This paper shows the blood flow control （FwC） performance to adjust rotational speed of an ICBP （implantable centrifugal blood pump） in order to provide an adequate flow to left ventricle in different patient cond...This paper shows the blood flow control （FwC） performance to adjust rotational speed of an ICBP （implantable centrifugal blood pump） in order to provide an adequate flow to left ventricle in different patient conditions. ICBP is a totally implantable LVAD （left ventricular assist device） with ceramic bearings developed for long term circulatory assistance. FwC uses PI （proportional-integral） control to adjust rotational speed in order to provide blood flow. FwC does not use sensor for feedback, as there is an estimation system to provide blood flow measurement. Control strategy has being studied in a HCS （hybrid cardiovascular simulator） as a tool that allows the physical connection of ICBP during evaluation. In addition, HCS allows changes of some cardiovascular parameters in order to simulate specific heart disease： ejection fraction （10-25%） and heart rate （50-110 bpm）. FwC was able to adjust blood flow with steady error less than 2%. Results demonstrated that FwC is adequate to LVAD control irL different left ventricle failure conditions.展开更多
This article presents the design of a new implantable axial-flow blood pump. The special feature of the flow channel inside the blood pump is that the blood is driven by a big-small tandem impeller installed in the in...This article presents the design of a new implantable axial-flow blood pump. The special feature of the flow channel inside the blood pump is that the blood is driven by a big-small tandem impeller installed in the inner hole of the cylinder magnet of a brushless direct current motor. The inner hole makes the main flow channel possible, while the gap between the inner end of the stator and the outer end of the cylinder magnet gives the shape of the tributary flow channel. There is no motor magnet inside the main flow channel, therefore, more blood can pass through it. The gap of the tributary flow channel is very small, but the blood flow in it is not blocked. Thus, the efficiency is increased and the volume and weight of blood pump can be reduced greatly. The outer diameter, length and weight of the manufactured implantable axial-flow blood pump are 29.6 mm, 76 mm and 158 g, respectively. The impeller spins at the speed of 9000 rpm and can generate a pressure head of 100 mmHg and a flow rate of 8 L/rain. In an animal experiment, the blood pump has been successfully applied as a Ventricular Assist Device （VAD） in the chest of a small cow. Besides a mathematical model is established to simulate the flow inside an axial-flow blood pump of implantable VAD. The numerical studies on the performance of the implantable axial-flow blood pump are carried out by combining this mathematical model and the Fluent software. The numerical results agree well with those of experiments, with the maximum error less than 10%.展开更多
文摘This paper shows the blood flow control （FwC） performance to adjust rotational speed of an ICBP （implantable centrifugal blood pump） in order to provide an adequate flow to left ventricle in different patient conditions. ICBP is a totally implantable LVAD （left ventricular assist device） with ceramic bearings developed for long term circulatory assistance. FwC uses PI （proportional-integral） control to adjust rotational speed in order to provide blood flow. FwC does not use sensor for feedback, as there is an estimation system to provide blood flow measurement. Control strategy has being studied in a HCS （hybrid cardiovascular simulator） as a tool that allows the physical connection of ICBP during evaluation. In addition, HCS allows changes of some cardiovascular parameters in order to simulate specific heart disease： ejection fraction （10-25%） and heart rate （50-110 bpm）. FwC was able to adjust blood flow with steady error less than 2%. Results demonstrated that FwC is adequate to LVAD control irL different left ventricle failure conditions.
基金supported by the National High Technology Research and Development program of China (863 Program, Grant No. 2007AA02Z439)The Program for Outstanding Medical Academic Leader of Shanghai
文摘This article presents the design of a new implantable axial-flow blood pump. The special feature of the flow channel inside the blood pump is that the blood is driven by a big-small tandem impeller installed in the inner hole of the cylinder magnet of a brushless direct current motor. The inner hole makes the main flow channel possible, while the gap between the inner end of the stator and the outer end of the cylinder magnet gives the shape of the tributary flow channel. There is no motor magnet inside the main flow channel, therefore, more blood can pass through it. The gap of the tributary flow channel is very small, but the blood flow in it is not blocked. Thus, the efficiency is increased and the volume and weight of blood pump can be reduced greatly. The outer diameter, length and weight of the manufactured implantable axial-flow blood pump are 29.6 mm, 76 mm and 158 g, respectively. The impeller spins at the speed of 9000 rpm and can generate a pressure head of 100 mmHg and a flow rate of 8 L/rain. In an animal experiment, the blood pump has been successfully applied as a Ventricular Assist Device （VAD） in the chest of a small cow. Besides a mathematical model is established to simulate the flow inside an axial-flow blood pump of implantable VAD. The numerical studies on the performance of the implantable axial-flow blood pump are carried out by combining this mathematical model and the Fluent software. The numerical results agree well with those of experiments, with the maximum error less than 10%.
