Infusion check valve for medical devices

An intravascular valve assembly having a valve case and a flexible pressure-actuated flow control valve. The valve case includes attached proximal and distal case portions that present respective spaced apart fluid ports and a fluid passageway extending between the ports. The flexible pressure-actuated flow control valve is disposed within the fluid passageway and includes a slitted central valve wall. The proximal case portion includes an axially-extending boss that projects distally, with a portion of a distal end of the boss contacting the flow control valve. The valve permits fluid flowing in a distal direction to pass through the slit. Fluid flowing in a proximal direction, however, causes the valve to compresses against the boss and the slit to close, thus restricting fluid flow in a proximal direction.

BACKGROUND

The present invention relates generally to infusion devices used for the administration of various fluids and medications to patients. More specifically, embodiments of the present invention are directed to an infusion check valve assembly for an intravenous catheter.

2. Related Art

The use of intravenous devices for the administration of parenteral and other fluids to patients is a common practice. A variety of devices for such purposes have been proposed in the past, such as a simple length of tubing having a fitting on one end for making connection with a source of fluid (e.g., a bottle or flexible bag), while the other end is provided with a needle or catheter that may be inserted into the vein of a patient. A persistent problem with prior infusion devices is referred to as fluid reflux, or the tendency for fluids, such as blood or medication, to be drawn into the infusion apparatus. Fluid reflux can occur in prior art devices, for example, when a gravity supply fluid source is empty, when medication is infused through an adjacent component, or when a cannula is removed from a septum or port.

Prior art pressure-activated infusion devices that reduce fluid reflux using a flexible valve are problematic due to design and manufacture-related issues. Flexible valves may often times mechanically invert within the internal passage of the valve housing due to elevated back pressure. Upon such an inversion, the flexible valves may be forced into a permanently open position, thus permitting blood or other unwanted fluids and medication to reflux back through the valve. Prior art check valves, such as certain types of disc valves, used to reduce or restrict fluid reflux typically require high cracking pressures for incoming fluids to open and pass through the valves. In certain applications, high cracking pressures may be acceptable. However, in other applications, lower cracking pressures may be necessary. To reduce the cracking pressures in prior art check valves, the valves are often designed with large diameters, such that the valves present enough surface area to reduce the cracking pressures to acceptable levels. Although such prior art check valves may assist in reducing fluid reflux, because of the increased size of the valves, they may be inefficient, and often times impractical, for the intravenous administering of fluid and medication.

There is accordingly a need in the art for improved intravascular devices equipped with a check valve component that eliminates the possibility of fluid reflux, while providing for the efficient administration of medical fluids.

SUMMARY

Embodiments of the present invention are directed to an intravascular check valve assembly that restricts fluid reflux in a proximal direction, while maintaining a low cracking pressure for fluids to be introduced through the assembly in a distal direction.

An aspect of the present invention concerns an intravascular check valve assembly that controls fluid flow in distal and proximal directions. The assembly broadly includes a valve case and a flexible pressure-actuated flow control valve. The valve case includes attached proximal and distal case portions, with the distal case portion positioned closer to a patient when the device is in use and a proximal case portion opposite and extending away from the distal case portion. The case portions present respective spaced apart fluid ports and a fluid passageway extending between the ports. The flexible pressure-actuated flow control valve is disposed along the fluid passageway to control fluid flow therethrough. The valve includes a central valve wall having at least one slit at a distal end of the wall, with the wall presenting distal-facing and proximal-facing surfaces. The proximal case portion of the valve case includes an axially-extending boss that distally projects from the proximal case. The boss includes a portion of a distal end that engages at least a portion of the proximal-facing surface of the flow control valve. The boss includes one or more channels positioned adjacent to a radial-most edge of the boss, such that the channels fluidly connect the fluid port of the proximal case to the proximal-facing surface of the flow control valve. The valve wall flexes to open the at least one slit in response to a fluid flowing in a distal direction through the channels of the boss and through the valve. The valve wall compresses against the boss and closes the slit in response to a fluid flowing in a proximal direction, thereby preventing fluid flow through the valve assembly in the proximal direction.

