title: The effects of stellate ganglion block on the electroencephalogram in rats.
abstract: OBJECTIVE
  It is reported that the sympathetic nervous system may play an important role in the arousal response. The present study evaluated the effect of stellate ganglion block (SGB) on electroencephalogram (EEG) activity in rats.
  
  
  METHODS
  Adult male Sprague-Dawley rats were divided into two groups: SGB (n = 10) or intramuscular (IM, n = 10) injection was performed with 0.2 ml 0.25 % bupivacaine. The spectral edge frequency 95 % (SEF 95 %), median frequency (MF), beta to theta ratio (BTR), and beta to delta ratio (BDR) were estimated 30 min before bupivacaine injection and 15, 20, 25, 30, 45, 55, and 100 min after SGB or IM injection.
  
  
  RESULTS
  Ipsilateral ptosis occurred in all the rats that underwent SGB but did not occur in the IM group. Significant decrease of the 95 % SEF value, MF, BTR, and BDR was observed from 15 to 45 min after SGB compared with those of the IM group, respectively (p < 0.05).
  
  
  CONCLUSIONS
  SGB with 0.2 ml 0.25 % bupivacaine significantly decreased EEG activities in rats. These results suggest that SGB can induce a sedative effect in rats. Further studies are required to investigate the behavioral tests for sedative effects of SGB.
authors.affiliation: Department of Anesthesiology and Pain Medicine, Dongguk University Ilsan Hospital, Goyang, Republic of Korea.
authors.forename: Seunghyun
authors.initials: S
authors.lastname: Jeong
authors.forename: Younghoon
authors.initials: Y
authors.lastname: Jeon
authors.forename: Jinseok
authors.initials: J
authors.lastname: Yeo
authors.forename: Woonyi
authors.initials: W
authors.lastname: Baek
mesh_terms: D000779:Anesthetics, Local / Q000494:pharmacology; D000818:Animals; D004569:Electroencephalography / Q000187:drug effects*; D005730:Ganglionic Blockers / Q000494:pharmacology*; D006339:Heart Rate / Q000187:drug effects; D006993:Hypnotics and Sedatives / Q000494:pharmacology; D008297:Male; D009407:Nerve Block; D051381:Rats; D017207:Rats, Sprague-Dawley; D013233:Stellate Ganglion
chemical_list: D000779:Anesthetics, Local; D005730:Ganglionic Blockers; D006993:Hypnotics and Sedatives