Beschreibung:
<jats:title>Summary</jats:title><jats:p><jats:bold>Background: </jats:bold> The Narcotrend Index (NI) of anesthetic depth is potentially a pharmacodynamic measure of the effects of sevoflurane on the brain.</jats:p><jats:p><jats:bold>Methods: </jats:bold> In this prospective observational study of 30 pediatric surgical patients (1–11 years), we investigated the correlation between nonsteady‐state endtidal sevoflurane (eT<jats:sub>Sevo</jats:sub>), NI, mean arterial pressure (MAP), and heart rate (HR). The performance of the Narcotrend for differentiation between consciousness and unconsciousness was evaluated using prediction probability (<jats:italic>P</jats:italic><jats:sub>K</jats:sub>).</jats:p><jats:p><jats:bold>Results: </jats:bold> Spearman correlation analysis showed significant correlations (<jats:italic>P</jats:italic> < 0.01) between eT<jats:sub>Sevo</jats:sub> and NI (<jats:italic>r</jats:italic> = −0.85) and MAP (<jats:italic>r</jats:italic> = −0.43). <jats:italic>P</jats:italic><jats:sub>K</jats:sub>‐values for differentiation between consciousness and unconsciousness were 1.0 for NI and <0.85 for MAP and HR. During the surgical procedure, NI‐values showed a constant rise with each 0.5% step of lowering eT<jats:sub>Sevo</jats:sub> (<jats:italic>P</jats:italic> < 0.03), whereas MAP remained unaltered and HR showed a constant decline (<jats:italic>P</jats:italic> < 0.03), except between 1.5 and 1%.</jats:p><jats:p><jats:bold>Conclusions: </jats:bold> In children, nonsteady‐state eT<jats:sub>Sevo</jats:sub> concentrations are more closely related with NI than with MAP or HR. In this study, only NI reliably differentiated consciousness from unconsciousness.</jats:p>