Stop Cock

Abstract

A stop cock comprising a cup-shaped body having three ports and associated spigots formed at right angles to one another, and a plug disposed in the body and sealed thereto above said ports. The plug has a downwardly depending, generally cylindrical wall which defines a recess in the bottom of the plug, the wall being slotted to provide openings alignable with the ports. A stiffening element is inserted in the recess to provide assurance of sufficient radially outward pressure of said walls against the internal surface of said body to seal off said ports when the plug is rotated to a sealing position.

Description

This invention relates to a stop cock or medical valve of the type employed for intravenous injection of drugs and solutions for medical and surgical uses. The present invention provides improved features over the medical valve disclosed in U.S. Pat. No. 3,276,472.

The valve of U. S. Pat. No. 3,276,472 includes a cup-shaped body and a plug rotatably mounted in the body. The cup has three ports and associated spigots by which sources of fluid and a hypodermic needle are attached to the valve with the plug controlling the flow of fluids to the hypodermic needle. The plug has a recess which extends almost to the bottom of the plug and has slots in the side walls of the plug, the slots being alignable with the ports to permit the flow of fluid down through the slots and along the bottom of the body. The deep recess, with its bottom wall extending across the plug, provides a firm sealing engagement of the walls of the plug with the interior surface of the body so as to enable the passage of fluids to be securely blocked when the plug is rotated to a sealing position.

An objective of the present invention has been to provide a valve of the type described above with provision for utilizing the valve for the application of an in-dwelling catheter connected directly to the valve. An in-dwelling catheter consists of a thin tube and a trocar (thin needle) slidable in the tube, the sharpened end of the trocar initially projecting from the end of the tube. In preparing the patient for the in-dwelling catheter, the combined tube and trocar are injected into the vein of the patient with the trocar forming an initial puncture through the skin and vein of the patient, thereby permitting the thin tube to follow the trocar and project into the vein of the patient. Thereafter, the trocar is removed, leaving the thin tube. This system, utilizing a thin tube, has advantages over the use of a hypodermic needle, for a needle, if left in the limb of a patient, could cause injury to the patient through the movement of the patient or valve causing the sharp needle to make inadvertent punctures or scratches on the wall of the vein.

In accordance with the present invention, the thin tube is directly mountable to one of the spigots of the valve and the trocar is adapted to pass through the body of the valve through the thin tube during the time of injecting the catheter into the patient's limb. Thereafter, the trocar is removed and sources of fluid are connected to one or both of the remaining spigots.

It has been another objective of the present invention to provide a plug for a valve of the type described above in which the plug has a downwardly depending, generally cylindrical wall having openings in it alignable with the ports in the body for the passage of fluid. The walls define a deep recess in the body of the plug which permits the passage of a trocar between diametrically opposed ports and through the body and plug.

The need for the deep recess gives rise to a problem of slight radial inward deflection, under applied fluid pressure, of the walls which define the recess. In order to create a suitable sealing relationship between the plug walls and the internal surface of the body, the invention provides a stiffening element located in the bottom of the plug. The stiffening element preferably consists of a disc having an outside diameter equal to that of the inside diameter of the plug recess and a projection extending between the disc and the upper end of the recess to block upward movement of the disc which would tend to occlude the passageway between the opposed ports. The stiffening element further includes means for locating the angular position of the disc with respect to the plug so as to be sure that the projections are out of a line between the opposed ports when the opposed ports are interconnected by the plug.

The several features and objectives of the invention will become more readily apparent from the following detailed description taken in conjunction with the accompanying drawings in which:

FIG. 1 is a diagrammatic perspective view illustrating the application of the invention in an in-dwelling catheter situation;

FIG. 2 is a disassembled perspective view of the invention;

FIG. 3 is a cross-sectional view through the center of the invention;

FIG. 4 is a cross-sectional view taken along lines 4--4 of FIG. 3; and

FIGS. 5, 6 and 7 are plan views of alternative forms of stiffening elements .

Referring to FIG. 1, a stop cock 10 is shown interconnecting a thin catheter tube 11 to a hypodermic syringe 12 and a tube 13 connected to a source 14 of an intravenous solution such as glucose.

Referring to FIGS. 2, 3 and 4, the valve 10 includes a body 16, a plug 17 rotatably mounted in the body, and a stiffening element 18. The body is cup-shaped and has three ports 20, 21 and 22 and spigots 23, 24 and 25 associated with respective ports.

