A prospective clinical study of cerebral microemboli and neuropsychological outcome comparing vent-line and auto-venting arterial line filters: both filters are equally safe.
BACKGROUND
Microemboli are the main implicated cause of neuropsychological (NP) impairment after cardiac surgery. This prospective clinical trial compared the effect of an auto-venting arterial line filter on intraoperative cerebral microemboli and NP outcome compared to an arterial line filter with a vent line, in patients undergoing elective coronary artery bypass graft (CABG) surgery.


METHODS
One hundred and ten patients received either an Avecor Affinity (n =73) or Pall AV-6 (n =37) control filter. Cerebral microemboli during cardiopulmonary bypass were recorded by transcranial Doppler monitoring of the right middle cerebral artery. Evidence of cerebral impairment was obtained by comparing patients' performance in a NP test battery (nine tests) administered 6-8 weeks postoperatively with their preoperative scores.


RESULTS
During cardiopulmonary bypass, the median number and range of microemboli were 67 (5-846) and 55 (2-773) for the Avecor and AV-6 groups, respectively (p = 0.47). There was no difference in NP outcome.


CONCLUSIONS
There is no difference in the filtering ability of vent-line and auto-vent filters as assessed by cerebral microemboli. This, together with the similar NP outcome, suggests that both types of filter are equally safe for clinical use.
Whitaker
Donald C
DC
Centre for Behavioural and Social Sciences in Medicine, University College London, UK.
Stygall
Jan
J
Hope-Wynne
Chris
C
Walesby
Robin K
RK
Harrison
Michael J G
MJ
Newman
Stanton P
SP
D000368:Aged; D005112:Extracorporeal Circulation / Q000009:adverse effects / Q000295:instrumentation*; D005260:Female; D005374:Filtration / Q000295:instrumentation; D006801:Humans; D020766:Intracranial Embolism / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000517:prevention & control*; D008297:Male; D008875:Middle Aged; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging; D009483:Neuropsychological Tests; D011446:Prospective Studies; D016896:Treatment Outcome; D017585:Ultrasonography, Doppler, Transcranial / Q000379:methods