P 10. Perioperative EEG Signatures in newborn and infants 0 to 12 months

Introduction. EEG based monitoring systems are routinely used for guidance of depth of anesthesia. They have been developed for adult patients however, these monitors have not been validated for children nor for infants [1–5]. Given the toxicity of anesthetics and the lack of possibilities to surveil the level of anesthesia in infants demands for further progress in EEG based monitoring of the developing brain. Method. In a retrospective study frontal peri- and intraoperative EEGs (Narcotrend Monitor) were recorded in 115 infants aged. To analyze EEG dynamics over intraoperative time-points additionally in 20 EEG recordings event markers were added (Baseline EEG, loss of consciousness (LOC), intraoperative maintenance of anesthesia (OP), Extubation). Data are presented as mean with standard deviation. Results. Newborns show a mean relative δ-power at 80% in intraoperative EEG compared to infants (10-12 months) showing 47,5%. EEG dynamics in newborns from baseline (relative δ-power of 88%) to the intraoperative situation (80.5%) are discreet. The total power is constant from baseline to OP and shows a reduction at the time of extubation. In contrast infants >6-months have a strong reduction of relative δ-power from baseline to the intraoperative situation, which corresponds to an increase of faster frequencies. Discussion. Age-dependent EEG changes can be demonstrated in infants younger than one year under general anesthesia with sevoflurane which questions our today's monitoring systems in pediatric anesthesia. To improve EEG guided anesthesia in the future more studies are needed to advance the accuracy of EEG Monitors for pediatric anesthesia. References 1. Cornelissen, L., et al., Age-dependent electroencephalogram (EEG) patterns during sevoflurane general anesthesia in infants. Elife, 2015. 4: p. e06513. 2. Akeju, O., et al., Age-dependency of sevoflurane-induced electroencephalogram dynamics in children. Br J Anaesth, 2015. 115 Suppl 1(Suppl 1): p. i66-i76. 3. Cornelissen, L., et al., Electroencephalographic markers of brain development during sevoflurane anaesthesia in children up to 3 years old. Br J Anaesth, 2018. 120(6): p. 1274-1286. 4. de Heer, I.J., S.J.M. Bouman, and F. Weber, Electroencephalographic (EEG) density spectral array monitoring in children during sevoflurane anaesthesia: a prospective observational study. Anaesthesia, 2019. 74(1): p. 45-50. 5. Purdon, P.L., et al., Electroencephalogram signatures of loss and recovery of consciousness from propofol. Proc Natl Acad Sci U S A, 2013. 110(12): p. E1142-51. Fig. 1. Fig. 2.