Other aspects and advantages of the present invention will be apparent from the following detailed description of the embodiments and the accompanying drawing figures.

The drawing figures do not limit the present invention to the specific embodiments disclosed and described herein. The drawings are not necessarily to scale, emphasis instead being placed on clearly illustrating the principles of the invention.

DETAILED DESCRIPTION

Beginning withFIGS. 1-3, a valve assembly12is generally comprised of a luer lock fitting14positioned on a distal end of the valve assembly, and a valve support16attached to a proximal end of the luer lock fitting14and operable to receive a flexible pressure-actuated flow control valve18. The valve assembly12may be installed in line between a peripheral catheter20positioned on the distal end of the luer lock fitting14and a support body22removably connected to a proximal end of the valve support16. Although the valve assembly is shown with the peripheral catheter20and support body22, it will be appreciated that the valve assembly can be used in other applications. For example, the valve assembly12could be used with a central venous catheter (CVC), another intravascular catheter, or a needle. Furthermore, the valve assembly could be used with other types of connection components, tubing, etc. As used herein, the terms “distal” and “proximal” refer, respectively, to directions toward and away from a patient.

In more detail, the illustrated peripheral catheter20is itself entirely conventional and includes an annular proximal base26with diametrically opposed connection tabs28for threaded connection to the luer lock fitting14. The catheter20also includes a distally extending barrel30and cannula32secured to the distal end of the barrel30. As is customary, the cannula32is inserted into a patient so that medicaments can be injected via the valve assembly12. As previously mentioned, the principles of the present invention are equally applicable to other catheter designs, as well as other components permanently or removably secured to the valve assembly.

The support body22has a generally cylindrical overall shape and may be a unitary body molded from a thermoplastic, synthetic resin, or the like. The support body22includes a distal annular inner barrel36, and a distal annular outer connection wall38. The outer connection wall38includes a threaded interior surface40and an exterior surface42that is swaged or flanged to facilitate gripping. The support body22is otherwise hollow at its distal end, such that it can receive the valve support16, which may be secured to the support body22between the inner barrel36and the threaded interior surface40. The proximal end of the support body22is axially apertured to permit coupling with a supply tube44having an outer surface and an inner surface defining a lumen46. The inner barrel36presents a fluid passageway48athat is fluidly connected with the lumen46. The proximal end of the support body22is equipped with a molded fitment50to accommodate the supply tube44. The proximal end of the supply tube44is coupled with a fluid reservoir (not shown) so that the lumen46is in fluidic communication with the reservoir.

Although not shown inFIGS. 1-3, the support body22may also be equipped with a stopcock or a plurality of infusion ports with plugs for receiving a syringe and/or needle. A pump may be installed in line with the supply tube44, which may also be equipped with clamps (neither is shown).

The catheter20and supply tube44are flexible and pliant to facilitate placement and usage and to minimize both mechanical insult to the blood vessels and patient discomfort during long-term use. They may be constructed of any suitable medical grade material, such as, for example, polyethylene, polyvinyl chloride, Teflon, silicone elastomer or polyurethane or mixtures thereof. The material may be coated or impregnated with an antimicrobial or antiseptic composition to reduce bacterial adherence and biofilm formation. The catheter20may also be constructed of a radiopaque material in order to facilitate imaging for locating any breaks and/or separated sections.

The valve support16serves to support and interconnect the support body22and luer lock fitting14. The valve support16preferably comprises a molded synthetic resin rigid body that includes a hub56and a cup-like structure that includes a valve seat58, a sidewall60, and an axially-extending boss62that projects distally from the valve seat58. The hub56has a hollow, cylindrical configuration, including a proximal neck64with a fluid passageway48b. The neck64includes a series of luer lock threads68designed for mating engagement with corresponding standard luer threads in the support body22. Alternately, a conventional threaded or bayonet-type fitting may be substituted in the neck64and support body for the luer fittings shown and described. The fluid passageway48bextends through the hub and the mid-section and is operable to receive the inner barrel36from the support body22. Certain embodiments may provide for the passageway48bto have a diameter that ranges from about 0.070 inches to about 0.125 inches. The passageway48bserves as the fluid connection between the inner barrel36and the cup-like structure that holds the flow control valve18. However, it is also within the scope of the present invention to have additional or alternative structure provided to interconnect the cup-like structure and the hub.

