title: Cerebral emboli and serum S100beta during cardiac operations.
abstract: BACKGROUND
  The glial protein S100beta has been used to estimate cerebral damage in a number of clinical settings. The purpose of this investigation was to determine the correlation between cerebral microemboli and S100beta levels during cardiac operations.
  
  
  METHODS
  Transcranial Doppler ultrasonography was used to measure emboli in the right middle cerebral artery. Emboli counts (n = 111) were divided into five time periods: (1) incision to aortic cannulation; (2) aortic cannulation to cross-clamp onset; (3) cross-clamp onset to cross-clamp release; (4) cross-clamp release to decannulation; and (5) decannulation to chest closure. The level of S100beta (n = 156) was measured at baseline, at the end of cardiopulmonary bypass, then 150 and 270 minutes after cross-clamp release.
  
  
  RESULTS
  The level of S100beta correlated with age, cardiopulmonary bypass time, cross-clamp time, and number of emboli at time period 2. Although cardiopulmonary bypass time was univariately associated with S100beta level, it became nonsignificant in a multivariable model that included age and cross-clamp time.
  
  
  CONCLUSIONS
  The correlation of S100beta level with emboli measured during cannulation (time period 2) supports the hypothesis that cannulation is a high-risk time period for cerebral injury.
authors.affiliation: Department of Anesthesiology, Duke Heart Center, Duke University Medical Center, Durham, North Carolina 27710, USA. groco001@mc.duke.edu
authors.forename: H P
authors.initials: HP
authors.lastname: Grocott
authors.forename: N D
authors.initials: ND
authors.lastname: Croughwell
authors.forename: D W
authors.initials: DW
authors.lastname: Amory
authors.forename: W D
authors.initials: WD
authors.lastname: White
authors.forename: J L
authors.initials: JL
authors.lastname: Kirchner
authors.forename: M F
authors.initials: MF
authors.lastname: Newman
mesh_terms: D000367:Age Factors; D000704:Analysis of Variance; D001011:Aorta / Q000601:surgery; D015415:Biomarkers / Q000097:blood; D002135:Calcium-Binding Proteins / Q000097:blood*; D002315:Cardiopulmonary Bypass; D002536:Cerebral Arteries / Q000000981:diagnostic imaging; D003250:Constriction; D001026:Coronary Artery Bypass / Q000009:adverse effects*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D002542:Intracranial Embolism and Thrombosis / Q000097:blood / Q000000981:diagnostic imaging / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009414:Nerve Growth Factors; D012307:Risk Factors; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins / Q000097:blood*; D013997:Time Factors; D017585:Ultrasonography, Doppler, Transcranial
chemical_list: D015415:Biomarkers; D002135:Calcium-Binding Proteins; D009414:Nerve Growth Factors; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins