title: Effect of cerebral perfusion pressure augmentation with dopamine and norepinephrine on global and focal brain oxygenation after traumatic brain injury.
abstract: OBJECTIVE
  To compare the effects of a cerebral perfusion pressure (CPP) intervention achieved with dopamine and norepinephrine after severe head injury.
  
  
  METHODS
  Prospective, controlled, trial.
  
  
  METHODS
  Neurosciences critical care unit.
  
  
  METHODS
  Eleven patients with a head injury, requiring dopamine or norepinephrine infusions to support CPP.
  
  
  METHODS
  Cerebral tissue gas measurements were recorded using a multimodal sensor, and regional chemistry was assessed using microdialysis. Patients received in, randomised order, either dopamine or norepinephrine to achieve and maintain a CPP of 65 mmHg, and then, following a 30-min period of stable haemodynamics, a CPP of 85 mmHg. Data were then acquired using the second agent. Haemodynamic measurements and measurements of cerebral physiology were made during each period.
  
  
  RESULTS
  The CPP augmentation with norepinephrine, but not with dopamine, resulted in a significant reduction in arterial-venous oxygen difference (37+/-11 vs 33+/-12 ml/l) and a significant increase in brain tissue oxygen (2.6+/-1.1 vs 3.0+/-1.1 kPa). The CPP intervention did not significantly affect intracranial pressure. There were no significant differences between norepinephrine and dopamine on cerebral oxygenation or metabolism either at baseline or following a CPP intervention; however, the response to a CPP intervention with dopamine seemed to be more variable than the response achieved with norepinephrine.
  
  
  CONCLUSIONS
  If CPP is to be raised to a level higher than 65-70 mmHg, then it is important to recognise that the response to the intervention may be unpredictable and that the vasoactive agent used may be of importance.
authors.affiliation: Department of Anaesthetics, University of Cambridge, Addenbrooke's Hospital, Box 93, Cambridge CB2 2QQ, UK. ajj29@cam.ac.uk
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Johnston
authors.forename: Luzius A
authors.initials: LA
authors.lastname: Steiner
authors.forename: Doris A
authors.initials: DA
authors.lastname: Chatfield
authors.forename: Jonathan P
authors.initials: JP
authors.lastname: Coles
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Hutchinson
authors.forename: Pippa G
authors.initials: PG
authors.lastname: Al-Rawi
authors.forename: David K
authors.initials: DK
authors.lastname: Menon
authors.forename: Arun K
authors.initials: AK
authors.lastname: Gupta
mesh_terms: D000328:Adult; D001930:Brain Injuries / Q000188:drug therapy*; D002316:Cardiotonic Agents / Q000627:therapeutic use*; D003399:Craniotomy; D018592:Cross-Over Studies; D004298:Dopamine / Q000627:therapeutic use*; D005260:Female; D015600:Glasgow Coma Scale; D006801:Humans; D007362:Intensive Care Units; D007427:Intracranial Pressure / Q000187:drug effects*; D008297:Male; D017551:Microdialysis; D008875:Middle Aged; D009638:Norepinephrine / Q000627:therapeutic use*; D013566:Sympathomimetics / Q000627:therapeutic use*
chemical_list: D002316:Cardiotonic Agents; D013566:Sympathomimetics; D004298:Dopamine; D009638:Norepinephrine