title: Inlet port positioning for a miniaturized centrifugal blood pump.
abstract: We are developing the Baylor-Kyocera KP implantable centrifugal blood pump for small sized adult and pediatric patients. This pump eccentrically positions the inlet port, which eliminates flow stagnation around the top pivot bearing. The inlet port design is important because it may vary the inlet orifice pressure on the top housing and change hydraulic performance and hemolytic characteristics. The pressure distribution inside the KP pump was assessed by a computational fluid dynamic (CFD) analysis with 2.7 x 10(5) elements and 3.16 x 10(5) nodes. Hydraulic performance and hemolysis were evaluated with 3 different pump housings, which had 3.8, 4.5, and 6.1 mm offset inlet ports from the center in a mock circuit. The CFD analysis revealed that the pressure gradually increased from the center toward the peripheral. The pressure difference between the 3.8 to 6.1 mm offsets was less than 600 Pa. The hydraulic performance did not drastically change at 3.8, 4.5, and 6.1 mm offset from the center. However, the hemolysis increased with the increase of the port offset from 0.0080+/- 0.0048 to 0.054 +/- 0.028 g/100 L. The inlet port positioning is important to attain less blood trauma in this small Gyro centrifugal blood pump. The preferable position of the inlet port is less than 4.5 mm offset from the center.
authors.affiliation: Baylor College of Medicine, Department of Surgery, Houston, Texas, USA. ttakano@bcm.tmc.edu
authors.forename: Tamaki
authors.initials: T
authors.lastname: Takano
authors.forename: Sebastian
authors.initials: S
authors.lastname: Schulte-Eistrup
authors.forename: Shinji
authors.initials: S
authors.lastname: Kawahito
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Maeda
authors.forename: Kenji
authors.initials: K
authors.lastname: Nonaka
authors.forename: Joerg
authors.initials: J
authors.lastname: Linneweber
authors.forename: Julie
authors.initials: J
authors.lastname: Glueck
authors.forename: Akira
authors.initials: A
authors.lastname: Fujisawa
authors.forename: Kenzo
authors.initials: K
authors.lastname: Makinouchi
authors.forename: Michihiro
authors.initials: M
authors.lastname: Yokokawa
authors.forename: Yukihiko
authors.initials: Y
authors.lastname: Nosé
mesh_terms: D002498:Centrifugation; D004867:Equipment Design; D006353:Heart-Assist Devices; D006801:Humans