Abstract: A blood processing system is described in which blood pressure readings obtained before and after passage of blood aspirated from an operative site through a membrane separator is used by a programmed controller to determine the hematocrit level of the blood and to add saline solution to adjust the hematocrit level to a desired level. The blood processing system contains a distributor cap to distribute wash solution to the inside of a filter to wash out additional blood cellular material within the filter. A precollector may be used remotely from the site of the blood processing system and later joined with the system to withdraw blood contained in the precollector for processing by the blood processing system.

Abstract: Blood is pumped by a pump, preferably a bi-concave diaphragm pump. When the blood pump is full of blood, this full condition is detected and a batch of blood is emptied completely from the pump for delivery to the patient. A second pump, also preferably a bi-concave diaphragm pump, pumps anti-coagulant into the blood as it is recovered. This second pump ejects its contents every time the blood pump ejects its contents. Particulates in the blood are removed by a filter and air is removed by a defoamer. Fluid and very small matter in the blood may be removed in a tangential flow separator. Blood flows through a narrow passage along one or more membranes, with fluid and small matter passing through the membrane(s). A washing fluid may be added to blood within this separator. A third pump, again preferably a bi-concave diaphragm pump, is used to add this washing fluid. The third pump is emptied whenever the blood pump empties, and thereafter refills with washing fluid.

Abstract: A blood gas detector for human use has a support fitting into the mouth between the sides of the upper and lower jaws and the inside of the cheek and carries electric conductors for connection to an external indicator affording response to blood gas present at the inside of the cheek. The detector may also have an electric heater on the support fitting.

Abstract: An engine has preferably coupled together a reciprocating air compressor discharging through a heat exchanger into a reciprocating cylinder piston combination, the flow into the piston cylinder combination being controlled by a cam-actuated inlet valve which is maintained open for a substantial fraction of the out-stroke of the combustion piston. There is also an exhaust valve from the combustion chamber which releases exhaust gas to the heat exchanger for transfer of thermal energy to the incoming compressed air. A fuel injector supplies fuel to the compressed air entering through the inlet valve into the combustion chamber over a large part of the out-stroke of the power piston.

Abstract: A cardiac prosthesis having an hydraulically actuated compressible blood pump. An actuation chamber adjacent the blood pump receives hydraulic actuation fluid from an actuator pump through a three-way ventricular dump valve to compress the blood pump during systole and eject blood therefrom. During diastole the actuation fluid is permitted to drain from the actuation chamber through the three-way valve into a reservoir.

Abstract: A cardiac prosthesis having a hydraulically actuated compressible blood pump. An actuation chamber adjacent the blood pump receives hydraulic actuation fluid from an actuator pump through a three-way ventricular dump valve to compress the blood pump during systole and eject blood therefrom. During diastole the actuation fluid is permitted to drain from the actuation chamber through the three-way valve into a reservoir. The valve includes inlet and outlet manifolds and synchronously movable valve members within each manifold for controlling the flow of actuation fluid into and out of the actuation chamber.

Abstract: A total cardiac prosthesis having a pair of hydraulically actuated compressible blood pumps. An actuation chamber adjacent each blood pump receives hydraulic actuation fluid from a separate actuator pump to compress the blood pump during systole and eject blood therefrom. During diastole the actuation fluid is permitted to drain from the actuation chamber into a reservoir. One of the actuator pumps delivers actuation fluid to its associated actuation chamber through a three-way ventricular dump valve, which directs fluid directly to the reservoir during diastole. The other actuator pump is a reversible pump which repeatedly reverses its pumping direction to effect systole and diastole in its associated blood pump.

Abstract: A cardiac prosthesis having a hydraulically actuated compressible blood pump. An actuation chamber adjacent the blood pump receives pulses of hydraulic actuation fluid from an actuator pump through a fluid inlet path to compress the blood pump during systole and eject blood therefrom. Between pulses the actuation fluid is permitted to drain from the actuation chamber through an outlet path into a reservoir. Discharge of fluid through the outlet path is controlled by a dump valve which is adapted to close or open the outlet path primarily in response to forces which vary as a function of the flow of actuation fluid through the fluid inlet path.

Abstract: A cardiac prosthesis having a hydraulically actuated compressible blood pump. An actuation chamber adjacent the blood pump receives pulses of hydraulic actuation fluid from an actuator pump through a fluid inlet path to compress the blood pump during systole and eject blood therefrom. Between pulses the actuation fluid is permitted to drain from the actuation chamber through an outlet path into a reservoir. Discharge of fluid through the outlet path is controlled by a dump valve which is adapted to close or open the outlet path primarily in response to forces which vary as a function of the flow of actuation fluid through the fluid inlet path.

Abstract: A vapor engine including a cylinder in which a piston reciprocates and having an inlet valve in the cylinder head which is driven from its seat by the piston as it approaches the cylinder head. The time at which the valve is driven from its seat does not change relative to the top dead center position of the piston. The travel of the valve body is ballistic and the valve remains open for a time determined by a combination of the piston velocity at the initial contact, the distance the valve travels before hitting a stop from which it rebounds elastically toward its seat, the pressure drop across the valve and the mass of the valve. The exhaust valve of the engine may be either internal and actuated by mechanical forces or external, in which case it is actuated by pressure forces. In one embodiment of the invention the stop from which the valve rebounds may be adjustably positioned manually or automatically to control the period of time during which the intake valve is open.

Abstract: A spirometer has a housing with a wall having an opening therein. A bag made up of a first, stiff sheet and a second, flexible sheet having an exhaust slit therein as well as an inlet tube is supported within the housing with the first sheet lying against the wall and with the inlet tube extending through the opening. A valve flap within the bag overlies the inlet tube and a valve bar in the housing is spring urged with a selected force to press the bag, between the slit and the tube, against the wall. A primary plate is hinged to the housing at its top to lie against the second sheet. A secondary plate is similarly hinged and is power controlled to be spaced from or to press against the primary plate through an intervening cushion. The position of the primary plate is indicated mechanically and also by electrical instrumentation.

Abstract: A volume ventilating respirator, especially for infant and pediatric use, has a pair of different size volume chambers with means for selecting one or the other for specific use. There is a selector affording a choice of several different ventilating modes including deep breaths at chosen periods or events. The operation is generally automatic with response to patient effort, if desired, and has some responses to manual signals; i.e. deep breath and inspiration. The operation is electric with pneumatic and electronic controls and logic and numerous event indicators and alarms.

Abstract: A volume ventilator effective to give a patient successive inhalations and exhalations at timed intervals is responsive to the patient's effort to inhale and at selected times gives the patient a deep breath synchronized with the patient's effort to inhale.