Abstract: A medical device with a heat exchanger portion comprising a coiled, corrugated, flattened tube located in a flowpath provided between coaxial cylindrical walls, the tube having a cross sectional configuration including a length smaller in a first direction perpendicular to the axis of the inner and outer walls than in a second direction perpendicular to the first direction.

Abstract: A centrifugal separator comprising a circular centrifuge separation channel having an inlet for receiving a liquid to be separated and an outlet for providing components of the liquid in separated layers at different radial locations, a collection chamber for receiving the separated layers, the chamber having first, second and third outlets in the collection chamber for removing components at different radial locations in the chamber, the first and second collection tubes being joined together so that the combined flow of the two tubes flows in a combined collection tube, and pumps connected to receive liquid streams from the combined collection tube and the third collection tube, the pumps being located externally of, and not rotating with, the channel and collection chamber.

Abstract: Automatically monitoring the volume of blood removed from a patient during the arterial phase of a control cycle of single venipuncture needle apparatus, and switching from the arterial phase to the venous phase when a predetermined stroke volume has been achieved.

Abstract: A fluid flow regulating device comprising a housing defining an inlet, an outlet orifice, and a fluid flow passage therein between the inlet and the outlet orifice, a movable piston in the housing having an upstream surface and a downstream surface exposed to fluid flowing through the passage, means for providing a drop in pressure between the upstream surface and the downstream surface as a function of fluid flow rate through the device, and a closure member that is connected to the movable piston and has an externally curved surface that is movable between positions adjacent to and in front of the outlet orifice as the piston moves in response to changes in the magnitude of the drop in pressure.

Abstract: A peristaltic pump comprising a base, a rotor rotatably mounted about a rotor axis and carrying rollers that travel in a circular path, a race with an internal surface for supporting a flexible tube being squeezed by the rollers traveling in the circular path, the race being pivotally mounted on the base to move between an operating position (adjacent to and concentric with the circular path) and a tube loading position (spaced from the circular path), and means to lock the race in the operating position.

Abstract: A fitting for connecting a helically corrugated heat exchanging tube to a source of heated fluid, the fitting having a plastic tubular member with an end adapted for connection to the source and an end with external helical threads formed on it, the threads being sized to provide a close clearance with the interior surface of the corrugated tube.

Abstract: Blood oxygenating apparatus having a sampling access device connected to the blood outlet port and a blood inlet port of the apparatus by a sample supply line and return line and means to cause the pressure at the blood outlet port to be sufficient to cause a small continuous flow of blood through the lines and access device.

Abstract: Potting the spaced-apart fold edges of a pleated membrane and spacer stack to the interior of a housing without blocking the fluid passages between the spaced-apart pleats by applying a layer of thixotropic adhesive to the fold edges of the pleated membrane and spacer stack and thereafter injecting the potting material between the layer of thixotropic adhesive and the housing.

Abstract: A membrane type blood oxygenator with a microporous membrane separating blood and air channels, the blood in the blood channels flowing downward to cause any accidentally introduced air bubbles to have an increased residence time in the membrane device owing to buoyancy, the blood being at a pressure sufficiently greater than the air pressure to cause passage of air bubbles through the pores of the microporous membrane to the air side prior to being carried out of the device by flowing blood.

Abstract: A tubing injection site guard comprising a compressible, penetrable sleeve for surrounding a continuous tube and a rigid casing enclosing the sleeve. The casing comprises two opposing longitudinal sections longitudinally hinged, with a needle access port in one section to allow insertion of a needle through the sleeve and into the tube. The sections are capable of being locked together to radially compress the sleeve over its entire length and thereby seal needle holes. An adjustable locking means is provided to lock the sections together and to allow adjustment of the radial compression. The site guard also protects the operator from injury while inserting the needle by enclosing the entire injection site except at the needle access port.

Abstract: A cleaning and/or disinfecting system for flushing water and chemical treatment liquids through the hydraulic circuitry of dialysate preparation and supply apparatus, the system employing, for each particular treatment liquid of a plurality of possible liquids, a keyhole adjacent to a chemical intake port and means to send electrical signals to an electrical controller indicating the presence of a key within a particular keyhole, whereby the particular treatment liquid connected to the port is flushed through the hydraulic circuitry of the apparatus at the proper flowrate and for the desired period of time.

Abstract: Measuring the flowrate of a liquid by directing the liquid to a vertically-positioned collection tube, periodically sensing the height of liquid in the tube, and averaging a plurality of data points to obtain an average flowrate value.

Abstract: A system for supplying fluid for a fluid flow transfer device and achieving target ultrafiltration fluid losses by automatically, periodically monitoring the ultrafiltration rate and transmembrane pressure, computing the transmembrane pressure necessary to achieve the target fluid loss by the end of a session, and adjusting the transmembrane pressure to the computed value.

Abstract: Liquid deaeration apparatus having a deaeration chamber, a positive displacement pump downstream of the deaeration chamber, a first flow restrictor upstream of the deaeration chamber, a low pressure sink connected to an air outlet of the deaeration chamber, and a second flow restrictor between the pump and the liquid outlet of the deaeration chamber to raise the pressure at the liquid outlet above that at the air outlet to cause volatilized gas to be removed via the air outlet of the deaeration chamber.

Abstract: Effecting a pressure-tight seal for a fluid-containing housing between surfaces with unmatched contours by providing an elongated opening in the housing along the zone to be sealed and introducing the adhesive through the opening.

Abstract: A fluid flow transfer device having a pleated membrane bonded at its tips to the interior of a housing and a method of making the same wherein a fluid manifold is provided by forming a channel portion in the housing interior, applying a gasket material around the channel portion, and placing the membrane tips against the adhesive to provide a formed-in-place gasket prior to potting of the membrane tips to the housing interior with a potting material.

Abstract: The tips of a pleated membrane are bonded to the interior of the housing of a fluid flow transfer apparatus by positioning support spacers in the membrane folds on the membrane side opposite the side to be bonded, closing the entrances to the spaces between the folds on the bonding side of the membrane, introducing flowable adhesive between the membrane tips and the housing interior while the entrances remain closed, applying a pressure differential across the membrane, with the higher pressure being on the bonding side of the membrane and the differential being large enough to force the membrane folds against their respective support spacers so that the spacers support the membrane, and curing the adhesive to harden it.

Abstract: Making temperature measurements of blood inside a disposable, sterilized medical device by providing receptacles in the walls of the device for receiving temperature-sensitive probes, the receptacles including a tubular heat-conductive member, extending through a wall of the device and being sealed to the wall, and a cylindrical body having protuberances extending radially for cooperating with slots in a temperature-sensitive probe.

Abstract: Diffusing gas into and out of a liquid at a uniform rate by distributing a foam consisting of bubbles with liquid walls surrounding the gas through elongated passages defined by a corrugated surface adjacent to a smooth surface, while simultaneously providing for indirect heat - exchange of the blood foam while the foam is within the elongated passages.

Abstract: Sturdily mounting a disposable medical device by rotatably attaching a back plate to a back brace, biasing the back plate toward the medical device and employing a camming means on the back plate cooperating with a tab on the device to rotate the plate away from the device as the device is initially slid onto the mount and to return the plate to lock the device in place when the device is slid fully onto the mount.