title: Amplitude-integrated electroencephalography and brain injury in infants undergoing Norwood-type operations.
abstract: BACKGROUND
  Perioperative brain injury is common in infants undergoing cardiac surgery. Amplitude-integrated electroencephalography (aEEG) provides real-time neurologic monitoring and can identify seizures and abnormalities of background cerebral activity. We aimed to determine the incidence of perioperative electrical seizures, and to establish the background pattern of aEEG, in neonates undergoing Norwood-type palliations for complex congenital heart disease in relation to outcome at 2 years.
  
  
  METHODS
  Thirty-nine full-term neonates undergoing Norwood-type operations underwent aEEG monitoring before and during surgery and for 72 hours postoperatively. The perfusion strategy included full-flow moderately hypothermic cardiopulmonary bypass with antegrade cerebral perfusion. Amplitude-integrated electroencephalography tracings were reviewed for seizure activity and background pattern. Survivors underwent neurodevelopmental outcome assessment using the Bayley Scales of Infant Development (3rd edition) at 2 years of age.
  
  
  RESULTS
  Thirteen (33%) infants had electrical seizures, including 9 with intraoperative seizures and 7 with postoperative seizures. Seizures were associated with significantly increased mortality, but not with neurodevelopmental impairment in survivors. Delay in recovery of the aEEG background beyond 48 hours was also associated with increased mortality and worse motor development.
  
  
  CONCLUSIONS
  Perioperative seizures were common in this cohort. Intraoperative seizures predominantly affected the left hemisphere during antegrade cerebral perfusion. Delayed recovery in aEEG background was associated with increased risk of early mortality and worse motor development. Ongoing monitoring is essential to determine the longer-term significance of these findings.
authors.affiliation: Department of Neonatal Medicine, The Royal Children's Hospital, Murdoch Children's Research Institute, University of Melbourne, Melbourne, Australia. julia.gunn@rch.org.au
authors.forename: Julia K
authors.initials: JK
authors.lastname: Gunn
authors.forename: John
authors.initials: J
authors.lastname: Beca
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Penny
authors.forename: Stephen B
authors.initials: SB
authors.lastname: Horton
authors.forename: Yves A
authors.initials: YA
authors.lastname: d'Udekem
authors.forename: Christian P
authors.initials: CP
authors.lastname: Brizard
authors.forename: Kirsten
authors.initials: K
authors.lastname: Finucane
authors.forename: Monika
authors.initials: M
authors.lastname: Olischar
authors.forename: Rodney W
authors.initials: RW
authors.lastname: Hunt
authors.forename: Lara S
authors.initials: LS
authors.lastname: Shekerdemian
mesh_terms: D004569:Electroencephalography / Q000379:methods*; D005260:Female; D006330:Heart Defects, Congenital / Q000150:complications / Q000601:surgery*; D006801:Humans; D002534:Hypoxia, Brain / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D007231:Infant, Newborn; D008297:Male; D008991:Monitoring, Physiologic; D058327:Norwood Procedures / Q000009:adverse effects*; D059035:Perioperative Period; D011379:Prognosis; D015203:Reproducibility of Results