Needleless access connector and method of use

Abstract

A positive-displacement needleless access connector is disclosed that has a housing with a first luer fitting at a proximal end thereof, a base with a second luer fitting at a distal end thereof, and a valve element with a proximal end that creates a seal at the first luer fitting and fastens to the base so that a surface of the valve element is substantially flush with a surface of the base.

Claims

1. A positive-displacement needleless access connector comprising: a housing that has a first luer fitting at a proximal end thereof; a base that has a vent and a second luer fitting at a distal end thereof; and a valve element with a septum and a proximal end that creates a seal at the first luer fitting and fastens to the base; wherein the base and the housing have corresponding v-shaped mating surfaces such that when the base is fastened with the valve element and the housing, an air passageway is defined between the septum, the vent, and the atmosphere.

2. The positive-displacement needleless access connector of claim 1 in which a distal end of the valve element fastens to the base using a snapping mechanism.

3. The positive-displacement needleless access connector of claim 1 in which the housing is coupled to the base using a key and slot fitting.

4. The positive-displacement needleless access connector of claim 1, wherein the base and the valve element couple to each other to create an assembly that has a greatest outer diameter that is smaller than an inner diameter of the housing.

5. The positive-displacement needleless access connector of claim 1 in which an outer surface of the valve element is substantially flush with an outer surface of the base.

6. The positive-displacement needleless access connector of claim 1 in which the vent comprises a Y-shaped air passageway from the septum to a distal end of the base.

7. The positive-displacement needleless access connector of claim 6 in which the Y-shaped air passageway comprises triangularly shaped branches.

8. The positive-displacement needleless access connector of claim 1 in which the housing and the base have corresponding, mating surfaces.

9. The positive-displacement needleless access connector of claim 8 in which the corresponding, mating surfaces comprise a slot and key fitting.

10. The positive-displacement needleless access connector of claim 1 in which the vent comprises at least one branch that broadens along the air passageway.

11. The positive-displacement needleless access connector of claim 10 in which the air passageway comprises triangular broadening.

12. The positive-displacement needleless access connector of claim 11 in which the triangular broadening broadens from a center axis of the base to an outer surface of the base.

13. The positive-displacement needleless access connector of claim 1 in which the base comprises a flow channel, and the housing, valve element, and base define a fluid flow path between the first luer fitting, the flow channel, and the second luer fitting.

14. The positive-displacement needleless access connector of claim 13 in which the air passageway is sealed from the fluid flow path.

15. The positive-displacement needleless access connector of claim 13 in which the v-shaped mating surfaces direct the flow path from the first luer fitting into the flow channel.

16. The positive-displacement needleless access connector of claim 13 in which the vent is fluidly isolated from the flow channel by the v-shaped mating surfaces.

17. The positive-displacement needleless access connector of claim 1, wherein the valve element fastens to a proximal end of the base using an interlocking snap fitting.

18. The positive-displacement needleless access connector of claim 17 in which the air passageway from a septum of the valve element comprises a single path axially disposed within a portion of the base that forms part of the snap fitting.

19. The positive-displacement needleless access connector of claim 18 in which the air passageway further comprises branches from the single path to the atmosphere.

20. The positive-displacement needleless access connector of claim 19 in which the branches are triangularly shaped.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) For a more complete understanding of the present invention, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:

(2) FIG. 1A is a cut-away view of a current needleless access connector. FIG. 1B shows a collapsible valve element in the collapsed position after insertion of a male luer into a female luer.

(3) FIGS. 2A and 2B provide an exploded illustration of an exemplary positive displacement needleless access connector, adapted according to one embodiment of the invention.

(4) FIGS. 3A and 3B provide an exploded illustration of the exemplary positive displacement needleless access connector, adapted according to one embodiment of the invention.

(5) FIG. 4 is a see-through illustration of the exemplary connector in use, according to one embodiment.

(6) FIG. 5 is a cross-section illustration of the exemplary connector, adapted according to one embodiment, which is ninety degrees rotated from the cross-sections of FIGS. 2A, B and 3A, B.

(7) FIG. 6 is an illustration of the exemplary connector assembled and ready for use, according to one embodiment.

(8) FIG. 7 is an illustration of an exemplary connector, adapted according to one embodiment.

(9) FIG. 8 is an illustration of an exemplary method for manufacturing a positive displacement needleless connector according to one embodiment.

DETAILED DESCRIPTION

(10) FIGS. 2A and 2B provide an exploded illustration of exemplary positive displacement needleless access connector 200, adapted according to one embodiment of the invention. FIG. 2A is a cut-away view, whereas FIG. 2B shows the exterior of connector 200.

