The Incidence Of Epileptiform Discharges And Effects Of Etomidate On Epileptiform Discharges In Children During Mask Induction Of Sevoflurane

Background and objective The epileptiform discharges were frequently confirmed in children during sevoflurane induction since the application of electroencephalography(EEG)monitoring in pediatric anesthesia.According to the description of Vakkuri et al.,the epileptiform discharges can be divided into several types: delta with spikes(DSP),rhythmic polyspikes(PSR),periodic epileptiform discharges(PED),and suppression with spikes(SSP).Many studies have shown that these paradoxical discharges found in children are related to poorer cognitive performance and emergency delirium.Epileptic discharges during induction of anesthesia may indicate impaired brain function in these children,leading to further cognitive or behavioral complications.However,the incidence,risk factors of these epileptiform patterns during sevoflurane anesthesia in children are still under debate.Several studies have shown that sevoflurane-induced EEG seizures are often accompanied by an increased level of serum corticosterone and cortisol,and the EEG seizures caused by this drug can be inhibited by corticosteroid receptor antagonists,which suggesting that cortisol may be involved in the regulation of EEG epileptic discharges.And the inhibiting effect of etomidate on adrenocortical function may cause a decreased level of serum cortisol concentration.Whether this effect can reduce the epileptic discharge caused by sevoflurane by reducing cortisol is still unclear.In addition,other trials have shown that etomidate can increase the frequency of interictal discharges(including spikes and high-frequency oscillations)during the in patients with epilepsy,which suggesting that etomidate may also increase the occurrence of epileptic discharges in children during the induction period of sevoflurane and impact their cognition.The two paradoxical hypotheses suggested that etomidate may influence the occurrence of epileptic EEG waves during sevoflurane induction in children.Hence,the current study aimed to investigate the overall incidence and risk factors of epileptiform discharges in children during sevoflurane induction by meta-analysis,and to investigate whether etomidate affect the occurrence of epileptic EEG patters during sevoflurane induction,and further affecting the occurrence of emergency delirium in children.Methods and results1.Incidence of epileptiform discharges in children during sevoflurane induction: a single rate metaanalysisMethods Pub Med,EMBASE,Cochrane library(central),CNKI,Wanfang database were searched without language restriction.The trials aiming to investigate the effect of sevoflurane on epileptic EEG patters in children was included into the current study.The primary outcome was the overall incidence of epileptiform discharges during sevoflurane induction in children,the additional outcomes were the incidence of DSP,PSR,PED,SSP and risk factors of these epileptic EEG patters.Two researchers independently screened the study and extracted the data.Meta-analysis was performed by using R software.Results Nine trials involving 374 participants were included into the meta-analysis.The overall incidence of epileptiform discharges during sevoflurane mask induction in children was 39.36%.Of which,the incidence of DSP,PSR,PED and SSP were respectively 32.00%,16.21%,10.00%,and 4.59%.Compared with the method of increasing concentration,shorter administration time of high concentration sevoflurane and no addition of nitrous oxide during induction,the occurrence of epileptic discharges was higher when participants were anesthetized by using tidal volume method,longer administration time of high concentration sevoflurane and the addition of nitrous oxide during induction(50.03% VS 1.60%,54.97% VS 20.28%,69.16% VS 40.67%).2.Effects of etomidate on epileptiform discharges in children during mask induction of sevoflurane Methods Forty-eight pediatric patients aged from 2 to 12 years undergoing elective surgeries were randomly divided into group E(etomidate group)or group C(control group).All patients were given midazolam 0.05mg/kg before entering the operating room,electroencephalogram(EEG)was established during this period.Respiratory circuit was prefilled with 8% sevoflurane and oxygen of 6L/min.After entering the operating room,electrocardiogram(ECG),blood pressure,blood oxygen saturation monitoring and EEG monitoring were recorded.After a 3 min of EEG stable period,Sevoflurane mask induction for children was performed.In etomidate group,patients were intravenously given etomidate 0.1mg/kg followed by mask induction of 8% sevoflurane.In the control group,a comparable volume of saline was intravenously given followed by mask induction of 8% sevoflurane.After sevoflurane induction,cisatracurium was given 0.1mg/kg,remifentanil was given 1μg/kg.The laryngeal mask or endotracheal tube were placed after satisfactory muscle relaxation.The primary outcome of this trial was the incidence of epileptiform EEG patterns during sevoflurane anesthesia.The secondary outcome was the occurrence of emergency delirium in children.Results The results of this study showed that a single dose(0.1mg/kg)of etomidate before induction of high concentration(8%)sevoflurane significantly increased the incidence of epileptic discharge during sevoflurane induction in children compared with the control group(87.5% VS 62.5%).P < 0.05).Of which,the incidence of DSP in etomidate group was statistically higher than the control group,but no significant differences between groups were found in the incidence of SSP,PSR and PED.Furthermore,the incidence of emergency delirium and PAED score in etomidate group were higher compared to the control group(37.5% VS 25.0%;8.07±3.08 VS 7.35±3.29),although the difference between groups was not statistically significant(P > 0.05).Conclusion In conclusion,the overall incidence of epileptic EEG patters in children during sevoflurane induction was 39.36%.Different methods of sevoflurane induction,administration time of high concentration sevoflurane and addition of nitrous oxide may affect the occurrence of epileptic discharge.The occurrence of these EEG patters may be increased by a single dose of etomidate before inhalation induction,which may provide a new idea for the investigation of mechanism of sevoflurane-induced epileptic discharges.