title: Anticonvulsant effect of xenon on neonatal asphyxial seizures.
abstract: Xenon, a monoatomic gas with very high tissue solubility, is a non-competitive inhibitor of N-methyl-D-aspartate (NMDA) glutamate receptor, has antiapoptotic effects and is neuroprotective following hypoxic ischaemic injury in animals. Xenon may be expected to have anticonvulsant effects through glutamate receptor blockade, but this has not previously been demonstrated clinically. We examined seizure activity on the real time and amplitude integrated EEG records of 14 full-term infants with perinatal asphyxial encephalopathy treated within 12 h of birth with 30% inhaled xenon for 24 h combined with 72 h of moderate systemic hypothermia. Seizures were identified on 5 of 14 infants. Seizures stopped during xenon therapy but recurred within a few minutes of withdrawing xenon and stopped again after xenon was restarted. Our data show that subanaesthetic levels of xenon may have an anticonvulsant effect. Inhaled xenon may be a valuable new therapy in this hard-to-treat population.
authors.affiliation: Centre for the Developing Brain, King's College London, UK. d.azzopardi@imperial.ac.uk
authors.forename: Denis
authors.initials: D
authors.lastname: Azzopardi
authors.forename: Nicola J
authors.initials: NJ
authors.lastname: Robertson
authors.forename: Andrew
authors.initials: A
authors.lastname: Kapetanakis
authors.forename: James
authors.initials: J
authors.lastname: Griffiths
authors.forename: Janet M
authors.initials: JM
authors.lastname: Rennie
authors.forename: Sean R
authors.initials: SR
authors.lastname: Mathieson
authors.forename: A David
authors.initials: AD
authors.lastname: Edwards
mesh_terms: D018685:Anesthetics, Inhalation / Q000627:therapeutic use; D000927:Anticonvulsants / Q000627:therapeutic use*; D001238:Asphyxia Neonatorum / Q000150:complications*; D001921:Brain / Q000187:drug effects*; D004569:Electroencephalography / Q000187:drug effects; D005260:Female; D006801:Humans; D007036:Hypothermia, Induced / Q000379:methods; D007231:Infant, Newborn; D008297:Male; D018696:Neuroprotective Agents / Q000627:therapeutic use*; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors*; D012640:Seizures / Q000188:drug therapy* / Q000209:etiology; D014978:Xenon / Q000008:administration & dosage*
chemical_list: D018685:Anesthetics, Inhalation; D000927:Anticonvulsants; D018696:Neuroprotective Agents; D016194:Receptors, N-Methyl-D-Aspartate; D014978:Xenon
keywords: Neonatology; Neurodevelopment; Neurodisability; Neurology; Neuropathology