Pressure actuated flow control valve

Abstract

A pressure actuated flow control valve for an infusion catheter permits gravity flow of a liquid through the catheter and into a patient while resisting back flow of blood from the patient and into the catheter. The valve has a hemispherical body with an outstanding circumferential flange and a normally closed, diametric slit. The slit is longer on the convex outer surface than on the concave inner surface. Dome thickness diminishes in the area adjacent the slit, reducing total apical deflection upon collapse of the slit toward the concave surface. An inner orthogonal rib biases the slit closed. Upon application of a predetermined pressure, the slit opens toward the concave surface to permit forward fluid flow. At lower pressures, the slit closes to check fluid flow. Greater reverse pressure is required to collapse the slit toward the concave surface to permit reverse fluid flow.

Description

RELATED APPLICATION [0001] This is a continuation of application Ser. No. 10 / 304,833 filed Nov. 26, 2002, which is hereby incorporated in its entirety by reference herein.BACKGROUND OF THE INVENTION [0002] The present invention is broadly concerned with a control valve for a medical fluid infusion device. More particularly, it is concerned with a positive pressure actuated flow control valve that permits flow of a liquid from a reservoir, through a cannula and into a patient, while resisting reflux. [0003] Medical infusion therapy employs peripheral and central intravascular devices such as venous and arterial catheters as well as peripherally inserted central venous catheters to deliver fluids, blood products, and pharmaceuticals, including antibiotics and biologics as well as parenteral nutrition. Intravascular devices may also be coupled with pressure monitoring systems. [0004] Regardless of the location of the insertion site of the catheter or the placement of its terminus, intr...

AI Technical Summary

Benefits of technology

[0015] The present invention is directed to a pressure actuated flow control valve for an infusion catheter which permits gravity flow of a liquid through the catheter and into a patient while resisting back flow of blood from the patient and into the catheter. The valve includes a hemispherical dome-shaped body having concave inner and convex outer surfaces. A normally closed, slit communicates between the surfaces. The slit is configured so that it is longer on the convex outer surface than on the concave inner surface. The cross-sectional thickness of the dome diminishes in the area adjacent the slit, reducing total apical deflection upon collapse of the slit toward the concave surface. The dome inner surface includes an orthogonal rib that biases the wall of the dome adjacent the slit to a closed position. Upon application of a predetermined pressure, the slit opens toward the convex surface for facilitating fluid flow in the intended direction. At lower pressures, the slit resumes a closed position to check fluid flow. Relatively greater reverse pressure is required to collapse the slit toward the concave surface to permit reverse fluid flow. The valve includes an outstanding circumferential flange for engagement within a housing.

Problems solved by technology

Partial occlusion results in impaired sampling and fluid administration.

Such infections are associated with increased morbidity and mortality as well as increased health care costs associated with extended hospitalization.

However, PICC devices are not suitable for all applications, particularly where the solution to be administered has high osmolarity or may be a pH irritant.

However, patients may experience bleeding, hydrothorax and subsequent catheter related infections.

However, they have not been found to prevent intravascular device-related infections.

And use of such filters is not regarded as mechanically favorable, since solution filtration may be accomplished more efficiently prior to infusion and the filters themselves are subject to blockage.

There are concerns, however, that they may foster development of resistant bloodstream pathogens.

Needle-free infusion systems also have not yet been fully studied, although one investigation has shown survival of skin flora in needleless infusion systems.

All of the preventive methods that are currently available appear to contribute in some manner to general health care delivery problems, such as delay, increased requirements for nursing care, pharmaceutical and supply costs, increased patient risk and discomfort.

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