Remaining withFIGS. 1-3, the cup-like structure is configured to hold the flow control valve18, as will be discussed further. The valve seat58comprises a radially-extending wall attached to the distal end of the hub56and presents a proximal flange-engaging face72. The sidewall60comprises an annular wall that presents interior, annular, proximal and distal axial surfaces74,76that are joined by a shoulder78. The sidewall60extends endlessly about the valve seat58and is preferably integrally formed with the valve seat.

As best illustrated inFIGS. 3-5, the axially-extending boss62projects distally from the valve seat58and, in certain embodiments, presents a distal-facing surface80. The boss62includes a proximal base that presents a proximally-facing radial surface82extending across an entire radial width of the fluid passageway48b. In certain embodiments, such as illustrated inFIG. 3, the distal-facing surface80may be arcuate-shaped. In other embodiments, the distal-facing surface80may be substantially arcuate-shaped, such as hemispherical or parabolical. In still other embodiments, the distal-facing surface80may include various other shapes, such as conical, cylindrical, rectangular, square, or the like. In even further embodiments, the boss62may be complementary-shaped with a shape of at least portions of the valve18, as will be discussed in more detail below. The following descriptions of the relative positioning between the valve18and boss62are applicable when the valve is in a natural or an at rest state (i.e., fluid is not flowing in either a proximal or distal direction through the valve assembly12). As illustrated inFIG. 3, the boss extends axially, such that at least a portion of a distal end84of the boss62may contact at least a portion of the valve18, with the distal end84generally comprising the distal most axial one-third of the boss62. In certain embodiments, a distal most portion of the distal end84, including an apex of the boss64, contacts a portion of the valve18. However, in other embodiments, portions of the distal end84other than the distal most portion may contact the valve18. In even further embodiments, the boss62may not contact the valve18but may be separated from the valve by at least some nominal distance. Embodiments of the present invention contemplate various contact and separation arrangements between the boss62and the valve18, so long as the boss62and valve18are operable to restrict the flow of fluid in a proximal direction, as will be discussed in more detail below.

In further embodiments, the distal end84of the boss62may include a distal facing flat surface86(seeFIGS. 6-7) comprising a plurality of points each lying within a plane that extends entirely radially with respect to the valve assembly12. In such an embodiment and as illustrated inFIG. 7, the flat surface86may contact at least a portion of the valve18. However, as described above, embodiments of the present invention include various contact and separation arrangements between the boss62and the valve18, so long as the boss62and valve18are operable to restrict the flow of fluid in a proximal direction, as will be discussed in more detail below.

Returning now toFIGS. 3-5, the boss62is generally solid; however, the boss includes at least one generally axial directed channel88that provides a flow through opening, such that the channel88fluidly communicates with the fluid passageway48b. The at least one channel is generally positioned axially through the boss62, presenting a proximal opening in the proximally-facing radial surface82and a distal opening in the distal-facing surface80. Because the distal opening of the channel is presented in the distal-facing surface80of the boss62, the distal opening is presented in the form of a cutout on the surface of the boss. In certain embodiments, the at least one channel88is positioned such that the proximal opening of the channel is adjacent to a radial edge of the boss62. In additional embodiments, the channel88may be positioned further within an interior of the boss62, such that the proximal opening of the channel is a non-nominal distance from the radial edge of the boss.

Embodiments of the present invention provide for the channel88to be cylindrical, such that the cutout in the distal-facing surface80is generally elliptical in shape along its longitudinal axis. In such an embodiment, a proximal most width of the channel is of generally the same size as a distal most width of the channel. In other embodiments, the channel may be teardrop-shaped, such that the cutout is generally shaped in the form of a tear drop or a cone along its longitudinal axis. In such an embodiment, a proximal most width of the channel is wider than a distal most width. The above-mentioned cutout shapes are provided for exemplary purposes only and are non-limiting. For instance, the cutouts may be in the shape of ovals, triangles, or the like. Embodiments of the present invention contemplate the use of one or more channels presenting cutouts of any shape that may facilitate the flow of fluid through the valve assembly12. Variations of the cutout shape may be required based on specific requirements for a particular fluid and/or drug delivery, such as flow rates or viscosity characteristics. In addition, embodiments of the present invention may provide for more than one channel88to be included within the boss62, as will be described in more detail below.

