title: Incidence of epileptiform EEG activity in children during mask induction of anaesthesia with brief administration of 8% sevoflurane.
abstract: BACKGROUND
  A high incidence of epileptiform activity in the electroencephalogram (EEG) was reported in children undergoing mask induction of anaesthesia with administration of high doses of sevoflurane for 5 minutes and longer. This study was performed to investigate whether reducing the time of exposure to a high inhaled sevoflurane concentration would affect the incidence of epileptiform EEG activity. It was hypothesized that no epileptiform activity would occur, when the inhaled sevoflurane concentration would be reduced from 8% to 4% immediately after the loss of consciousness.
  
  
  RESULTS
  70 children (age 7-96 months, ASA I-II, premedication with midazolam) were anaesthetized with 8% sevoflurane in 100% oxygen via face mask. Immediately after loss of consciousness, the sevoflurane concentration was reduced to 4%. EEGs were recorded continuously and were later analyzed visually with regard to epileptiform EEG patterns. Sevoflurane at a concentration of 8% was given for 1.2 ± 0.4 min (mean ± SD). In 14 children (20%) epileptiform EEG patterns without motor manifestations were observed (delta with spikes (DSP), rhythmic polyspikes (PSR), epileptiform discharges (PED) in 10, 10, 4 children (14%, 14%, 6%)). 38 children (54%) had slow, rhythmic delta waves with high amplitudes (DS) appearing on average before DSP.
  
  
  CONCLUSIONS
  The hypothesis that no epileptiform potentials would occur during induction of anaesthesia with a reduction of the inspired sevoflurane concentration from 8% to 4% directly after LOC was not proved. Even if 8% sevoflurane is administered only briefly for induction of anaesthesia, epileptiform EEG activity may be observed in children despite premedication with midazolam.
authors: Department of Anaesthesiology and Intensive Care Medicine, Hannover Medical School, Hannover, Germany. ab.schultz@t-online.de
authors: Barbara
authors: B
authors: Schultz
authors: Christian
authors: C
authors: Otto
authors: Arthur
authors: A
authors: Schultz
authors: Wilhelm Alexander
authors: WA
authors: Osthaus
authors: Terence
authors: T
authors: Krauss
authors: Thorben
authors: T
authors: Dieck
authors: Björn
authors: B
authors: Sander
authors: Niels
authors: N
authors: Rahe-Meyer
authors: Konstantinos
authors: K
authors: Raymondos
mesh_terms: D018685:Anesthetics, Inhalation / Q000008:administration & dosage / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D004569:Electroencephalography; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D008738:Methyl Ethers / Q000008:administration & dosage / Q000627:therapeutic use*; D008874:Midazolam / Q000494:pharmacology; D011446:Prospective Studies; D000077149:Sevoflurane
chemical_list: D018685:Anesthetics, Inhalation; D008738:Methyl Ethers; D000077149:Sevoflurane; D008874:Midazolam