a model reference adaptive controller and a composite adaptive controller are designed, whose performance is compared with non-adaptive control. In-silico simulation results on closed-loop remifentanil control for respiratory rate depression as an example suggest that both controllers can outperform non-adaptive control.