As best illustrated inFIG. 3, the luer lock fitting14is preferably a unitary fitting molded from a thermoplastic material, a synthetic resin, or the like. The fitting14includes a proximal annular valve cover92, a distal annular inner barrel94, and a distal annular outer connection wall96. The fitting14also presents a proximal connection end98with proximal and distal axial surfaces100,102, and proximal and distal shoulders104,106and is designed to be received by the distal socket of the valve support16. The connection end98is designed to mate with the sidewall60so that respective surfaces74,100, shoulders78,104, and surfaces76,102engage one another to interconnect the fitting14and the valve support16and to secure the flow control valve18, as will be discussed further. The annular base26of peripheral catheter20is threaded into the fitting14, between the inner barrel94and outer connection wall96. The fitting14also presents fluid passageway48cthat extends through the inner barrel94and valve cover92. While the fitting14may be configured as a luer lock fitting, the principles of the present invention are equally applicable where fitting14includes a different type of connector for attachment to the catheter20(or for attachment to other infusion/aspiration set components such as a needle or tubing).

The valve cover92also presents a distal annular flange-engaging face110spaced radially between the proximal surface100and the passageway48c, with the distal face110preferably including an endless annular groove112for receiving and holding the flow control valve18precisely between the valve support16and fitting14. However, it is also within the scope of the present invention where the valve seat58is alternatively configured to receive the flow control valve18, as will be discussed further.

Turning toFIG. 8, the flow control valve18is configured to selectively permit distal and proximal fluid flow through the valve assembly12and includes a peripheral flange116and a central body118surrounded by the flange116. The body118and flange116are integrally formed from resilient silicone, but could include another synthetic resin material. In certain embodiments, the central body118may be arcuate-shaped, such as is illustrated inFIG. 8. In additional embodiments, the central body118may be substantially arcuate-shaped, such as hemispherical or parabolical. In still other embodiments, the central body118may include various other shapes, such as conical, cylindrical, rectangular, square, or the like. In even further embodiments, the central body118of the valve18may be complementary-shaped with a shape of at least portions of the boss62. The body118comprises a wall120that may present proximal-facing and distal-facing surfaces120a,120b. In embodiments where the body118is arcuate-shaped, surfaces120a,120bmay be concave and convex, respectively. The wall120also includes a distal end, and a thickness of the wall decreases progressively to the distal end of the wall. The body118also includes a rib122extending along the proximal-facing surface120aof the wall120. Yet further, the body118presents opposed interior valve edges124that extend perpendicularly relative to the rib122and extend axially through the body118to define a slit126. In additional embodiments of the present invention, the edges124may extend inline, or parallel, relative to the rib122such that the slit126is similarly inline, or parallel, to the rib. In further embodiments, the body118may include a plurality of slits126that extend therethrough.

Embodiments of the present invention also provide for the slit126, defined by the edges124, to vary in length depending on a cracking pressure required for specific applications. In typical configurations, the slit126extends in opposite directions from the distal end of the valve18down the body118to approximately midway between the distal end and the flange116. However, in applications that require a lower cracking pressure, such as an inline check valve system discussed in more detail below, the slit126may be relatively longer and extend down the body118further than approximately midway between the distal end and the flange116. Such low cracking pressures may facilitate, for instance, the infusion of fluids and/or medications from fluid bags, drip chambers, or the like. Alternatively, in applications that require a higher cracking pressure, such as in Y-site check valve and manifold check valve systems discussed in more detail below, the slit126may be relatively shorter and extend down the body118less than approximately midway between the distal end and the flange116. Such high cracking pressures may be appropriate, for instance, for the administration of fluids and/or medications from syringes or other injection devices. Regardless of whether the length of the slit126provides for a higher or a lower cracking pressure, embodiments of the present invention function to restrict fluid from flowing proximally through the valve assembly12. Additional features of the body118are disclosed in U.S. Pat. No. 7,967,797, issued Jun. 8, 2011, entitled INTRAVASCULAR VALVE COMPONENT WITH IMPROVED VALVE POSITIONING, and U.S. Pat. No. 7,959,614, issued Jun. 14, 2011, entitled PRESSURE ACTUATED FLOW CONTROL VALVE, both of which are hereby incorporated by reference in their entirety.

