title: Systematic characterization of amplitude-integrated EEG signals for monitoring the preterm brain.
abstract: BACKGROUND
  In preterm infants, the amplitude-integrated electroencephalogram (aEEG) is not established in clinical routine. The aim of this study was to derive normative data on aEEG parameters by means of longitudinal characterization and to evaluate the impact of gestational age (GA), postnatal age (PNA), postmenstrual age, sedation, and patent ductus arteriosus (PDA).
  
  
  METHODS
  Recordings from 61 infants with GA 28-31 weeks were obtained during the first 72 h, then weekly until the age of 4 wk. Infants were divided into three groups: (i) no sedation, no PDA, (ii) sedation, no PDA, and (iii) sedation, PDA. Assessed parameters included background activity, cycling, amplitude, and log ratio of the maximum/minimum amplitude.
  
  
  RESULTS
  GA and PNA had a significant impact within 72 h. Sedation modified aEEG, and presence of PDA was associated with reduced aEEG scores within 72 h. The log ratio of the amplitude correlated with GA but was unaffected by sedation and PDA.
  
  
  CONCLUSIONS
  Evaluation of electrocortical background activity within the first postnatal hours and longitudinally over days and weeks is important to better understand the postnatal factors impacting cerebral function in preterm infants. There is a need to agree on definitions and a standardized reporting system in order to permit comparisons between studies and establish aEEG as a method for routine monitoring of preterm infants.
authors.affiliation: Department of Pediatrics II, Medical University of Innsbruck, Innsbruck, Austria. Elke.Griesmaier@i-med.ac.at
authors.forename: Elke
authors.initials: E
authors.lastname: Griesmaier
authors.forename: David Pierre
authors.initials: DP
authors.lastname: Enot
authors.forename: Miriam
authors.initials: M
authors.lastname: Bachmann
authors.forename: Vera
authors.initials: V
authors.lastname: Neubauer
authors.forename: Lena
authors.initials: L
authors.lastname: Hellström-Westas
authors.forename: Ursula
authors.initials: U
authors.lastname: Kiechl-Kohlendorfer
authors.forename: Matthias
authors.initials: M
authors.lastname: Keller
mesh_terms: D000367:Age Factors; D001921:Brain / Q000187:drug effects / Q000503:physiopathology*; D001930:Brain Injuries / Q000175:diagnosis* / Q000503:physiopathology; D058256:Brain Waves / Q000187:drug effects; D004374:Ductus Arteriosus, Patent / Q000503:physiopathology; D004569:Electroencephalography / Q000592:standards; D005260:Female; D005865:Gestational Age; D006801:Humans; D006993:Hypnotics and Sedatives / Q000627:therapeutic use; D007231:Infant, Newborn; D007234:Infant, Premature; D016018:Least-Squares Analysis; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D008991:Monitoring, Physiologic / Q000379:methods* / Q000592:standards; D016017:Odds Ratio; D011237:Predictive Value of Tests; D012015:Reference Standards; D013997:Time Factors
chemical_list: D006993:Hypnotics and Sedatives