Clinical Comparison Between Two Propofol TCI Models(Eleveld and Schnider) for General Anaesthesia After Premedication With Midazolam

During recent years Eleveld and colleagues ideated a new propofol pharmacokinetic/pharmacodynamic (PK/PD) model for total intravenous anaesthesia with target controlled infusion (TIVA-TCI) pumps that has been proposed to have slightly better predictive performance for measured propofol plasma concentrations compared with those of the Marsh and Schnider models, and suitable for children, adults, older subjects, and obese adults, being considered as a "General purpose" model.

However, no trials have compared the Eleveld to the Schnidermodel after a premedication with Midazolam bolus (0.03 mg/kg) from a clinical point of view; so, this study aimed toevaluate midazolam effect on the estimated effector site concentration of the two models (CePE and CePS, respectively) at loss of responsiveness (LoR), during anaesthesia maintenance (Bispectral Index [BIS] 40-60) and return of responsiveness (RoR). The study also compared the incidence of deepening or superficializing anaesthesia (defined respectively as lowering or increasing in out-of-target BIS after initial CeP detection), as well as unwanted anaesthesia events: burst suppression (BSupp, identified as a burst suppression ratio [BSR] >0) and unwanted spontaneous responsiveness.