(11) Connector 200 has three basic partsbase 210, valve element 220, and housing 230. Housing 230 has female luer fitting 231 at the proximal end, which connects, for example, to a fluid reservoir, such as an IV bag. Base 210 and threads 232 form a male luer fitting at the distal end of connector 200, the male luer fitting connecting to, for example, a catheter that is in communication with a patient. Valve element 220 includes septum 221, which is filled with air and vents to the atmosphere as it is compressed and uncompressed, as explained in more detail below.

(12) FIGS. 3A and 3B provide an exploded illustration of exemplary positive displacement needleless access connector 200, adapted according to one embodiment of the invention. FIG. 3A is a cut-away view, whereas FIG. 3B shows the exterior of connector 200, and both FIGS. 3A and 3B show base 210 fastened to valve element 220.

(13) Base 210 and valve element 220 are coupled together using, in this embodiment, an interlocking male/female fitting 250, referred to herein for convenience as a snap fitting. The top of valve element 220 that is the female part of the snap fitting 250 is made small enough so that is has a tight, sealing squeeze at the corresponding portion of base 210 that forms the male portion of snap fitting 250. In many embodiments, the seal at the snap fitting 250 is airtight, at least at normal operating temperatures and pressures, in order to keep the air separate from the fluid in connector 200. During manufacturing, base 210 and valve element 220 can be fastened together by forcing them together, either by hand or by machine. In some embodiments, about a pound of force is sufficient to make the connection, and about two pounds is sufficient to break the connection, though various embodiments may differ.

(14) While FIGS. 3A and B show a snap fitting 250, the scope of embodiments is not so limited. For instance, other embodiments may employ different types of fastening fittings, such as threaded assemblies or other fittings.

(15) In the exemplary embodiment of FIGS. 3A and 3B, the outside surfaces of base 210 and valve element 220 are flush at snap fitting 250. For real-world devices it is understood that the outside surfaces of valve element 220 and base 210 will rarely be exactly flush, but some amount of tolerance (e.g., about 2%) is acceptable in some embodiments. Thus, connector 200 replaces the flange of conventional positive displacement devices (e.g., flange 105 of FIG. 1A) with the snap fitting 250 and flush outer surface shown in FIGS. 3A and 3B. The shape of valve element 220, therefore, has a narrower profile, and can be used in narrower-profile connectors.

(16) Base 210 and valve element 220 fasten together to form an assembly that is placed into housing 230. Connector 200 uses a somewhat v-shaped fitting to mate base 210 to housing 230. Complementary surfaces 211 and 233 are basically v-shaped but have slight curvature and fit together to hold base 210 in place when base 210 is inserted into housing 230. As base 210 is inserted, the complementary surfaces 211, 233 self-correct the alignment of base 210 with respect to housing 230, acting like a cam. Thus, if base 210 is inserted some arbitrary number of degrees out of alignment, complementary surfaces 211, 233 (once contacted) rotate base 210 into place. As a result, base 210 sits precisely, and after the weld is made, air vents 212 will be able to vent to the atmosphere while distal flow channels 213 are connected to the male luer outlet of base 210.

(17) Distal flow channels 213 and air vents 212 are perpendicular to each other in this embodiment. Thus, one of two air vents 212 is shown in FIG. 3B, whereas distal flow channels 213 are shown in cross-section in FIG. 3A. Flow and venting are shown in more detail in FIG. 4.

(18) FIG. 4 is a see-through illustration of exemplary connector 200 in use, according to one embodiment. In FIG. 4, fluid is being transferred from male luer connector 410, which is engaged with female luer fitting 231, through housing 230, through the male luer outlet of base 210 and into female luer fitting 402. Such an example may include transferring fluid from an IV bag {not shown) into a patient's bloodstream. While FIG. 4 shows flow into a patient, it is understood that various embodiments of the invention also facilitate flow of fluids from a patient.

(19) When there is no connection at the female luer fitting 231, valve element 230 creates a seal at the proximal end of female luer fitting 231 as well as at shoulder 234. Such seal prevents the flow of fluids through connector 200 when not in use. Also, the seal at the proximal end of fitting 231 creates a flush surface that is swabbable. The seals at the proximal end of female luer fitting 231 and at shoulder 234 are shown in FIG. 5.

(20) During use, male luer fitting 401 collapses valve element 220 and breaks the seals at shoulder 234 and at the proximal end of fitting 231. Fluid is then free to flow around valve element 230 and through housing 230 via proximal flow channels 403, which are formed into the inner surface of housing 230. The weld at surfaces 211, 233 stops the fluid so that the fluid flows around the v-shape and into the distal flow channels 213, where the fluid is directed out through the male luer outlet of base 210. Air from septum 221 is vented to the atmosphere through air vents 212 and into threaded chamber 404, which is part of the male luer fitting formed by base 210 and housing 230. The air passageway is defined by vent 212 and the inner surface of housing 230, and the weld at surfaces 211, 233 creates a seal that keeps the air flow separate from the fluid flow. The threaded chamber 404 is not airtight, even when engaged with female fitting 402, thereby allowing septum 221 to communicate with the ambient atmosphere as valve element 220 is compressed, as in FIG. 4, or uncompressed.

