title: The effect of leucocyte-depleting arterial line filters on cerebral microemboli and neuropsychological outcome following coronary artery bypass surgery.
abstract: OBJECTIVE
  A randomised clinical trial sought evidence as to whether leucocyte-depleting (LD) arterial line filters added a further degree of neuroprotection in patients undergoing elective coronary artery bypass graft (CABG) surgery.
  
  
  METHODS
  One hundred and ninety-two patients were randomised to the use of a Pall Leukoguard-6 LD filter or either an Avecor Affinity or Pall Autovent-6 control filter. Cerebral microemboli during surgery were recorded by transcranial Doppler (TCD) monitor over the right middle cerebral artery. Evidence of cerebral impairment was obtained by comparing patients' performance in a neuropsychological (NP) test battery (nine tests) administered 6-8 weeks post-operatively with their pre-operative scores.
  
  
  RESULTS
  The groups proved well balanced in pre-operative variables. During cardiopulmonary bypass (CPB) the median number and range of microemboli was 15 (3-180) in the LD group compared to 67 (5-846) and 55 (2-773) for the Avecor and AV6 groups, respectively (P<0.0001). One hundred and sixty-two patients completed all the NP tests. The LD group showed better post-operative performance in all but one of the nine tests although the difference in a total change score just failed to reach significance (P=0.07 one-tailed t-test).
  
  
  CONCLUSIONS
  LD filtration during CABG reduced the number of cerebral microemboli recorded by TCD and showed a strong trend towards improving NP performance post-operatively. These findings suggest that the use of such filters in CABG surgery may offer increased neuroprotection.
authors.affiliation: Unit of Health Psychology, Centre for Behavioural and Social Sciences in Medicine, University College London, 2nd Floor, Wolfson Building, 48 Riding House Street, W1W 7EY, London, UK.
authors.forename: Donald C
authors.initials: DC
authors.lastname: Whitaker
authors.forename: Stanton P
authors.initials: SP
authors.lastname: Newman
authors.forename: Jan
authors.initials: J
authors.lastname: Stygall
authors.forename: Chris
authors.initials: C
authors.lastname: Hope-Wynne
authors.forename: Michael J G
authors.initials: MJ
authors.lastname: Harrison
authors.forename: Robin K
authors.initials: RK
authors.lastname: Walesby
mesh_terms: D000368:Aged; D001783:Blood Flow Velocity; D003072:Cognition Disorders / Q000209:etiology / Q000517:prevention & control*; D001026:Coronary Artery Bypass / Q000009:adverse effects*; D005260:Female; D005374:Filtration; D006801:Humans; D002542:Intracranial Embolism and Thrombosis / Q000209:etiology / Q000517:prevention & control*; D007430:Intraoperative Care / Q000379:methods*; D007937:Leukapheresis / Q000379:methods*; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging / Q000503:physiopathology; D009483:Neuropsychological Tests; D011446:Prospective Studies; D014463:Ultrasonography