The flange116includes an endless annular flange wall128surrounding and attached to the body118(seeFIG. 8). The flange116also includes an endless annular valve-seating projection130extending distally from the flange wall128and spaced radially between an outermost edge132of the flange wall128and the body118. Preferably, the projection130is spaced radially outwardly from the body118to permit the edges124to flex between open and closed configurations, as will be discussed. Embodiments of the present invention are also applicable where the projection130is alternatively configured to provide a mechanism for precisely seating the flow control valve18within the valve assembly12(seeFIG. 3). For instance, the projection could extend proximally from the flange wall128. Furthermore, multiple projections130could extend distally and/or proximally from the flange wall128to secure the flow control valve18. For example, the projection130could comprise multiple arcuate segments that are spaced circumferentially from one another and cooperatively extend about the body118. Alternatively, the projection130could include multiple radially-spaced segments.

The flow control valve18is assembled between the valve support16and fitting14by positioning the valve18on valve seat58. In particular, the distal end of the wall120of the valve18is inserted into a proximal end of the passageway48c, and the projection130is inserted into the annular groove112. The projection130and groove112are preferably shaped to guide the flow control valve18into axial alignment with the fitting14. Preferably, the groove112and projection130are complementally shaped so that the projection130fits snugly within the groove112and the flow control valve18is coaxially aligned with the fitting14(thereby positioning the central body118concentrically within the passageway48c). In this manner, the interengagement between the groove112and projection130restricts relative radial movement between the flow control valve18, support body22, and fitting14. In addition, the groove112and projection130permit the flow control valve18to be selectively angularly rotated about the valve axis and relative to the support body22and fitting14, although this is likely unnecessary with the illustrated embodiment because of the symmetrical construction of the control valve18.

The following descriptions of the positioning of the valve18are applicable when the valve is in a natural or an at rest state (i.e., fluid is not flowing in either a proximal or distal direction through the valve assembly12). The flow control valve18is positioned onto the valve seat58and over the boss62by locating a proximal surface of the flange wall128against the flange-engaging face72. The valve18is positioned over the boss62, such that at least a portion of the distal end84of the boss62may contact the valve18. In certain embodiments of the present invention, at least a portion of the distal end84contacts at least a portion of the rib122that extends along the proximal-facing surface120aof the valve18. In additional embodiments, and as discussed above, a portion of the distal end84of the boss62may be flat instead of convex (seeFIGS. 6-7). In such an embodiment, at least a portion of the flat surface86of the boss contacts the valve18. And in certain embodiments, at least a portion of the flat surface86of the boss may contact the rib122of the valve18. Although at least a portion of the boss62contacts at least a portion of the valve18, a radial diameter of the boss is generally smaller than a radial diameter of the proximal-facing surface120aof the valve18. Thus, except for the at least a portion of the boss62that contacts the valve18, the remaining surface area of the boss generally does not contact the valve18. Such structure and relative positioning between the boss62and the valve18leaves a space, hereinafter a fluidic chamber134, that collects the fluid and/or medication that is introduced into the valve assembly12as it passes through the one or more channels88of the boss. As fluid builds up in the fluidic chamber134, the fluid creates a pressure that can be used to open the valve slit126to let the fluid through the valve18, as will be discussed in more detail below.

As discussed previously, the fitting14is secured to the valve support16by inserting the connection end98into the distal socket of the valve support. The valve support16and fitting14are further secured by attaching respective adjacent pairs of surfaces using a conventional ultrasonic welding process to form an hermetic seal between the valve support16and fitting14. Embodiments of the present invention are also applicable where the valve support and fitting are alternatively attached to one another, e.g., where the valve support16and fitting14are attached by a snap-fit interengagement or adhered to one another using a suitable adhesive.

