title: Do different anesthesia regimes affect hippocampal apoptosis and neurologic deficits in a rodent cardiac arrest model?
abstract: BACKGROUND
  Different anesthesia regimes are commonly used in experimental models of cardiac arrest, but the effects of various anesthetics on clinical outcome parameters are unknown. We conducted a study in which we subjected rats to cardiac arrest under medetomidine/ketamine or sevoflurane/fentanyl anesthesia.
  
  
  METHODS
  Asystolic cardiac arrest for 8 minutes was induced in 73 rats with a mixture of potassium chloride and esmolol. Daily behavioral and neurological examination included the open field test (OFT), the tape removal test (TRT) and a neurodeficit score (NDS). Animals were randomized for sacrifice on day 2 or day 5 and brains were harvested for histology in the hippocampus cornus ammonis segment CA1. The inflammatory markers IL-6, TNF-α, MCP-1 and MIP-1α were assessed in cerebrospinal fluid (CSF). Proportions of survival were tested with the Fisher's exact test, repeated measurements were assessed with the Friedman's test; the baseline values were tested using Mann-Whitney U test and the difference of results of repeated measures were compared.
  
  
  RESULTS
  In 31 animals that survived beyond 24 hours neither OFT, TRT nor NDS differed between the groups; histology was similar on day 2. On day 5, significantly more apoptosis in the CA1 segment of the hippocampus was found in the sevoflurane/fentanyl group. MCP-1 was higher on day 5 in the sevoflurane/fentanyl group (p = 0.04). All other cyto- and chemokines were below detection threshold.
  
  
  CONCLUSIONS
  In our cardiac arrest model neurological function was not influenced by different anesthetic regimes; in contrast, anesthesia with sevoflurane/fentanyl results in increased CSF inflammation and histologic damage at day 5 post cardiac arrest.
authors.affiliation: Department of Intensive Care Medicine, University Hospital - Inselspital and University of Bern, Bern, Switzerland. stepani.bendel@KUH.fi.|Department of Intensive Care Medicine, Kuopio University Hospital, Kuopio, Finland. stepani.bendel@KUH.fi.
authors.forename: Stepani
authors.initials: S
authors.lastname: Bendel
authors.affiliation: Department of Intensive Care Medicine, University Hospital - Inselspital and University of Bern, Bern, Switzerland. dirk.springe@insel.ch.
authors.forename: Dirk
authors.initials: D
authors.lastname: Springe
authors.affiliation: Department of Intensive Care Medicine, University Hospital - Inselspital and University of Bern, Bern, Switzerland. adrianojop@yahoo.br.
authors.forename: Adriano
authors.initials: A
authors.lastname: Pereira
authors.affiliation: Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Bern, Switzerland. denis.grandgirard@ifik.unibe.ch.
authors.forename: Denis
authors.initials: D
authors.lastname: Grandgirard
authors.affiliation: Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Bern, Switzerland. stephen.leib@ifik.unibe.ch.|Biology Division, Spiez Laboratory, Federal Office for Civil Protection, Spiez, Switzerland. stephen.leib@ifik.unibe.ch.
authors.forename: Stephen L
authors.initials: SL
authors.lastname: Leib
authors.affiliation: Department of Intensive Care Medicine, University Hospital - Inselspital and University of Bern, Bern, Switzerland. alessandroputzu@ymail.com.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Putzu
authors.affiliation: Department of Intensive Care Medicine, University Hospital - Inselspital and University of Bern, Bern, Switzerland. jannisschlickeiser@hotmail.com.
authors.forename: Jannis
authors.initials: J
authors.lastname: Schlickeiser
authors.affiliation: Department of Intensive Care Medicine, University Hospital - Inselspital and University of Bern, Bern, Switzerland. stephan.jakob@insel.ch.
authors.forename: Stephan M
authors.initials: SM
authors.lastname: Jakob
authors.affiliation: Department of Intensive Care Medicine, University Hospital - Inselspital and University of Bern, Bern, Switzerland. jukka.takala@insel.ch.
authors.forename: Jukka
authors.initials: J
authors.lastname: Takala
authors.affiliation: Department of Intensive Care Medicine, University Hospital - Inselspital and University of Bern, Bern, Switzerland. matthias.haenggi@insel.ch.
authors.forename: Matthias
authors.initials: M
authors.lastname: Haenggi
mesh_terms: D000777:Anesthetics / Q000494:pharmacology*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D005283:Fentanyl / Q000494:pharmacology; D006323:Heart Arrest / Q000503:physiopathology*; D006624:Hippocampus / Q000187:drug effects; D007649:Ketamine / Q000494:pharmacology; D008297:Male; D020926:Medetomidine / Q000494:pharmacology; D008738:Methyl Ethers / Q000494:pharmacology; D009422:Nervous System Diseases / Q000517:prevention & control*; D017208:Rats, Wistar; D000077149:Sevoflurane
chemical_list: D000777:Anesthetics; D008738:Methyl Ethers; D000077149:Sevoflurane; D007649:Ketamine; D020926:Medetomidine; D005283:Fentanyl