WO2001034059A1

WO2001034059A1 - Teat infusion syringe and related components

Info

Publication number: WO2001034059A1
Application number: PCT/US2000/026273
Authority: WO
Inventors: Paul Reuben Klink; John Charles Kube; Scott Edward Roland; John Inglis Douglas Wilkinson
Original assignee: Eli Lilly And Company
Priority date: 1999-11-05
Filing date: 2000-10-24
Publication date: 2001-05-17
Also published as: AU1569301A

Abstract

A teat infusion syringe (10) includes a syringe body (11) and associated first cannula (12), a cannula cover (13) mounted to the syringe body (11) and including a second cannula (14) extending distally therefrom, and an end cap (15) mounted to the cannula cover (13). The cannula cover (13) includes means for sealing with the end of the first cannula (12), and the end cap (15) includes means for sealing the end of the second cannula (14) when in place on the cannula cover (13). In one embodiment, there is provided an annular sealing ridge (21a) surrounding the first cannula (14a) for sealing with the teat when the first (14a) cannula is used to infuse material into the teat canal. In another embodiment, the cover (13) includes an annular sealing ridge (21) surrounding the second cannula (14) for sealing with the teat when the second cannula (14) is used.

Description

TEAT INFUSION SYRINGE AND RELATED COMPONENTS

BACKGROUND OF THE INVENTION The present invention relates to the field of syringes for infusion of materials into the teat canal, and more particularly to a syringe design which provides a seal between the teat and the cannula to minimize leakage during infusion of material into the teat.

Bovine mastitis is a serious problem which afflicts a large number of dairy cows. This mastitis, or inflammation of the cow's mammary gland, strikes substantial percentages of cows in dairy herds and has a detrimental effect on milk production and herd profitability. The generally followed method of treatment for bovine mastitis has been the administration of various antibiotic preparations into the cow's udder through the teat canal. A mastitis infusion syringe, which carries the antibiotic preparation, typically is equipped with an insertion cannula having a length of 15 to 25 mm. This cannula and syringe assembly is provided from the antibiotic supplier as a molded plastic, disposable unit which is prefilled with the treatment antibiotic. A single piece protective cap, which typically snaps onto the hub of the syringe at the base of the cannula, is used to cover the cannula prior to use. At the time of treatment, the protective cap is removed and the cannula end is inserted into the cow's teat end. In one method of treatment, the cannula end is passed through the teat canal and positioned within the teat cistern. Once the cannula has been so positioned, the syringe is utilized to deposit the treatment antibiotic directly into the cow's teat cistern.

In an alternate treatment method, the antibiotic is released within the teat canal. It has been indicated that in some instances infection in the teat canal may be carried into the teat cistern by the cannula during full cannula insertion. The cow's teat canal is approximately 1 cm in length and has a very narrow lumen. This canal helps to prevent bacteria from entering the cow's udder. For these and other reasons, an alternate technique involves the partial insertion of the cannula into the teat canal, for example to a distance of about 3 mm.

A need has therefore been identified for a dual purpose syringe which facilitates the use of the syringe for insertion alternately to either the full or the partial positions for administering an antibiotic. Several such syringes have been proposed in the prior art.

One version of a dual purpose mastitis syringe is described in United States Patent No. 4,981,472, issued to Enis on January 1, 1991. This patent shows a syringe which includes a first cannula attached to the syringe body, and a second cannula received over and attached to the first cannula. Either one of the cannulae is sized to partial insertion into the teat canal and the other cannula is sized for full insertion through the teat canal. The two cannulae are snap fit together, enabling the user to employ either the outer cannula for its designed length of insertion, or to remove the outer cannula and use the differently sized inner cannula for the alternate distance of insertion.

In United States Patent No. 4,850,970, issued to Sutherland on July 25, 1989, there is described a Two Part Mastitis Cannula Cap used with a mastitis syringe. The syringe includes an insertion cannula of sufficient length to be used for full insertion through the teat canal. The cap includes a first member which is attached to the syringe and surrounds a portion of the cannula. However, this first member is sized such that the cannula extends a short distance beyond the open end of the member. In this manner, with the first cap member removed, the full length of the cannula is exposed, and the cannula may be fully inserted through the teat canal. However, with the first cap member in place, only a short portion of the cannula is exposed beyond the cap member, thereby limiting the extent to which the cannula can be inserted into the teat canal, corresponding to the desired partial insertion. The second cap member covers the exposed end of the cannula prior to use.

