Optimal moving angle of pusher plate in occlusive-type pulsatile blood pump.
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.
Choi
Hyuk
H
Department of Biomedical Engineering, Brain Korea 21 Project for Biomedical Science, College of Medicine, Korea University, Seoul, Korea.
Lee
Hwansung
H
Choi
Jaesoon
J
Lee
Jung Joo
JJ
Nam
Kyoung Won
KW
Park
Jun Woo
JW
Park
Yongdoo
Y
Sun
Kyung
K
Lee
Heung-Man
HM
D001243:Assisted Circulation / Q000295:instrumentation*; D004867:Equipment Design; D004868:Equipment Failure; D011673:Pulsatile Flow