With the connection end98inserted, the valve support16and fitting14cooperatively present an internal valve chamber that receives the flow control valve18. The faces72,110engage the flange wall128on corresponding sides and compress the flange wall128into a compressed state so as to firmly hold the valve18within the valve assembly12. More preferably, the valve support16and fitting14are interconnected so that a thickness dimension T (seeFIG. 8) of the flange wall128is axially compressed from an uncompressed state to the compressed state by an amount that ranges from about 0.003 inches to about 0.008 inches. Most preferably, the amount of compression of the thickness dimension T between uncompressed and compressed states is about 0.005 inches. This configuration provides a slight clearance between the flange wall128and valve support16. As a result, the illustrated flow control valve18can be precisely coaxially aligned with the valve support16, fitting14, and passageways48a,48b,48c, and the flange wall128can be compressed between the valve support16and fitting14while permitting the body118to flex normally to allow distal fluid flow.

Turning again toFIGS. 1-3, the valve18is preferably designed to prevent fluid flow in the proximal direction. More particularly, the valve18prevents proximal flow regardless of the back-pressure (i.e., the relative pressure differential experienced by the distal-facing surface120bof the wall120with respect to the pressure against the proximal-facing surface120aof the wall) across the valve18. In general, the back-pressure experienced by the valve18may correspond to a typical venous pressure of the patient. In certain circumstances (such as when drawing off fluids or when changing connectors or valve assembly components), the corresponding back-pressure may be higher than the typical venous pressure and could cause prior art valves to allow a proximal fluid flow. However, embodiments of the present invention prevent proximal fluid flow by utilizing the axially-extending boss62positioned proximally from the valve. As back-pressure increases, the pressure against the distal-facing surface120bof the wall120forces the wall in a proximal direction, thus compressing the valve18, or at least a portion of the valve18, against the boss62. Such a compression functions to compress the interior valve edges124together and against the boss62, thus sealing the valve18closed and preventing any fluid from traveling in the proximal direction.

In addition, in prior art valves, if the back-pressure exceeds a threshold amount, the pressure could cause the valve to mechanically invert, such that a distal end of the valve is forced proximally from its natural position. Such a mechanical inversion could cause the slit126of the valve18to remain open and permit unobstructed fluid flow in the proximal direction. Embodiments of the present invention prevent such mechanical inversion by use of the boss62acting as a back-stop for the valve18. For instance, with typical venous pressures (e.g., between about 0.3 psi to about 0.7 psi) being applied to the distal-facing surface120bof the wall120, the boss62prevents mechanical inversion, and the slit126of the valve18remains in a closed and sealed position. In addition, embodiments of the present invention may provide for the boss62to prevent a mechanical inversion of the valve18and a corresponding fluid flow in the proximal direction in response to extreme back-pressures, i.e., up to about 100 psi being applied to the distal-facing surface120b.

As best illustrated inFIG. 3, the valve18is also preferably designed to selectively prevent fluid flow in the distal direction when the valve is in the closed configuration. The valve18prevents distal fluid flow when a forward-pressure (i.e., the relative pressure differential experienced by the proximal-facing surface120aof the wall120with respect to the pressure against the distal-facing surface120bof the wall) across the valve18is below a predetermined cracking pressure. When a forward-pressure is applied to the proximal-facing side120aof the valve18(e.g., by injecting fluid or medication from a fluid supply) and such forward-pressure exceeds the cracking pressure, the valve18opens into an open configuration (where the interior valve edges124are shifted distally and away from each other) to allow fluid to flow distally through passageway48band into passageway48c. Embodiments of the present invention provide for the cracking pressure to be relatively low, thus corresponding to a low cracking pressure. In particular, the size, shape, and materials used in the manufacture of the flow control valve18naturally facilitate a low cracking pressure. In addition, the fluidic chamber134provides a natural cavity for the fluid to collect, wherefrom the fluid acts against the proximal-facing surface120aof the valve18. The fluid pressure on the proximal-facing surface120aworks to assist in opening the valve, thus enhancing the low cracking pressure of the valve.

