title: Clinical application of vacuum-assisted cardiopulmonary bypass with a pressure relief valve.
abstract: OBJECTIVE
  Hemodilution induced by cardiopulmonary bypass (CPB) often prevents open heart operations without blood transfusion because of a large CPB-priming volume. A vacuum-assisted venous drainage system appears to overcome this problem and our previous experimental study demonstrated the beneficial effect of a vacuum-assisted CPB with a pressure relief valve. In this study, we clinically applied this novel system, and evaluated its efficacy by comparing it with the results of a conventional siphon-dependent drainage system.
  
  
  METHODS
  Sixty patients undergoing open heart operation were divided into Group V (vacuum-assisted system, n=30) and Group S (siphon-dependent system, n=30). The vacuum-assisted system contains a powerful vacuum generator and a pressure relief valve to keep the negative pressure in the reservoir constant when the blood suction is used.
  
  
  RESULTS
  The CPB-priming volume was significantly smaller in Group V (V vs. S: 1071+/-88 vs. 1405+/-137 ml; P<0.01), resulting in the lower hemodilution in Group V evidenced by the minimum hemoglobin level (V vs. S: 6.83+/-1.06 vs. 5.78+/-0.79 mg/dl; P<0.01) and blood transfusion rate (V vs. S: 9 vs. 20%; P<0.01). There were no significant differences in the plasma free hemoglobin level and the reduction ratio of plasma haptoglobin between the groups.
  
  
  CONCLUSIONS
  These data demonstrate that this vacuum-assisted CPB can provide simplification of the CPB circuit, resulting in a smaller CPB-priming volume and lower hemodilution. This vacuum-assisted CPB may attenuate the negative effect of CPB by minimizing hemodilution and appears to be a useful modification to accomplish no blood-requiring open heart operations.
authors.affiliation: Department of Surgery, Course of Interventional Medicine (E1), Osaka University Graduate School of Medicine, 2-2 Yamada-oka, Suita City, 565-0871, Osaka, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Hayashi
authors.forename: K
authors.initials: K
authors.lastname: Kagisaki
authors.forename: T
authors.initials: T
authors.lastname: Yamaguchi
authors.forename: T
authors.initials: T
authors.lastname: Sakaguchi
authors.forename: Y
authors.initials: Y
authors.lastname: Naka
authors.forename: Y
authors.initials: Y
authors.lastname: Sawa
authors.forename: S
authors.initials: S
authors.lastname: Ohtake
authors.forename: H
authors.initials: H
authors.lastname: Matsuda
mesh_terms: D001803:Blood Transfusion; D006348:Cardiac Surgical Procedures; D002315:Cardiopulmonary Bypass / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D005260:Female; D006438:Hemodilution; D006454:Hemoglobins / Q000032:analysis; D006461:Hemolysis; D006801:Humans; D008297:Male; D008875:Middle Aged; D014618:Vacuum
chemical_list: D006454:Hemoglobins