title: Non-occlusive condition with the Better-Header roller pump: impacts of flow dynamics and hemolysis.
abstract: OBJECTIVE
  Impacts on hemolysis and backflow using a non-occlusive setting with the Better-Header (BH) roller pump were investigated.
  
  
  RESULTS
  Pump flow of a non-occlusion setting was measured with a pump speed of 3 L/min and 5 L/min against various after-loads. With the non-occlusive setting (BH-NO350), backflow was less than 10% if the pump pressure head was <300 mmHg. When the outlet line is occluded, 80% of the set flow was shunted through the pressure relief valve and outlet pressure did not develop hazardous overpressure. During surgery with the BH-NO350, flow loss was <5% while the pump pressure was maintained at approximately 200 mmHg. An in vitro hemolysis test was conducted at 5 L/min against 350 mmHg, using the standard occlusion (BH-SO), the non-occlusion (BH-NO350), and the centrifugal pump (CP). The CP demonstrated less hemolysis than the other two groups; the BH-SO and the BH-NO350 had similar hemolytic characteristics. During cardiopulmonary bypass, no significant differences in hemolysis were seen among the BH-SO, the BH-NO350, and the CP.
  
  
  CONCLUSIONS
  Possible flow loss of the non-occlusion setting with the BH should be almost negligible in most clinical situations. The BH-NO350 demonstrated hemolytic characteristics similar to those of the BH-SO, but not as good as those of the CP.
authors.affiliation: Department of Surgery, Kurume University School of Medicine, Fukuoka, Japan.
authors.forename: Eiki
authors.initials: E
authors.lastname: Tayama
authors.forename: Hideki
authors.initials: H
authors.lastname: Teshima
authors.forename: Tohru
authors.initials: T
authors.lastname: Takaseya
authors.forename: Shuji
authors.initials: S
authors.lastname: Fukunaga
authors.forename: Kei-ichiro
authors.initials: K
authors.lastname: Tayama
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Hayashida
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Akashi
authors.forename: Takemi
authors.initials: T
authors.lastname: Kawara
authors.forename: Shigeaki
authors.initials: S
authors.lastname: Aoyagi
mesh_terms: D001794:Blood Pressure; D002315:Cardiopulmonary Bypass / Q000295:instrumentation*; D001026:Coronary Artery Bypass / Q000295:instrumentation; D003326:Coronary Circulation; D003327:Coronary Disease / Q000503:physiopathology / Q000601:surgery*; D005112:Extracorporeal Circulation / Q000295:instrumentation; D006461:Hemolysis; D006801:Humans