title: Direct cerebral perfusion and cooling in experimental cardiac arrest.
abstract: Cerebral protection is a key priority during cardiac arrest (CA). However, current approaches are suboptimal.
  
  
  
  To test whether direct perfusion and cooling of the anterior cerebral circulation by means of cerebral vessel cannulation and extracorporeal membrane oxygenation (ECMO) increases cerebral oxygenation and induces cerebral hypothermia during CA.
  
  
  
  We performed proof-of-concept animal experiments in sheep. We cannulated the carotid artery (for antegrade perfusion) or the jugular vein (for retrograde perfusion) for direct perfusion and cooling, and the jugular vein on the opposite side for drainage. We connected these cannulae to an ECMO circuit. We induced CA and, after 10 minutes, and during open-chest cardiac massage, we provided ECMO-based perfusion and cooling. We measured cerebral tissue oxygen saturation (SctO2) by near infrared spectroscopy (NIRS) and cerebral temperature by means of invasively inserted tissue temperature probes.
  
  
  
  In the antegrade perfusion experiments (n = 2), CA markedly decreased the SctO2to below 40% over 10 minutes, despite open-chest cardiac massage. ECMO-based cerebral perfusion and cooling increased SctO2levels to 60% and lowered cerebral temperature to 25°C within about 3 minutes. With retrograde perfusion (n = 2), ECMObased cerebral perfusion and cooling was less effective; ECMO increased SctO2levels slowly and to a much lesser extent and similarly decreased cerebral temperature slowly and to a lesser extent.
  
  
  
  During experimental CA, cerebral perfusion and cooling are possible by means of an ECMO circuit connected to the anterior cerebral circulation. Antegrade perfusion appears to be superior. Further investigations of the antegrade perfusion technique appear justified.
authors.affiliation: School of Medicine, University of Melbourne, Melbourne, VIC, Australia. rinaldo.bellomo@austin.org.au.
authors.forename: Rinaldo
authors.initials: R
authors.lastname: Bellomo
authors.affiliation: Department of Perfusion Services, Austin Hospital, Melbourne, VIC, Australia.
authors.forename: Bruno
authors.initials: B
authors.lastname: Marino
authors.affiliation: Department of Perfusion Services, Austin Hospital, Melbourne, VIC, Australia.
authors.forename: Peter
authors.initials: P
authors.lastname: Angelopoulos
authors.affiliation: Department of Perfusion Services, Austin Hospital, Melbourne, VIC, Australia.
authors.forename: Scott
authors.initials: S
authors.lastname: Carson
authors.affiliation: Department of Intensive Care, Austin Hospital, Melbourne, VIC, Australia.
authors.forename: Glenn
authors.initials: G
authors.lastname: Eastwood
authors.affiliation: Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, VIC, Australia.
authors.forename: Junko
authors.initials: J
authors.lastname: Kosaka
authors.affiliation: Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, VIC, Australia.
authors.forename: Naoya
authors.initials: N
authors.lastname: Iguchi
authors.affiliation: Department of Intensive Care, Austin Hospital, Melbourne, VIC, Australia.
authors.forename: Andrew
authors.initials: A
authors.lastname: Hilton
authors.affiliation: Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, VIC, Australia.
authors.forename: Clive
authors.initials: C
authors.lastname: May
mesh_terms: D000818:Animals; D002560:Cerebrovascular Circulation; D015199:Extracorporeal Membrane Oxygenation; D006323:Heart Arrest / Q000628:therapy*; D007036:Hypothermia, Induced; D015424:Reperfusion; D012756:Sheep