In operation, the valve assembly12permits distal fluid flow from the fluid source (not shown) to the peripheral catheter20when the front-pressure exceeds the cracking pressure. Thus, the fluid from the injection source travels through the passageway48bof the valve support16and through the one or more channels88in the boss62and collects in the fluidic chamber134. The fluid begins to build up pressure against the proximal-facing surface120aof the valve18as it collects in the fluidic chamber. Once the pressure in the fluidic chamber exceeds the cracking pressure, the interior valve edges124are shifted in the distal direction and at least partly away from each other to open the slit126and allow fluid to pass from the passageway48bto the distal passageway48c. As discussed above, embodiments of the present invention provide for the slit126to vary in length to affect the cracking pressure necessary to open the valve and to allow fluid to flow in the distal direction. Thus, slit126with a relatively longer length will have a lower cracking pressure, such that the pressure necessary to open the valve18to allow a distal fluid flow will be less. Conversely, slit126with a relatively shorter length will have a higher cracking pressure, such that the pressure necessary to open the valve18will be greater.

As previously discussed, the valve assembly12can be used in other applications or with other types of connection components, tubing, etc. For instance, as illustrated inFIGS. 9-13, a variant of the valve assembly12may be used as part of an inline check-valve system138. In inline system138, inline valve assembly140is positioned inline between distal and proximal tubular members142,144. The inline valve assembly140is structurally similar in all respects to the valve assembly12, except that valve assembly140includes luer slip locks as opposed to luer locks on its distal and proximal ends. Specifically, instead of using the luer lock fitting14, the valve assembly140includes a slip luer fitting146on its distal end. The slip luer fitting146is structurally similar in all respects to the luer lock fitting14, except that the luer lock mating parts of fitting14are replaced with a distal annular inner barrel150and a distal annular outer connection wall152. Similarly, instead of using the valve support16, the valve assembly140includes a luer slip valve support148on its proximal end. The slip luer valve support148is structurally similar in all respects to the valve support16, except that the luer lock mating parts of valve support16are replaced with proximal annular inner barrels154and proximal outer connection walls156. The barrels150,154and walls152,156of the slip luer lock fitting146and the slip luer valve support148are sized such that the tubular members142,144may be attached to the fittings and valve support by inserting the tubular members between the barrels and the outer walls. The outer walls152,156may be positioned at such a distance from the barrels150,154that the tubular members142,144are securely held in place by the compression of the outer walls and the barrels. In such an embodiment, fluid may be delivered from the tubing that connects the inline support assembly and will flow through the valve assembly140as was described in previous embodiments for valve assembly12. After the fluid has passed through the valve assembly140, it continues on through the tubing that connects to the distal end of the valve assembly. As can be appreciated, the inline check-valve system138only allows fluid to flow in the direction permitted by the flow control valve, i.e. from proximal end to distal end. Such restriction is caused by the boss62functioning to prevent the backflow of fluids in a proximal direction into the fluid source or otherwise upstream when infusing fluids or medication downstream.

