title: Miniaturized cardiopulmonary bypass in coronary artery bypass surgery: marginal impact on inflammation and coagulation but loss of safety margins.
abstract: OBJECTIVE
  Inflammation and coagulation disturbances are common consequences of cardiopulmonary bypass (CPB). Recently, miniaturized closed CPB circuits without cardiotomy suction and venous reservoir have been proposed to reduce complication rates. We compared outcomes with conventional (CCPB) and miniaturized cardiopulmonary bypass (MCPB) after coronary artery bypass operations (CABG) with respect to inflammation and coagulation.
  
  
  METHODS
  Thirty patients (23% female; aged 67.9 +/- 9.0 years) were prospectively randomly assigned to undergo isolated CABG with CCPB or MCPB. Conventional CPB had a pump prime of 1, 600 mL. Miniaturized CPB consisted of a centrifugal pump, arterial filter, heparinized tubing, and oxygenator with a priming volume of 800 mL. Shed blood was removed by a cell-saving device and reinfused. Measurements included interleukin (IL)-2 receptor, IL-6, IL-10, tumor necrosis factor receptor 55 and 75, C reactive protein, leukocyte differentiation, d-dimers, fibrinogen, and thrombocytes at six time points.
  
  
  RESULTS
  In both groups no major complication occurred. However, two dangerous air leaks occurred in the closed MCPB circuit, demonstrating the narrow safety margins. Operative handling was also more difficult owing to limitations in venting and fluid management. International normalized ratio (p = 0.03) and antithrombin III (p = 0.04) levels were elevated during CPB in the CCPB group, most likely owing to differences of the intraoperative anticoagulation management. Repeated measures analysis revealed that not a single parameter of inflammation or clinical outcome showed significant differences among groups.
  
  
  CONCLUSIONS
  Use of a MCPB affected inflammation and coagulation variables only marginally and did not lead to clinical relevant changes as assessed by blood loss, need for blood products, and intensive care unit and clinical stays. However, safety margins for volume loss, air emboli, and weaning from CPB decrease, because of the closed MCPB circuit.
authors.affiliation: Clinic of Cardiac Surgery, University of Munich, Munich, Germany. georg.nollert@med.uni-muenchen.de
authors.forename: Georg
authors.initials: G
authors.lastname: Nollert
authors.forename: Ina
authors.initials: I
authors.lastname: Schwabenland
authors.forename: Deniz
authors.initials: D
authors.lastname: Maktav
authors.forename: Felix
authors.initials: F
authors.lastname: Kur
authors.forename: Frank
authors.initials: F
authors.lastname: Christ
authors.forename: Peter
authors.initials: P
authors.lastname: Fraunberger
authors.forename: Bruno
authors.initials: B
authors.lastname: Reichart
authors.forename: Calin
authors.initials: C
authors.lastname: Vicol
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001778:Blood Coagulation Disorders / Q000453:epidemiology / Q000209:etiology*; D002315:Cardiopulmonary Bypass / Q000009:adverse effects* / Q000379:methods*; D001026:Coronary Artery Bypass; D005260:Female; D006801:Humans; D007249:Inflammation / Q000453:epidemiology / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D008904:Miniaturization; D011446:Prospective Studies