The body has an internal surface 26 which is generally cylindrical and mates with, in a tight fitting relation, a cylindrical surface 27 of the plug 17. The upper end of the surface 26 of the body has an annular groove 28 which receives a sealing ring 29 at the upper end of the surface 27 of the plug.

The plug has a generally cylindrical, downwardly depending wall 31 defining a recess 32 having an upper end 33. The wall 31 has three slots 35, 36 and 37 which are alignable with respective ports 20, 21 and 22 to permit communication of the ports with each other for the flow of fluid.

The plug further includes a handle 40 and pointers 41 all located exteriorly of the body. The pointers 41 are aligned with the respective slots 35-37 to indicate the angular position of the slots in relation to the spigots, thereby advising the operator of the condition of the valve insofar as sealing off ports and interconnection of ports is concerned.

The stiffening element includes a disc 45 and four projections 46 which extend between the disc and the upper end 33 of the recess, thereby locating the disc at the open end of the recess. The disc has two laterally projecting tabs 47 which are slidably received in the opposed slots 35 and 37, locating angularly located the disc in the recess. The angular locating of the disc in the recess provides assurance that the projections 46 will be out of line with the ports 20 and 21 when the plug is rotated to bring those ports into communication with one another, as shown, for example, in FIG. 4.

The particular configuration of the stiffening element 18 is subject to variation without departing from the invention. For example, a stiffening element 50 is shown in FIG. 5 which consists of a generally cylindrical member whose height is substantially equal to the depth of the recess 32, the element having a T-shaped slot 51 which defines the projections and which permits the required flow of fluid and passageway for the introduction of a trocar.

A similarly formed stiffening element 53 is shown in FIG. 6, the element 53 having a cruciform slot 54 which defines the projections.

The stiffening element 56 of FIG. 7 is employed in an application where there is no requirement for the introduction of a trocar. The element 56 has a disc 57 and a simple centrally located projection 58 extending between the disc 57 and the upper end of the recess 32. No locating tabs are required in the embodiment of FIG. 7.

In the use of the invention of the embodiments of FIGS. 1-6, the medical valve with a thin tube 11 attached to it and a trocar extending through the valve with its tip projecting from the end of the thin tube is placed on the patient's arm. Preferably, the plug is rotated to the orientation illustrated in FIG. 4 wherein the port 22 is sealed off and the ports 20, 21 are interconnected so as to permit the trocar to pass through the valve. Further, it is preferable to have the spigot 24 opposite the spigot 23 carrying the thin tube preliminarily sealed off by a cap of the type normally closing a bottle of fluid from which the doctor fills a hypodermic syringe. Such a cap is puncturable by the trocar and reseals itself when the trocar is removed to prevent the escape of blood from the valve during the period between the removal of the trocar and the rotation of the plug to a sealing orientation.

The trocar and tube are introduced into the patient's vein and the trocar is thereafter removed. The valve is rotated about one-eighth of a turn to seal all ports. The sources of respective fluids are then connected to the remaining spigots 24 and 25, after first removing the cap from the spigot 24. Thereafter the plug is rotated to align the desired ports 21 and 22 with the port 20 or to seal off the ports as required.

In the operation, the stiffening element 18 braces the wall 31 against radial inward movement, thereby providing assurance of good sealing engagement of the wall with the internal surface 26 of the body 16. Additionally, the element 18 minimizes the residual fluid of one source in the body 16 when the valve is changed to connect another source to the tube 11.

Claims

I claim:

1. A medical valve comprising,

a generally cylindrical cup-shaped body having at least two diametrically opposed ports in the lower portion thereof,

a plug rotatably mounted in said body,

cooperating means on said plug and body respectively for forming a liquid-tight seal above said ports,

the lower portion of said plug being formed by a generally cylindrical wall which defines a recess extending above said port locations,

said wall having openings alignable with said ports to permit liquid to pass through said valve,

and a stiffening element snugly fitting in said recess below said port locations to provide radially outward pressure of said wall against said body to seal said ports.

2. A valve as in claim 1 in which said stiffening element comprises a disc disposed at the bottom of said plug,

and at least one projection extending between said disc and the upper end of said recess.

3. A valve as in claim 1 further comprising,

positioning means extending between said stiffening element and the upper end of said recess, said positioning means being out of a line between said openings in said plug walls.

4. A valve as in claim 3 in which the openings in said valve are formed by slots extending from the bottom of said plug to the top of said ports.

5. A valve as in claim 4 in which said stiffening element has at least one laterally projecting locator tab disposed in at least one of said slots to block rotation of said element with respect to said plug.