title: The influence of deep hypothermic global brain ischemia on EEG in a new rat model.
abstract: OBJECTIVE
  Neurological complications following deep hypothermic circulatory arrest (DHCA) occur between t 4% ≈ 25%. However, the cerebral injury mechanisms are still not well understood due to a lack of a practical and simple animal model. We aimed to establish a rodent deep hypothermic global brain ischemia (DHGBI) model, which can be used to elucidate these mechanisms in future studies.
  
  
  METHODS
  30 Sprague-Dawley rats were divided randomly into three groups: the carotid occlusion DHGBI group, the internal carotid shunt DHGBI group, and the sham operation group. We validated the model in terms of electroencephalogram (EEG) and regional cerebral blood flow (rCBF). All rats were sacrificed for analysis of brain moisture capacity after 24 hours.
  
  
  RESULTS
  In the internal carotid shunt DHGBI group the EEG activity was suppressed to "flat-line" and the relative power of the α and θ frequency bands was decreased (p < 0.05). However, in the carotid occlusion DHGBI group we only observed the relative power of the α frequency band depressed (p < 0.05). The rCBF was significantly decreased in all groups. In the internal carotid shunt DHGBI group the rCBF was significantly reduced to 4.27 ± 2.75%, and was lower than the other two groups (p < 0.05). The result of brain moisture capacity was consistent with the EEG and rCBF observations.
  
  
  CONCLUSIONS
  The current study presents a novel cerebral recovery model of DHCA in the rat. This experimental model may be suitable to further elucidate the mechanisms associated with adverse cerebral outcomes after DHCA and to investigate potential neuroprotective strategies.
authors.affiliation: Jiangsu Province Hospital, First Affiliated Hospital with Nanjing Medical University, Department of Cardiothoracic Surgery, Nanjing, China.
authors.forename: Qun
authors.initials: Q
authors.lastname: Gu
authors.forename: Haitao
authors.initials: H
authors.lastname: Gu
authors.forename: Xiaohu
authors.initials: X
authors.lastname: Lu
authors.forename: Fengxia
authors.initials: F
authors.lastname: Lu
authors.forename: Yongfeng
authors.initials: Y
authors.lastname: Shao
authors.forename: Shijiang
authors.initials: S
authors.lastname: Zhang
mesh_terms: D000818:Animals; D002545:Brain Ischemia / Q000175:diagnosis* / Q000209:etiology* / Q000401:mortality; D002560:Cerebrovascular Circulation / Q000502:physiology*; D050792:Circulatory Arrest, Deep Hypothermia Induced / Q000009:adverse effects*; D004195:Disease Models, Animal; D004569:Electroencephalography; D006439:Hemodynamics / Q000502:physiology; D008297:Male; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D012016:Reference Values; D015996:Survival Rate