title: Inflammatory mediators in adults undergoing cardiopulmonary bypass: comparison of centrifugal and roller pumps.
abstract: BACKGROUND
  The nonocclusive centrifugal pump is used for cardiopulmonary bypass (CPB) and mechanical cardiac assistance. This study examined its impact on proinflammatory cytokine release.
  
  
  METHODS
  Forty-one patients undergoing elective coronary artery bypass grafting were randomized prospectively to either a standard roller pump group (n = 21) or a centrifugal vortex pump group (n = 20) for CPB. The two groups were well matched in age, sex, severity of disease, and duration of CPB and aortic cross-clamping. Plasma levels of the cytokines tumor necrosis factor-alpha, interleukin-1beta, interleukin-6, and interleukin-8, as well as terminal complement, neutrophil counts, and leukocyte elastase, were analyzed before, during, and after CPB.
  
  
  RESULTS
  In both groups, traces of tumor necrosis factor-alpha were observed infrequently and interleukin-1beta was not detected. Plasma levels of interleukin-6 and interleukin-8 increased during and after CPB, reaching a peak at 2 hours after protamine administration in both groups before returning toward baseline at 24 hours. The release of interleukin-6 was significantly greater in the centrifugal group (p < 0.05), whereas the interleukin-8 concentration did not differ between the groups throughout the study period. Levels of terminal complement increased in both groups perioperatively, reaching a peak 30 minutes after protamine administration, whereas neutrophil counts and elastase peaked 2 hours after protamine administration. Plasma terminal complement, neutrophil counts, and elastase release were significantly higher in the centrifugal group (p < 0.05). Peak terminal complement correlated (r = 0.64, p < 0.01) with peak elastase in the centrifugal group only.
  
  
  CONCLUSIONS
  This study confirms the proinflammatory nature of CPB in adults and demonstrates that use of the centrifugal pump induces a greater systemic inflammatory response than use of the standard roller pump.
authors.affiliation: Cardiothoracic Department, Killingbeck Hospital, Leeds, United Kingdom.
authors.forename: S
authors.initials: S
authors.lastname: Ashraf
authors.forename: J
authors.initials: J
authors.lastname: Butler
authors.forename: Y
authors.initials: Y
authors.lastname: Tian
authors.forename: D
authors.initials: D
authors.lastname: Cowan
authors.forename: S
authors.initials: S
authors.lastname: Lintin
authors.forename: N R
authors.initials: NR
authors.lastname: Saunders
authors.forename: K G
authors.initials: KG
authors.lastname: Watterson
authors.forename: P G
authors.initials: PG
authors.lastname: Martin
mesh_terms: D000328:Adult; D000368:Aged; D002315:Cardiopulmonary Bypass / Q000295:instrumentation*; D015938:Complement Membrane Attack Complex / Q000032:analysis; D005260:Female; D006801:Humans; D018836:Inflammation Mediators / Q000097:blood*; D007378:Interleukins / Q000097:blood; D007958:Leukocyte Count; D019272:Leukocyte Elastase / Q000097:blood; D008297:Male; D008875:Middle Aged; D009504:Neutrophils; D011446:Prospective Studies; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis
chemical_list: D015938:Complement Membrane Attack Complex; D018836:Inflammation Mediators; D007378:Interleukins; D014409:Tumor Necrosis Factor-alpha; D019272:Leukocyte Elastase