As illustrated inFIGS. 14-16, embodiments of the present invention additionally provide for a variant of the valve assembly12to be used in a Y-site check valve system160. In such an embodiment Y-site check valve assembly162is positioned at the proximal end of a first leg164of the Y-site system160. The Y-site system160includes a second leg166that joins the first leg164at a joint168that is some distal distance from the valve assembly162. The Y-site system160further includes a single base leg170that is attached distally to the joint168. The Y-site valve assembly162is structurally similar in all respects to valve assembly12except that the luer lock fitting16is replaced with a slip luer fitting172. In addition, the slip luer fitting172is structurally similar in all respects to the luer lock fitting14with the exception that the luer lock mating parts of fitting14are replaced with a distal annular inner barrel174and a distal outer connection wall176. In certain embodiments, the slip luer fitting172may be identical to slip luer fitting146from the inline check valve system138. In additional embodiments, the wall176of slip luer fitting172may be substantially shorter than the wall152from the slip luer fitting146. However, either embodiment provides for a proximal end of the first leg164to fit onto the slip luer fitting172by being positioned over the fitting's inner barrel174. A solvent may be applied to the proximal end of the first leg164and the inner barrel174to secure the first leg and the inner barrel together. In certain embodiments, the Y-site check valve system160includes a valve support178with a luer lock connection180, with the valve support178similar in all respects to the valve support16described above. Once each of the above-described components are connected, the Y-site system160facilitates further attachments and connections to be attached to the luer lock connection180of the valve support178. In addition, a free end of the second leg166and a free end of the single base leg may include slip luer fittings, such that tubular members182may be inserted onto each of the free ends. The Y-site valve assembly162permits fluids and medication to pass through the first leg164of the valve system160and to mix and combine with the fluids and/or medication flowing through the second leg166at the joint168of the valve system. In addition, the Y-site valve assembly162prevents for reflux of the fluid, such that incompatible fluids will not be intermixed beyond any proximal distance from the valve of the valve assembly.

As illustrated inFIGS. 17-19, embodiments of the present invention additionally provide for a variant of the valve assembly12to be used in a manifold check valve system184. The manifold check valve system184is comprised of a base module186, two or more manifold check valve assemblies188secured to the base, and a barrel-shaped interconnect190that fluidly connects the valve assemblies188. The base186may be constructed of any suitable medical grade material, such as, for example, polyethylene, polyvinyl chloride, Teflon, or mixtures thereof. The base provides a secure support for the valve assemblies188and interconnect190. The interconnect190may similarly be made of polyethylene, polyvinyl chloride, Teflon, or mixtures thereof; however, in certain embodiments, the interconnect may simply be a section of silicone elastomer or polyurethane tubing. The valve assemblies188are structurally similar in all respects to the valve assembly12except that in place of luer lock fitting14, the valve assemblies188include a manifold fitting192on distal ends of the valve assemblies188. The manifold fitting192functions similar to the luer lock fitting14and slip luer fittings146,172, in that it receives the flow control valve18and secures the valve in place against the valve support194. However, the manifold fitting does not include a connector on its distal end. Instead, the manifold fitting192includes a tubular passageway196positioned perpendicularly to the direction of fluid flow through the valve assemblies188. The manifold assemblies188include openings198that fluidly connect the flow control valve18to the tubular passageway196. Thus, as fluid or medication flow distally through the manifold valve assemblies188, they pass through the flow control valve18and on into the tubular passageway196. Such an embodiment provides for a plurality of fluids and medications to be introduced from each of the valve assemblies188and to be intermixed within the tubular passageway196. As with all embodiments of the present invention, the valve18and the boss62of the valve assemblies188prevent fluid from backflowing from the tubular passageway196back through the valve assemblies188in a proximal direction past the flow control valve18. In additional embodiments, the manifold check valve system184may include a plurality of valve assemblies188connected in series, such that multiple sources of fluid or medications can be introduced and mixed without concern for intermixing of the fluids or medications in a proximal direction past the manifold valve assemblies188.

In certain embodiments, the components of the manifold check valve system184may fit together in a modular design. Such a modular design facilitates a functional fit of the components, while permitting exterior portions of the components to form continuous connections. For instance, as illustrated inFIG. 17, exterior portions of the manifold fittings192connect in a continuous manner with exterior portions of the interconnect190, such that although the fittings and manifold are separate components, they fit together to give an appearance of a single continuous component. Embodiments of the present invention provide for various check valve components to fit together in such modular design.

As can be appreciated, embodiments of the present invention contemplate the use of various mixing and matching of embodiments of the present invention as may be required. As a non-limiting example, an inline check valve assembly140may be attached to an end of the manifold system184inline with the tubular passageway196. Such an embodiment would function similar to the manifold application described above; however, the inline check valve140would only facilitate the flow of fluid in a single direction through the manifold, thereby restricting reflux past the flow control valve and into the manifold. Such an embodiment would further reduce the concern for the unwanted reflux and intermixing of fluids or medications within the manifold.