Abstract: The invention is a pressure sensitive valve that in different forms can be used to provide: an adjustable resistance to flow, adjustable positive or negative pressure relief, negative pressure isolation, isolation of pressure sensitive devices (e.g. pressure monitors) from blood and controlled recirculation between the inlet and outlet of pumps, particularly extracorporeal circulation. The construction of the valve is especially advantageous for extracorporeal circuits, the valve is made from one continuous length of tubing, thereby providing a valve that is more reliable, safer, and has fewer parts. A simple, compact and disposable system to adjust, regulate, and indicate negative or positive pressure applied to the valve is so described.

Abstract: The invention is a pressure sensitive valve that in different forms can be used to provide: an adjustable resistance to flow, adjustable positive or negative pressure relief, negative pressure isolation, isolation of pressure sensitive devices (e.g. pressure monitors) from blood and controlled recirculation between the inlet and outlet of pumps, particularly extracorporeal circulation. The construction of the valve is especially advantageous for extracorporeal circuits because the valve is made from one continuous length of tubing, thereby providing a valve that is more reliable, safer, and has fewer parts. A simple, compact and disposable system to adjust, regulate, and indicate negative or positive pressure applied to the valve is also described.

Abstract: The invention is a pumping system composed of a relatively thin wall extruded tubing that in different forms can provide flow regulation for peristaltic pumps, reduce spallation, extend pumping life, provide means to measure inlet and outlet pressure of the peristaltic pump and limits the inlet and outlet pressure generated by peristaltic pumps, and a special peristaltic pump that takes advantage of the characteristics of the aforementioned tubing. The invention has particular usefulness in the medical industry for pumping physiological or nutritional liquids.

Abstract: The invention is a pressure sensitive valve that in different forms can be used to provide: an adjustable resistance to flow, adjustable positive or negative pressure relief, negative pressure isolation, isolation of pressure sensitive devices (e.g. pressure monitors) from blood and controlled recirculation between the inlet and outlet of pumps, particularly extracorporeal circulation. The construction of the valve is especially advantageous for extracorporeal circuits because the valve is made from one continuous length of tubing, thereby providing a value that is more reliable, safer, and has fewer parts. A simple, compact and disposable system to adjust, regulate, and indicate negative or positive pressure applied to the valve is also described.

Abstract: The specification discloses a disposable low-cost constant pressure infusion pump intended to be used with an infusion cuff, or other infusion device for the infusion of sterile physiological solutions into the human body. The device utilizes an enclosure, which may be an infusion cuff or a pressurizing chamber that is adapted to receive a disposable bag of physiological solutions therewithin. A pressurizing chamber is formed about and around the bag of physiological solution, to define a pressure chamber to which is supplied a regulated pressure. The regulated pressure is provided from a small low-cost disposable canister of freon or other pressurizing fluid through a pressure regulating mechanism. The canister is equipped with a springloaded discharge valve, and the pressure regulating mechanism balances the spring constant of this discharge valve against an elastic wall or other resilient diaphragm to balance the loading between the elastic wall and springloaded discharge valve.

Abstract: The present invention provides a pumping chamber to be constructed as follows:A collapsible tubing is attached to an inlet fitting and to and outlet fitting to transport a biologic fluid such as blood therethrough. An outer tubing surrounds the collapsible tubing and is secured to the outer surface of the inlet fitting and to the outer surface of the outlet fitting, forming a chamber thereby. At least a duality of ports defining passageways through the wall of the outer tubing permits communication of the chamber with ambient conditions outside the chamber. The ports are designed to accept such devices as pressure gauges, alarm systems and devices to regulate intrachamber pressure, to observe arterial pressure, and to regulate collapse and occlusion of collapsible tubing in response to inadequate blood volumes.

Abstract: A continuous length of flexible polymeric tubing having a smooth fissureless inner surface throughout is provided with a region intermediate its ends which region has an inside diameter greater than the inside diameter of the remainder of said tubing and a thinner wall than that of the remainder of said tubing with a gradual transition in wall thickness and diameter therebetween. A rigid walled enclosure surrounds said region of the tubing with a slight clearance therebetween except at the ends of the enclosure which encircle the tubing beyond said region with a snug fit. A duct is joined to the enclosure near one end for feeding fluid under pressure thereto. Various arrangements of over-pressure relief prevent pinching of the tubing while affording controlled indentation thereof. The transition section of the tubing wall can cooperate with a port in the enclosure to afford said overpressure relief. Portions of the tubing wall may be thickened (i.e.