Abstract: A blood pump provides a mechanism to prevent excessive growth of tissue at the transition zone between a smooth blood contacting surface and a textured blood contacting surface. The blood pump includes a blood flow channel having a textured surface, a smooth surface adjacent to the textured surface, and a rotor positioned within the blood flow channel. The rotor includes at least one impeller blade that defines a sweep when the rotor turns. The impeller blade is designed to cut off a portion of a biologic lining as it grows from the textured surface into the sweep of the impeller blade.

Abstract: Disclosed is a percutaneous access device (PAD) for long-term skin penetration and use as an access port in the body of a patient. The buttonlike device includes a flat skirt for subdermal anchoring of the PAD and a neck through which a tube may extend for transmission of materials to or from the body. A two-stage porous bed covering the skirt and at least a portion of the neck promotes formation of a tight, infection-free barrier between the percutaneous access device and adjacent tissues, stabilizing the device for long-term use. The first stage of the bed retards downgrowth of epidermal cells for a time sufficient for mature collagen to form in the second stage, thereby permitting the tight dermal/biomaterial interface or barrier to form at a location near the junction of the two stages.

Abstract: Disclosed is an improved peritoneal access system for providing repeated, long term access through the peritoneum, as for patients undergoing peritoneal dialysis. The system includes a catheter tube extending through an implantable percutaneous access device (PAD) formed of a cylindrical neck and a buttonlike annular skirt. A portion of the catheter tube external to the PAD has a bellows integrally formed therein permitting the tube to be bent and moved without restricting fluid flow or stressing the PAD. The internal portion of the catheter tube has a sharp right angle below the PAD to tunnel the tube in a subcutaneous plane to the peritoneal penetration site and a position-adjustable collar for anchoring/sealing the cathether tube near the upper surface of the peritoneum.

Abstract: Disclosed is a percutaneous access device (PAD) with a connector lock which facilitates replacement and removal of tubes transmitting materials to or from the body of a patient without the need for surgery and with minimal interference with an implanted PAD. The lock may include a screw ring and elastomeric seal attachable to the neck of the device through which a tube extends, and the neck has recesses in its outer surface to permit it to be tightly restrained during tightening or loosening of the lock. A flat skirt or flange provides subdermal anchoring of the buttonlike percutaneous access device, and a two-stage porous bed covering portions of the neck and skirt promotes formation of a tight dermal/biomaterial barrier near the junction of the two stages of the porous bed.

Abstract: An inhalation device for use in breathing exercises is described. The exerciser includes a thin-walled bellows whose upper end is attached to a top housing member and whose lower end deflects upward upon withdrawal of air from an opening in the upper end of the bellows. Deflection of the bellows allows accurate measurement of the volume of air inhaled by a patient and a true indication whether an inhaled breath is being held. Slotted support arms connecting the top housing member and a bottom housing member permit collapse of the device for storage and shipment of the exerciser as a compact unit. A weight attached to the lower end of the bellows provides a biasing force to assure return of the bellows to a fully extended position even after long-term storage of the device in collapsed form.

Abstract: An inhalation device for use in respiratory therapy is described. The inhalation device or incentive breathing exerciser includes an inner bellows whose deflection allows accurate measurement of the initial volume of air inhaled by a patient and an outer bellows for measuring larger volumes of air after a valve in the inner bellows opens. The exerciser permits measurement of the true volume of air inhaled by a patient and is equipped with a simple timer for measuring the interval of time an inhaled breath is held. Removable handles and the flexible bellows permit collapse of the device for storage and shipment as a compact unit.

Abstract: Apparatus is disclosed for mechanically assisting circulation of blood in a patient for periods of up to a week or two until the patient's heart strengthens sufficiently to take over the full workload. The circulatory assist device includes a valveless pump with a flexible bladder, a pneumatic driver for applying pressure pulses to the bladder, and a single flexible conduit for conveying blood between the patient and the pump. In use the pump and driver are mounted external to the patient's body and the flexible conduit is connected to the pump and in end-to-side relationship with a major blood vessel on that side of the heart, either right or left, which is in need of support.

