title: Optimal moving angle of pusher plate in occlusive-type pulsatile blood pump.
abstract: Since the occlusive-type pulsatile extracorporeal blood pump (Twin-Pulse Life Support System; Seoul National University, Seoul, Korea) received the CE mark of the European Directives and Korea Food and Drug Administration approval (2004) for short-term applications as an extracorporeal life support system, the pump system has been tested for hemolysis. This pump system was recently upgraded with an ameliorated pusher plate to reduce hemolysis. In this study, numerical analysis and in vitro tests were performed to determine the optimal conditions for increasing the durability of the blood sac and pump output. During the simulation, the minimum sliding interface force (SIF) for the angle of the pusher plate movement (PPM) was calculated (40-70 degrees ). In the in vitro durability test, the angle of the PPM was increased gradually from 40 to 70 degrees in 10 degrees increments, and the mean time to failure (MTTF) of the blood sac was calculated. Fifteen tests were conducted for each case: 40, 50, 60, and 70 degrees (n = 15 each). The MTTF of the blood sac was defined as the time when a crack of the blood sac occurred. The longer lifetime of the blood sac at 60 degrees of the PPM (297.0 h) than that at 50 degrees (197.6 h) was attributed to the lower SIF value (-0.13, normalized value) at 60 degrees of the PPM.
authors.affiliation: Department of Biomedical Engineering, Brain Korea 21 Project for Biomedical Science, College of Medicine, Korea University, Seoul, Korea.
authors.forename: Hyuk
authors.initials: H
authors.lastname: Choi
authors.forename: Hwansung
authors.initials: H
authors.lastname: Lee
authors.forename: Jaesoon
authors.initials: J
authors.lastname: Choi
authors.forename: Jung Joo
authors.initials: JJ
authors.lastname: Lee
authors.forename: Kyoung Won
authors.initials: KW
authors.lastname: Nam
authors.forename: Jun Woo
authors.initials: JW
authors.lastname: Park
authors.forename: Yongdoo
authors.initials: Y
authors.lastname: Park
authors.forename: Kyung
authors.initials: K
authors.lastname: Sun
authors.forename: Heung-Man
authors.initials: HM
authors.lastname: Lee
mesh_terms: D001243:Assisted Circulation / Q000295:instrumentation*; D004867:Equipment Design; D004868:Equipment Failure; D011673:Pulsatile Flow