A similar device is disclosed in United States Patent No. 5,059,172, issued to Sutherland on October 22, 1991, in which the cap includes an end portion which is removable to expose a limited length of the underlying cannula. A special form of a cap for a similar syringe having an inner cap member which partially covers the cannula is discussed in United States Patent No. 5,009,640, issued to Pyret on April 23, 1991.

A related syringe design is shown in European Patent Application, Publication No. EP 0 540 493 Bl, published on March 20, 1996. This application shows a mastitis syringe of the same general type as the Sutherland design in which a single cannula is covered by a cap system that can permit full or partial covering of the cannula tip. The cap in this EP application is initially a one-piece member that includes a weakened portion that permits the end of the cap to be separated from the remainder of the cap, such as by twisting it off. Once this distal portion is removed, the tip of the underlying cannula and a short length of the cannula is exposed for use in partial insertion into the teat canal. In addition, the portion of the cap which remains when the distal end is removed includes a portion which is spaced from the cannula, thereby providing a cavity surrounding the cannula. The EP application describes that this annular cavity is provided for the purpose of trapping microbial debris and other contaminants which may have accumulated around the opening of the teat channel. These and other mastitis syringe designs have been proposed in the art, but there has remained a need for improvements in mastitis syringes that facilitate the use of such syringes for either full or partial insertion into the teat canal. The present invention provides a novel syringe design which provides superior sealing between the cannula and the teat canal, and which provides other advantageous features for a single or dual purpose syringe for use in administering medications and other materials to the teat canal. It is an object of the present invention to provide a teat infusion syringe which provides a fluid tight seal with the teat when material is being infused into the teat canal, particularly when infusion is only part way into the canal.

A further object of the present invention is to provide a teat infusion syringe which provides fluid tight sealing between a first cannula and a cannula cover, and between a second cannula and an end cap.

It is another object of the present invention to provide a cannula cover which is useful with a teat infusion syringe, and which provides a fluid tight seal with a first underlying cannula, and which includes means for sealing with the teat when material is being infused into the teat canal.

Further objects and advantages of the present invention will be apparent from the descriptions and accompanying drawings which follow.

In one aspect of the invention there is provided a teat infusion cannula cover assembly for reception over a syringe body and associated first canula, the cover assembly including a cover having a central lumen and an open proximal end for reception therein of the first cannula, the proximal end of said cover further defining attachment means for attachment to at least one of the syringe body and the first cannula, the central lumen defining an end shoulder for sealing engagement of the tip of the first cannula; and a second cannula attached to the cover and extending distally therefrom, the second cannula having a lumen communicating with the central lumen of said cover; said cover defining an annular sealing ridge surrounding said second cannula for sealing with a teat when said second cannula is inserted into a teat canal. In another aspect of the present invention, there is provided a teat infusion syringe which includes a syringe body and an associated first cannula secured to the syringe body, and a cannula cover secured to at least one of the syringe body and the first cannula and including a central lumen and an open proximal end for reception therein of said first cannula, the cannula cover further including a second cannula extending distally therefrom and an annular sealing ridge surrounding the second cannula, the second cannula having a lumen communicating with the central lumen of the cannula cover. The sealing ridge forms a fluid tight seal with a teat when the second cannula is used to infuse material into a teat canal. In a third aspect of the invention, there is provided a teat infusion syringe which comprises a syringe body; a first cannula secured to said syringe body; and a cannula cover secured to at least one of said syringe body and said first cannula, said cannula cover including a central lumen and an open proximal end for reception therein of said first cannula, said cannula cover further including a second cannula extending distally therefrom, the second cannula having a lumen communicating with the central lumen of said cannula cover, at least one of said syringe body and said first cannula defining an annular sealing ridge surrounding said first cannula for sealing with a teat when said first cannula is inserted into a teat canal.

FIG. 1 is a perspective view of an assembled syringe constructed in accordance with a preferred embodiment of the present invention.

FIG. 2 is an exploded, perspective view of a cannula, cover and end cap according to the embodiment of FIG. 1.

FIG. 3 is a side, elevational view of a portion of the cannula and a portion of the syringe body, in accordance with the embodiment of FIG. 1. FIG. 4 is a side, cross-sectional view of the cannula and body portion of FIG. 3.

FIG. 5 is a side, elevational view of the cannula cover in accordance with the embodiment of FIG. 1.

FIG. 6 is a side, cross-sectional view of the cover of FIG. 5.

FIG. 7 is a side, elevational view of the end cap in accordance with the embodiment of FIG. 1.

FIG. 8 is a side, cross-sectional view of the end cap of FIG. 7. FIG. 9 is a side, elevational view showing the cannula cover attached to the base of the cannula, in accordance with the embodiment of FIG. 1.

