Abstract: A motor rotor assembly for use in a blood pump can include a motor rotor disposed within a blood flow conduit, an inflow bearing having an inflow ball-and-cup bearing interface disposed within the blood flow conduit proximal to an inflow port of the blood flow conduit, and an outflow bearing having an outflow ball-and-cup bearing interface disposed within the blood flow conduit proximal to an outflow port of the blood flow conduit. The motor can be rotatably mounted between the inflow bearing and the outflow bearing and an outer diameter of the outflow ball-and-cup bearing interface can be larger than an outer diameter of the inflow ball-and-cup bearing interface. A motor rotor assembly for use in a blood pump incorporating aspects of the invention may improve performance, reliability and longevity of the pump. A blood pump incorporating a motor rotor can further include a motor stator. These rotors and pumps can be used in both implantable and extracorporeal blood pumps.

Abstract: The invention provides an axial flow blood pump with slanting outflow components. Specifically, the invention provides a blood pump having an angling outer stator blade edge structure in combination with a blood flow conduit having a constricting inner diameter. After constricting, the blood flow conduit can expand such that the inner diameter of the conduit increases. In addition, the blood pump can have an angling inner stator blade edge structure and a tapering stator blade hub or tapering rotor element.

Abstract: An automatic speed control system continually adjusts the speed of an implanted cardiac assist blood pump to an optimum level for the varying physiological needs of the patient. It does this by periodically iteratively incrementing the speed setpoint of the pump. When the system detects the imminence of a ventricular collapse at diastole, it decrements the speed setpoint by a predetermined safety margin. An alarm condition is provided if the setpoint decrease results in an insufficient blood flow rate through the pump. The flow rate and imminence of ventricular collapse are computed in real time as functions of only the pump's motor current and speed setpoint.

Abstract: An axial-flow blood pump has a rotor suspended in ball-and-cup bearings which are blood-cooled but not actively blood-lubricated. The ball-and-cup structures are made of highly heat-conductive material and are in heat-transferring contact with heat-conductive stator blades that serve as heat sinks for the bearings. The ball-and-cup structures are radially much smaller than the stator blades. The ball-to-cup interface has so small a gap that the ball-to-cup structures present an essentially continuous surface to the blood flow.

Abstract: An automatic speed control system continually adjusts the speed of an implanted cardiac assist blood pump to an optimum level for the varying physiological needs of the patient. It does this by periodically iteratively incrementing the speed setpoint of the pump. When the system detects the imminence of a ventricular collapse at diastole, it decrements the speed setpoint by a predetermined safety margin. An alarm condition is provided if the setpoint decrease results in an insufficient blood flow rate through the pump. The flow rate and imminence of ventricular collapse are computed in real time as functions of only the pump's motor current and speed setpoint.

Abstract: An axial-flow blood pump has a rotor suspended in ball-and-cup bearings which are blood-cooled but not actively blood-lubricated. The ball-and-cup structures are made of highly heat-conductive material and are in heat-transferring contact with heat-conductive stator blades that serve as heat sinks for the bearings. The ball-and-cup structures are radially much smaller than the stator blades. The ball-and-cup interface has so small a gap that the ball-to-cup structures present an essentially continuous surface to the blood flow.

Abstract: An implantable electric blood pump has a motor stator defining a cylindrical blood conduit, and a pump rotor in which the motor rotor is embedded. The pump rotor is conical at each of its ends and terminates at each end in a ball-and-cup structure washed directly by the pumped blood stream. Grooves may be formed in the ball-and-cup structure to enhance the heat-removing washing action of the blood stream. The pump rotor is nested in the stator blades to shorten the pump and wash the outlet bearing with a partially circumferential blood flow. Titanium-titanium carbide facing alumina are the preferred materials for the rotary-stationary interface, and the gap of the rotary-stationary interface is kept so small that no significant amount of blood serum can penetrate between the mating surfaces of the interface.

Abstract: An implantable ventricular assist system uses a small high-speed axial flow blood pump which may be grafted into the patient's circulatory system. The pump includes a blood tube in which the pump rotor and stator are coaxially contained, and a motor stator surrounding the blood duct. A permanent magnet motor rotor is integral with the pump rotor. Purge fluid for the hydrodynamic bearings of the device and power for the motor are preferably percutaneously introduced from extracorporeal sources worn by the patient. The purge fluid is introduced into the pump stator blades. This construction avoids the creation of discontinuities in the blood path wall due to the routing of drive power and/or fluid supply elements through the blood path wall. The described construction greatly reduces the size of the implant needed for a given blood flow rate and enhances its physiological compatibility with the body.

Abstract: A miniature high-speed intravascular blood pump is formed as a single stage with two rows of rotor blades and a single row of stator blades within a tubular housing. The rotor's first row produces a mixed centrifugal and axial flow, while the rotor's second row produces a purely axial flow. The blades of the second row are shaped so as to produce a uniform blood flow along the trailing edges of the blades. For this purpose, the bases of the outer trailing edges of the second row blades have a negative propulsion angle. The pump has a purge-sealed hydrostatic bearing which is spring-loaded for minimum gap. The pump is driven by a cable encased in a dual-lumen, fluid-filled cable sheath formed of a coextrusion of a soft, blood-compatible outer layer and a stiff, abrasion-resistant inner layer. The cable sheath serves both as a purge fluid supply for the bearing, and as a means for flushing abraded debris away from the pump.

Abstract: An opposing vortex oscillator is used to control the frequency and duty cycle of a high-frequency jet ventilator for trauma management in acute and uncontrolled situations where no power other than the pressure of the ventilation gas itself is available. Frequency adjustment is achieved by connecting variable volumes to one inlet of the oscillator while duty cycle control is achieved by supplying fluid to one inlet of the oscillator through a variable-orifice bias control valve. Safety means are provided to automatically disable the ventilator in case of airway blockage.