title: Synthetic protein treated versus heparin coated cardiopulmonary bypass surfaces: similar clinical results and minor biochemical differences.
abstract: OBJECTIVE
  Complications associated with cardiopulmonary bypass (CPB) have gained more attention due to increased interest in coronary artery bypass grafting without CPB. The impact of heparin coating of CPB circuits has been discussed controversially. The present study examines if the treatment of the oxygenator surface with a synthetic protein may serve as an alternative to a completely heparin coated circuit.
  
  
  METHODS
  Fifty-eight patients undergoing coronary artery bypass grafting with CPB were randomly assigned to completely heparin coated circuits or synthetic protein treated oxygenators in a double blind protocol, focussing on the inflammatory reaction resulting in membrane damage, coagulation changes and markers of cerebral injury or dysfunction. Treatment groups did not differ as to preoperative demographics, and intraoperative clinical data. Patients with any neurologic disease or risk factors for cerebral dysfunction were not included in the study.
  
  
  RESULTS
  Postoperative clinical data did not differ between groups. Both surface treatments resulted in similar coagulation activation, hyperfibrinolysis and disseminated intravascular coagulation. Platelet count displayed a difference in favour of the heparin coated group (P = 0.029). Increased leukocyte activation reflected by rising myeloperoxidase concentrations on CPB was present in both synthetic protein and heparin coating groups. Interleukins 6 and 8 reacted similarly, but interleukin 8 increased significantly more (P = 0.0061) at the end of surgery in patients treated with protein treated oxygenators. The same pattern was observed for complement activation as determined by total complement complex (P = 0.006). Both surface changes resulted in moderately increased S-100B protein and neuron specific enolase, without difference between groups. Both markers did not reach concentrations associated with clinical manifestation of cerebral injury.
  
  
  CONCLUSIONS
  These results in routine patients with short bypass time, imply that protein treated oxygenators are associated with a limited increase of biochemical markers similar to heparin coating. However, significantly lower interleukin 8 release and complement activation can be achieved by heparin coating. The protein treatment is a standard feature of the oxygenator examined in both groups. It is not associated with additional cost and therefore appropriate for use in routine patients.
authors.affiliation: Department of Thoracic and Cardiovascular Surgery (Klinik für Thorax, Herz- und Gefässchirurgie), Johann Wolfgang Goethe University, Frankfurt/Main, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Wimmer-Greinecker
authors.forename: G
authors.initials: G
authors.lastname: Matheis
authors.forename: S
authors.initials: S
authors.lastname: Martens
authors.forename: G
authors.initials: G
authors.lastname: Oremek
authors.forename: U
authors.initials: U
authors.lastname: Abdel-Rahman
authors.forename: A
authors.initials: A
authors.lastname: Moritz
mesh_terms: D000368:Aged; D000925:Anticoagulants; D015415:Biomarkers / Q000097:blood; D002315:Cardiopulmonary Bypass / Q000295:instrumentation*; D020099:Coated Materials, Biocompatible; D001026:Coronary Artery Bypass; D003402:Creatine Kinase / Q000097:blood; D004311:Double-Blind Method; D005260:Female; D006493:Heparin; D006801:Humans; D007527:Isoenzymes; D008297:Male; D008875:Middle Aged; D010107:Oxygenators, Membrane; D010976:Platelet Count; D011183:Postoperative Complications / Q000097:blood* / Q000517:prevention & control; D011446:Prospective Studies; D011506:Proteins; D009418:S100 Proteins / Q000097:blood; D020107:Troponin T / Q000097:blood
chemical_list: D000925:Anticoagulants; D015415:Biomarkers; D020099:Coated Materials, Biocompatible; D007527:Isoenzymes; D011506:Proteins; D009418:S100 Proteins; D020107:Troponin T; D006493:Heparin; D003402:Creatine Kinase