title: Effects of regional brain injury on the newborn autonomic nervous system.
abstract: OBJECTIVE
  Cerebral mapping of central autonomic nervous system (ANS)(1) function in mature animals and humans lateralizes sympathetic and parasympathetic influence predominantly to the right and left cerebral hemispheres, respectively. Spectral analysis of heart rate variability (HRV)(2) is an established measure of ANS function. We examined whether such lateralization is present in the term newborn.
  
  
  METHODS
  We retrospectively reviewed records of infants >36 weeks of gestation diagnosed with hypoxic ischemic encephalopathy (HIE).(3) We included infants with neonatal EEG and regional injury on brain MRI, which was scored using a schema. We extracted ECG signals from the EEG recording, but excluded periods of electrographic seizure activity to eliminate possible seizure influence on HRV. HRV was evaluated by spectral analysis in the high frequency (HF(4); 0.3-1 Hz) and low frequency (LF(5); 0.05-0.25 Hz) ranges, and the LF/HF ratio was examined to assess sympatho-vagal balance. The relation between the injured brain regions and HRV was studied using multiple linear regression models.
  
  
  RESULTS
  We studied 40 neonates with HIE. Injury to the right cerebral cortex (p=0.009) and right cerebellum (p=0.041) predicted a decreased LF/HF ratio. Injury to the left cerebral cortex (p=0.035) and left cerebellum (p=0.041) was associated with an increased LF/HF ratio. The association between brain injury location and the individual LF or HF spectral powers of brain injury did not reach significance.
  
  
  CONCLUSIONS
  Our data suggest that a functional lateralization for cerebral autonomic influence is established by term gestation.
authors.affiliation: Children's National Health System, Fetal Medicine Institute, Division of Fetal and Transitional Medicine, 111 Michigan Avenue, NW, Washington, DC 20010, USA. Electronic address: nschneeb@childrensnational.org.
authors.forename: Nira
authors.initials: N
authors.lastname: Schneebaum Sender
authors.affiliation: Children's National Health System, Fetal Medicine Institute, Division of Fetal and Transitional Medicine, 111 Michigan Avenue, NW, Washington, DC 20010, USA. Electronic address: rgovinda@childrensnational.org.
authors.forename: Rathinaswamy B
authors.initials: RB
authors.lastname: Govindan
authors.affiliation: Boston Children's Hospital, Department of Surgery, 300 Longwood Avenue, Boston, MA 02115, USA. Electronic address: msulemanji@hmc.psu.edu.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Sulemanji
authors.affiliation: Children's National Health System, Fetal Medicine Institute, Division of Fetal and Transitional Medicine, 111 Michigan Avenue, NW, Washington, DC 20010, USA. Electronic address: talshargabi@gmail.com.
authors.forename: Tareq
authors.initials: T
authors.lastname: Al-Shargabi
authors.affiliation: University of Central Arkansas, Department of Mathematics, 201 Donaghey Avenue, Conway, AR 72035, USA. Electronic address: rblenin@uca.edu.
authors.forename: R B
authors.initials: RB
authors.lastname: Lenin
authors.affiliation: SUNY Upstate Medical University, Golisano Children's Hospital, Department of Pediatric Neurology, 750 East Adams Street, Syracuse, NY 13210, USA. Electronic address: eksiogly@upstate.edu.
authors.forename: Yaman Z
authors.initials: YZ
authors.lastname: Eksioglu
authors.affiliation: Children's National Health System, Fetal Medicine Institute, Division of Fetal and Transitional Medicine, 111 Michigan Avenue, NW, Washington, DC 20010, USA. Electronic address: ADupless@childrensnational.org.
authors.forename: Adre J
authors.initials: AJ
authors.lastname: du Plessis
mesh_terms: D001341:Autonomic Nervous System / Q000503:physiopathology*; D001930:Brain Injuries / Q000503:physiopathology*; D001931:Brain Mapping; D004562:Electrocardiography; D005260:Female; D007839:Functional Laterality; D006339:Heart Rate; D006801:Humans; D020925:Hypoxia-Ischemia, Brain / Q000503:physiopathology*; D007231:Infant, Newborn; D008297:Male; D012189:Retrospective Studies
keywords: Autonomic nervous system; Brain maturation; Heart rate variability