Abstract: An apparatus for driving an intra-aorta balloon pump is comprised of an isolator having a housing in which a first chamber and a second chamber are defined by a membrane, a positive pressure source which is in fluid communication with the first chamber via a first timing valve, a negative pressure source which is in fluid communication with the first chamber via a second timing valve, a space defined between the second chamber and the intra-aorta balloon pump and containing an amount of operating fluid, a tank for storing therein the operating fluid, an inlet valve interposed between the tank and the space, an exhaust valve interposed between the space and the atmospheric pressure, a sensor for measuring the pressure in the space, and a controller to be operated in such a manner that the first timing valve and the second timing valve are opened and closed alternately in order to establish an alternate supply of the positive and negative pressures to the first chamber and each time-duration during which the fi

Abstract: The invention is directed to a leak detector for an intra-aorta balloon pump which has a pressure source for pressurizing a primary fluid, a balloon filled with a secondary fluid and inflated thereby, and an isolating device which includes a diaphragm for defining a primary chamber and secondary chamber within the device. The primary chamber is communicated with the pressure source and supplied with the primary fluid, and the secondary chamber is communicated with the balloon and filled with the secondary fluid. The leak detector includes a sensor for detecting a relative position of the diaphragm against at least an inner surface of one of the primary chamber and secondary chamber, and determines a leak of the secondary fluid in response to the relative position of the diaphragm detected by the sensor.

Abstract: Apparatus for driving a medical appliance has a single compressor for generating both the positive and the negative pressures. Positive and negative pressure valves for controlling communication with the atmosphere are connected to the outlet and inlet terminals of the compressor and the outlet and inlet terminals of the compressor are also connected to a positive pressure accumulator and a negative pressure accumulator, respectively. The apparatus has pressure sensors to sense when the pressures in the accumulators reach a set pressure. The apparatus further has a one-way valve in the positive pressure line between the compressor and the valve or in the negative pressure line between the compressor and the valve. The apparatus prohibits the positive and negative pressure valves from being open at the same time.

Abstract: A pumping unit is disclosed which alternately applies a positive and a negative pressure, both of given values, to aa drive chamber of an artificial heart. In a first and a second embodiment, air of an elevated pressure which is discharged by an air compressor is fed through a positive pressure accumulator and a positive pressure open/close valve to the drive chamber, and a negative pressure from an air decompressor is fed through a negative pressure accumulator and the negative pressure open/close valve to the drive chamber. Alternating open periods are assigned to the positive and the negative pressure open/close valve. During the open period, each valve is opened and closed in a manner corresponding to the prevailing pressure in the drive chamber so as to maintain the pressure at a constant value.

Abstract: Apparatus for driving a medical appliance has a single compressor for generating both the positive and negative pressures. The switching valves are connected to the outlet and inlet terminals of the compressor. The outlet and inlet terminals of the compressor are also connected to the positive pressure accumulator and the negative pressure accumulator, respectively. The apparatus has the pressure sensors to sense the pressures in the positive and negative pressure accumulators. When the pressure in the accumulator reaches a set pressure, at least one of the switching valves is closed. The apparatus further has the relief valves connected to the outlet and inlet terminals of the compressor. These relief valves open when the pressures of the compressor become excessive.

Abstract: A fluid isolator is used to separate a drive gas from a drive air. A pulsation in the air pressure is produced to drive a balloon pump placed within the aorta through the drive gas. The gas pressure on the secondary side is determined as the air pressure applied to the primary side of the isolator is a positive pressure, and the quantity of gas on the secondary side is automatically regulated in accordance with a result of such determination. The gas pressure may be controlled so as to coincide with a target value, or alternatively, the quantity of gas may be controlled in accordance with a difference between the gas pressure and the blood pressure of a physical body.

Abstract: A medical appliance driving apparatus has pressure regulating control valves connected to positive and negative pressure sources and an isolator having an input chamber and an output chamber which are defined by a moveable membrane. The input chamber is connected to the pressure regulating control valves. An output valve is connected to the output chamber of the isolator, and a microcomputer is provided for switching the control valves to the positive pressure side or the negative pressure side and controlling the operation of the output valve. When the control valves are activated to provide positive pressure the output valve is opened, the positive pressure which is supplied to the input chamber causes the moveable membrane to move in a direction in which the medical appliance is inflated.

Abstract: An intra-aortic balloon pump apparatus includes a first catheter one end of which is secured to a connector having a gas supply port, a balloon one end of which is secured to the distal end of the first catheter, a central tubular member the distal end of which projects from the distal end of the first catheter and to which the distal end of the balloon is fixedly secured, a second catheter freely insertable into the central tubular member and having a distal end provided with an arterial pressure transduceer, and a second connector to which the other end of the second catheter is secured for feeding a signal from the pressure transducer to the outside of the apparatus. After the balloon, central tubular member and first catheter are placed into the aorta, the second catheter having the pressure transducer at its distal end is inserted through the interior of the central tubular member into the aorta.

Abstract: A cannula for infusion of blood into a blood vessel includes a flexible membrane member which is secured to the leading end of a blood admitting pipe. An end insert is secured to the leading end of the flexible membrane member, and a core member is fixedly connected to the end insert. A fluid passage opening is formed in either the end insert or the flexible membrane member so as to permit the discharge of a blood which is infused into the flexible membrane member from an external source through the blood admitting pipe. The flexible membrane member may be folded and wrapped around the core member when the cannula is to be inserted into a blood vessel. As the blood begins to be fed into the pipe, the flexible membrane member is caused to be inflated, and blood flows into a blood vessel from the flexible membrane member.

Abstract: With a driving system being separated by a diaphragm into two sections, a predetermined pressure is applied to the primary side of the diaphragm using air and helium gas or the like is used on the secondary side of the diaphragm, so that the pressure on the primary side of the diaphragm is transmitted to an artificial heart or the like connected to the secondary side thereof. Independently of a control system for maintaining the output from a pressure sensor to a predetermined value at all times, a solenoid valve for directly providing a higher pressure produced by a compressor or the like at the given drive timing is provided in a pressure regulating system, thereby causing a sharp rise in drive of the diaphragm. In an operation mode for automatically exhausting air from the secondary side of the diaphragm, the higher and lower pressures are alternately applied to the secondary side with the primary side being subject to the lower pressure, thus replacing air by another gas.