title: Relationship between early changes in cerebral blood volume and electrocortical activity after hypoxic-ischemic insult in newborn piglets.
abstract: BACKGROUND
  Early changes in cerebral hemodynamics and depressed electrocortical activity have been reported after a hypoxic-ischemic (HI) insult. However, the relationship between these two parameters is unclear. This study aimed to examine the relationship between changes in cerebral blood volume (CBV) and cerebral Hb oxygen saturation (ScO2) after a HI insult and the low amplitude-integrated electroencephalography (aEEG) duration concomitantly observed.
  
  
  METHODS
  Sixteen newborn piglets obtained within 24h of birth were used (n=3 controls). Thirteen piglets were subjected to a HI insult of 20-min low-amplitude aEEG (<5 μV, LAEEG), after which a low mean arterial blood pressure (<70% of baseline) was maintained for 10 min. We measured changes in CBV and ScO2 using near-infrared time-resolved spectroscopy (TRS) and cerebral electrocortical activities using aEEG until 6h after the insult.
  
  
  RESULTS
  A positive correlation was observed between the LAEEG duration and CBV increase, but not ScO2, after the insult.
  
  
  CONCLUSIONS
  These results suggest that a larger increase in CBV reflected a more severe failure in cerebral circulation to maintain cell membrane action potentials, which induced a more extended recovery period of electrocortical activity after the insult. We conclude that an early increase in CBV and longer LAEEG indicate severe brain injury.
authors.affiliation: Department of Pediatrics, Faculty of Medicine, Kagawa University, Kagawa, Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Nakamura
authors.affiliation: Maternal Perinatal Center, Faculty of Medicine, Kagawa University, Kagawa, Japan. Electronic address: kusaka@medkagawa-u.ac.jp.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kusaka
authors.affiliation: Maternal Perinatal Center, Faculty of Medicine, Kagawa University, Kagawa, Japan.
authors.forename: Kosuke
authors.initials: K
authors.lastname: Koyano
authors.affiliation: Department of Anatomy and Neurobiology, Faculty of Medicine, Kagawa University, Kagawa, Japan.
authors.forename: Takanori
authors.initials: T
authors.lastname: Miki
authors.affiliation: Department of Pathology and Host Defense, Faculty of Medicine, Kagawa University, Kagawa, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Ueno
authors.affiliation: Department of Pediatrics, Faculty of Medicine, Kagawa University, Kagawa, Japan.
authors.forename: Wataru
authors.initials: W
authors.lastname: Jinnai
authors.affiliation: Maternal Perinatal Center, Faculty of Medicine, Kagawa University, Kagawa, Japan.
authors.forename: Saneyuki
authors.initials: S
authors.lastname: Yasuda
authors.affiliation: Department of Pediatrics, Faculty of Medicine, Kagawa University, Kagawa, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Nakamura
authors.affiliation: Department of Pediatrics, Faculty of Medicine, Kagawa University, Kagawa, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Okada
authors.affiliation: Department of Pediatrics, Faculty of Medicine, Kagawa University, Kagawa, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Isobe
authors.affiliation: Department of Pediatrics, Faculty of Medicine, Kagawa University, Kagawa, Japan.
authors.forename: Susumu
authors.initials: S
authors.lastname: Itoh
mesh_terms: D000818:Animals; D001810:Blood Volume; D002540:Cerebral Cortex / Q000098:blood supply* / Q000503:physiopathology*; D004569:Electroencephalography; D005260:Female; D020925:Hypoxia-Ischemia, Brain / Q000503:physiopathology*; D008297:Male; D010100:Oxygen / Q000378:metabolism; D013552:Swine
chemical_list: D010100:Oxygen
keywords: Cerebral blood volume amplitude-integrated electroencephalography; Electroencephalography; Hypoxia–ischemia; Near-infrared time-resolved spectroscopy