title: Mechanical reperfusion with leucocyte-filtered blood does not prevent injury following global cerebral ischaemia.
abstract: Prolonged global cerebral ischaemia leads to irreversible injury, often with lethal outcome. Brain injuries are partly caused by the uncontrolled reperfusion that occurs once the circulation is re-established. Recent animal experiments suggest that controlled reperfusion following lengthy ischaemia might prevent severe brain injury. This study aimed at further exploring cerebral alterations and outcome following prolonged global cerebral ischaemia and mechanically manipulated reperfusion.
  
  
  
  Three groups of pigs were included; one sham operated ( n  = 3) and two that underwent 30-min global cerebral ischaemia. All vessels that supply the brain were isolated intrathoracically, after which they were occluded for 30 min in the ischaemic groups. In one of the ischaemic groups uncontrolled reperfusion was applied (URep, n  = 6), i.e. normal circulation was restored 30 min after arrested cerebral circulation. The second ischaemic group received mechanical reperfusion (MRep, n  = 6) with leucocyte-filtered blood at constant flow and pressure for 20 min using extracorporeal circulation following the 30-min ischaemia, after which normal blood flow resumed. All animals were monitored for 3 h after start of uncontrolled reperfusion. Haemodynamic parameters, arterial and sagittal sinus blood gases, cerebral oxygen extraction rates and intraparenchymal biomarkers using microdialysis were measured. Brain histology was performed post-mortem.
  
  
  
  Global brain ischaemia led to the same extent of severe morphological changes at the level of light microscopy in the two ischaemic experimental groups, regardless of reperfusion protocol. Furthermore, no significant differences were found between the URep and MRep groups regarding cerebral blood gases or microdialysis biomarkers.
  
  
  
  Mechanical reperfusion following the current protocol does not modify brain alterations caused by 30 min of arrested cerebral circulation.
authors.affiliation: Department of Cardiothoracic Surgery and Anesthesia, Uppsala University Hospital, Uppsala, Sweden.|Section of Thoracic Surgery, Department of Surgical Sciences, Uppsala University, Uppsala, Sweden.
authors.forename: Rickard P F
authors.initials: RPF
authors.lastname: Lindblom
authors.affiliation: Department of Cardiothoracic Surgery and Anesthesia, Uppsala University Hospital, Uppsala, Sweden.|Section of Anesthesiology and Intensive Care, Department of Surgical Sciences, Uppsala University, Uppsala, Sweden.
authors.forename: Thomas
authors.initials: T
authors.lastname: Tovedal
authors.affiliation: Department of Cardiothoracic Surgery and Anesthesia, Uppsala University Hospital, Uppsala, Sweden.
authors.forename: Bo
authors.initials: B
authors.lastname: Norlin
authors.affiliation: Section of Neurosurgery, Department of Neuroscience, Uppsala University, Uppsala, Sweden.
authors.forename: Lars
authors.initials: L
authors.lastname: Hillered
authors.affiliation: Department of Pathology, Uppsala University Hospital, Uppsala, Sweden.
authors.forename: Svetlana N
authors.initials: SN
authors.lastname: Popova
authors.affiliation: Department of Pathology, Uppsala University Hospital, Uppsala, Sweden.|Section of Genetics and Pathology, Department of Immunology, Uppsala University, Uppsala, Sweden.
authors.forename: Irina
authors.initials: I
authors.lastname: Alafuzoff
authors.affiliation: Department of Cardiothoracic Surgery and Anesthesia, Uppsala University Hospital, Uppsala, Sweden.|Section of Thoracic Surgery, Department of Surgical Sciences, Uppsala University, Uppsala, Sweden.
authors.forename: Stefan
authors.initials: S
authors.lastname: Thelin
mesh_terms: D000818:Animals; D001921:Brain / Q000473:pathology; D002545:Brain Ischemia / Q000150:complications* / Q000473:pathology / Q000503:physiopathology; D002245:Carbon Dioxide / Q000097:blood; D002560:Cerebrovascular Circulation / Q000502:physiology; D004195:Disease Models, Animal; D005374:Filtration / Q000379:methods; D006439:Hemodynamics / Q000502:physiology; D047589:Leukocyte Reduction Procedures / Q000379:methods*; D008297:Male; D010100:Oxygen / Q000097:blood; D010313:Partial Pressure; D015424:Reperfusion / Q000379:methods*; D015427:Reperfusion Injury / Q000209:etiology / Q000473:pathology / Q000503:physiopathology / Q000517:prevention & control*; D034421:Sus scrofa
chemical_list: D002245:Carbon Dioxide; D010100:Oxygen
keywords: Cerebral ischaemia; Extracorporeal circulation; Leucocyte filter; Reperfusion