Speaker
Description
Background: Several PK/PD models are used for propofol delivery via target-controlled infusion (TCI). The Schnider PK model \cite{schnider1998influence} was developed in younger healthy volunteers. The Eleveld PK/PD model \cite{eleveld2018pharmacokinetic} is a newer general-purpose model for children, elderly, and obese patients. The models differ in effect-site equilibrium rates, with Schnider assuming higher values ($k_{e0}=$ 0.456 vs 0.146/min).
Methods: We compared effects of these models on brain oscillatory activity as measured by frontal electroencephalogram (EEG) during anesthesia induction. We calculated EEG power spectra over time (=from first propofol administration to incision, time normalized to 100\%) using Schnider (n=36) and Eleveld (n=36) models. Differences were statistically tested using 10k-bootstrapped AUROC values with 95% confidence intervals as a measure of effect size \cite{hentschke2011computation}.
Results: Although age, BMI, and effect-site concentration at loss of responsiveness did not differ significantly between groups, the Eleveld group showed significant decreases in beta and low-gamma frequency bands. The decrease was pronounced in the first half of induction with accompanying increases in alpha frequency band.
Conclusion: Anesthesia induction with Schnider and Eleveld PK/PD models may lead to different dynamics at the effect site as measured by the EEG, although future investigation should consider continuous CeP values.
Bibliography
@article{schnider1998influence,
title={The influence of method of administration and covariates on the pharmacokinetics of propofol in adult volunteers},
author={Schnider, Thomas W and Minto, Charles F and Cambus, PL and Andresen, Corina and Goodale, David B and Shafer, Steven L and Youngs, Elizabeth J},
journal={Anesthesiology-Philadelphia then Hagerstown-},
volume={88},
pages={1170--1182},
year={1998},
publisher={JB LIPPINCOTT CO}
}
@article{eleveld2018pharmacokinetic,
title={Pharmacokinetic--pharmacodynamic model for propofol for broad application in anaesthesia and sedation},
author={Eleveld, Douglas J and Colin, Pieter and Absalom, Anthony R and Struys, Michael MRF},
journal={British journal of anaesthesia},
volume={120},
number={5},
pages={942--959},
year={2018},
publisher={Elsevier}
}
@article{hentschke2011computation,
title={Computation of measures of effect size for neuroscience data sets},
author={Hentschke, Harald and St{\"u}ttgen, Maik C},
journal={European Journal of Neuroscience},
volume={34},
number={12},
pages={1887--1894},
year={2011},
publisher={Wiley Online Library}
}