Abstract: A pneumatic pump adapted primarily as a left ventricular heart assist device includes a flexible bladder with a rigid housing. A pneumatic driver applies rhythmical pulses between the bladder and the housing to repetitively collapse the bladder and establish a pumping action through the bladder, in conjunction with check valves in the inlet and outlet to the bladder. Between the driver and the pump there is provided a pneumatic pulse limiter which includes a flexible diaphragm isolating the driver from the pump. Pulses from the driver are transmitted to the pump only through the flexible diaphragm and the diaphragm is constrained to move only within established limits. Regardless of the magnitude of the pulse from the driver, the maximum pulse applied to the pump cannot exceed that corresponding to the maximum displacement of the diaphragm.Between successive pulses, the portion of the system between the driver and the flexible diaphragm is depressurized.

Abstract: A compact blood pump includes a flexible bladder mounted within a rigid metal housing. Pneumatic pulses between the bladder and the housing produce pumping action in association with appropriate inlet and outlet valves. The bladder is configured to provide a stiffness characteristic which produces a recurring three lobe collapse pattern during pumping operation. Inlet and outlet passages to the bladder are associated with detachable seal rotatable fluid conduits in fluid-tight relationship to the bladder. The conduits are attachable and rotatable without transmitting torque to the flexible bladder.

Abstract: An artificial blood conduit comprises two concentrically associated tubes. Convolutions in the tube walls provide flexibility and reduce the tendency to kink. The inner tube is porous to promote the growth of a stable biological interface. The outer tube is impervious to prevent contamination of the blood in locations external to the host body. Rigid reinforcing rings located between the two tubes and affixed to the outer tube, provide the conduit with strength to resist collapse from a wide variety of stress forces. A Dacron cloth sewn tightly around the exterior of the conduit allows tissue fixation without puncturing the conduit. End connectors are provided for different types of anastomoses.

Abstract: Blood-contacting surfaces of artificial implant devices which have been flocked with fibers of a blood-compatible polymeric material to promote formation of a stable and viable biological lining when the device has been implanted in a living body, are treated to strengthen the bonds between the fibers and the substrate surface and to interlock the fibers with each other so as to substantially reduce the possibility of fiber separation and release from the substrate surface into the blood stream. The treatment is effected by applying to the flocked surface a dilute solution of an adhesive material in a solvent therefor, the content of the adhesive material in the treating solution being controlled so as to be sufficient to coat the fibers only at their points of contact with each other and with the substrate surface.

Abstract: A pneumatic pump adapted primarily as a left ventricular heart assist device includes a flexible bladder with a rigid housing. A pneumatic driver applies rhythmical pulses between the bladder and the housing to repetitively collapse the bladder and establish a pumping action through the bladder, in conjunction with check valves in the inlet and outlet to the bladder. Between the driver and the pump there is provided a pneumatic pulse limiter which includes a flexible diaphragm isolating the driver from the pump. Pulses from the driver are transmitted to the pump only through the flexible diaphragm and the diaphragm is constrained to move only within established limits. Regardless of the magnitude of the pulse from the driver, the maximum pulse applied to the pump cannot exceed that corresponding to the maximum displacement of the diaphragm.Between successive pulses, the portion of the system between the driver and the flexible diaphragm is depressurized.

Abstract: Blood-contacting surfaces of artificial implant devices which have been flocked with fibers of a blood-compatible polymeric material to promote formation of a stable and viable biological lining when the device has been implanted in a living body, are treated to strengthen the bonds between the fibers and the substrate surface and to interlock the fibers with each other so as to substantially reduce the possibility of fiber separation and release from the substrate surface into the blood stream. The treatment is effected by applying to the flocked surface a dilute solution of an adhesive material in a solvent therefor, the content of the adhesive material in the treating solution being controlled so as to be sufficient to coat the fibers only at their points of contact with each other and with the substrate surface.