(21) FIG. 5 is a cross-section illustration of exemplary connector 200, adapted according to one embodiment, which is ninety degrees rotated from the cross-sections of FIGS. 2A, B and 3A, B. Of note in FIG. 5 is the air passageway from septum 221 to the atmosphere. The air passageway includes single vent 501, formed in base 210, and vents 212. The single vent 501 and the vents 212 form a substantially Y-shaped air passageway. This is in contrast to prior designs (not shown) that include two or more separate vents, formed in the y-axis direction (axially), directly connecting the atmosphere to the septum.

(22) During conventional manufacturing techniques, an injection molding technique is used, and the two or more separate vents are created using long, thin pins inserted into the mold cavity when the material is hot. When the mold is opened, the long, thin pins are removed to form the two or more separate vents. However, long, thin pins have a tendency to break during use. The general rule is that shorter and thicker pins last longer.

(23) By contrast, base 210 has relatively wide and short vents 212 that can be formed by correspondingly-shaped metal pieces in the mold. The air passageway has a triangular broadening in each vent 212 from the center axis to the outer surface of base 210. The correspondingly-shaped metal pieces (not shown) are thicker and shorter than the long, thin pins of conventional techniques and are, therefore, less subject to breaking. Single channel 501 is made relatively wide, and it is placed in the portion of base 210 that corresponds to the male portion of snap fitting 250. Furthermore, since single channel 501 does not have to traverse the full length from septum 221 to threaded chamber 404, it avoids cramping the fluid flow path. Accordingly, single channel 501 is not made with a long, thin pin either.

(24) FIG. 6 is an illustration of exemplary connector 200 assembled and ready for use, according to one embodiment. Housing 230 may be made of material including polycarbonate, polystyrene and acrylonitrile butadiene styrene. Housing 230 includes female luer fitting 231, which, in some embodiments, meets ISO standard 594. Similarly, the configurations of the male luer at the distal end of housing 230 and formed with base 210, in some embodiments, meets ISO standard 594. Valve element 220 is disposed within housing 230 and may be made of elastic material such as silicone rubber, which is deformable and biocompatible.

(25) FIG. 7 is an illustration of exemplary connector 700, adapted according to one embodiment. Connector 700 is similar to connector 200 (e.g., FIGS. 2-6) but uses a slot and key fitting to mate housing 730 to base 710, instead of the v-shaped fitting featured in connector 200. In a slot and key configuration, base 710 has a protrusion (key) that is sized to fit into a slot in the inner surface of housing 730 (or vise versa). During manufacture, base 710 and valve element 220 are inserted into housing 730 and turned it until the slot mates with the key. Base 710 and housing 730 are then welded. The scope of embodiments is not limited to a slot and key fitting or a v-shaped fitting, as any of a variety of techniques for mating a base and a housing can be used in a variety of embodiments.

(26) FIG. 8 is an illustration of exemplary method 800 for manufacturing a positive displacement needleless connector according to one embodiment. Method 800 may be performed, for example, by a human and/or one or more machines.

(27) In block 801, a distal end of the valve element is fastened to a proximal end of the base. The fastening creates a seal between the valve element and the base separating the septum from a fluid flow path between the first and second luer fittings. Block 801 creates an assembly, such as that shown in FIG. 3A, which includes a valve element and a base mated together. In one example, the valve element and base are mated using a snap fitting, though other fastening techniques can be used in other embodiments.

(28) In block 802, the valve element and the base are disposed within the housing. For instance, a v-shaped fitting can be used, such as that shown in FIGS. 3A and 3B, that self-aligns the base and housing, though other fittings, such as a key and slot and can be used. When the valve and base are disposed within the housing, the proximal end of the valve element creates one or more seals at the proximal end of the housing.

(29) In block 803, the base and housing are permanently affixed. Various techniques can be used in block 803, such as ultrasonic welding, applying adhesives, and the like. In this example, the base and housing fit together tightly so that a seal is created that separates air venting paths from fluid flow paths after the base and housing are permanently affixed. Various embodiments are not limited to the process shown in FIG. 8, as various actions may be added, omitted, rearranged, or modified.

(30) Some embodiments may enjoy one or more advantages over prior solutions. In one aspect, elimination of the flange of FIGS. 1A and 1B decreases the size of the valve element and, in turn, the connector as a whole. A connector with a smaller volume is generally expected to have a smaller priming volume, as well, which may reduce fluid and waste and may be more visually appealing to health care professionals. Additionally, some embodiments have a reduced overall width, which is generally more comfortable to a patient when catheter is taped to the skin close to the connector.

(31) Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.