FIG. 10 is a side, elevational view showing the end cap, cannula cover, and cannula as assembled. FIG. 11 is a side, cross- sectional view of the assembly of FIG. 10.

FIG. 12 is a side, cross- sectional view of a first alternate embodiment of a syringe having a short cannula and associated sealing ridge attached directly to the syringe body.

FIG. 13 is a side, elevational view of the embodiment of FIG. 12 showing the end cap received upon the cannula cover. FIG. 14 is a side, cross-sectional view showing a second alternate embodiment of the end cap and cannula cover, assembled onto a first cannula and syringe body.

FIG. 15 is a side, cross-sectional view of a third alternate embodiment of the syringe.

For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.

The teat infusion syringe of the present invention provides a simple and reliable device which is readily fabricated and used. The syringe includes a novel design for a cannula which includes an annular seal between the cannula and the teat canal. While shown in the form of a dual cannula syringe, it will be appreciated that this superior sealing structure is equally useful for a single cannula syringe employing this configuration.

Referring in particular to the drawings, there is shown a syringe 10 constructed in accordance with the present invention. The syringe 10 includes a body 11 including a first cannula 12 (FIG. 2) secured thereto. A cannula cover 13 is removably attached to the body or first cannula, and includes a second cannula 14 (FIG. 2). An end cap 15 is mounted over the cannula cover 13 to protect the second cannula 14. As shown, the device is readily assembled to form the syringe unit shown in perspective in FIG. 1. The end cap 15 can be removed to expose the underlying cannula 14 for its use. Alternatively, the cannula cover 13 may also be removed, either separately from or in unison with the end cap 15, to expose the first cannula 12 for use.

The syringe body 11 and first cannula 12 are shown in greater detail in FIGS. 3 and 4. The body and other portions of the syringe, for example the plunger, may be of any of a variety of designs. Suitable components of this type are well known to those skilled in the art, and therefore are not further described herein. The cannula 12 is sized and shaped for ready reception into the teat canal, and is preferably provided with a length suitable for full insertion through the teat canal. It will be appreciated, however, that this cannula may have other lengths, particularly if the second cannula 14 is sized for full insertion, in which case the first cannula will preferably have a different length, e.g., one adapted for only partial insertion into the teat canal.

The cannula 12 is preferably formed integral with the body 11 , or is securely affixed thereto. In addition, there are provided certain features which are suited for cooperation with corresponding portions of the cannula cover. In particular, the base 16 connecting the cannula with the body is preferably provided with a groove 17 which cooperates with a bead on the interior of the cannula cover to provide a snap fit of the cover to the body.

The cannula cover 13 and associated second cannula are shown in detail in FIGS. 5 and 6. The cover includes a main body portion 18 which includes a base 19 for securement of the cover to the underlying cannula base 16. For example, the cover is provided with an internal ridge or bead 20 which is sized and positioned to be received as a snap fit within the groove 17 of the cannula base 16. The interior of the base portion 19 is preferably shaped complementary with the exterior of the first cannula base 16 to provide a secure and solid receipt of the cover. It will be appreciated, however, that alternate forms of attachment may also be used, including attachment of the cover directly to the syringe body 11 or the first cannula 12. The cover is removably attached to the syringe unit in a fashion which provides sufficient securement of the cover when it is desired to be maintained in place, but which also permits ready removal of the cover by the user when appropriate.

The cover also includes the second cannula 14 which is provided with the desired shape and length for desired reception within the teat canal. As previously indicated, the preferred embodiment shown in FIG. 2 includes an outer cannula which is sized for partial insertion into the teat canal, with the inner cannula 12 being sized for full insertion. Various other sizes for each of these cannulae may be used, depending on the ultimate use of the syringe. Surrounding the cannula 14 and formed by the cover 13 is a sealing ridge 21 which forms with the cannula 14 an annular recess 22 for reception of the teat therein. The ridge is sized to fit the end of the teat, and the cannula 14 extends beyond the ridge the desired distance for insertion into the teat canal. The ridge 21 is shown to have an interior taper. However, the ridge may alternately be formed flat or be provided with varying shapes and angles to maximize the sealing with the teat.

The cover 13 further includes a complementary shape for reception of and securement with the end cap 15. For example, the cover is shown having an external ridge 23 that cooperates with the end cap for a snap fit engagement therewith. The cover also may include surface treatment or features to facilitate handling by the user of the syringe. For example, the cover 13 is shown with several radially-extending flanges 24 that make it easier for the user to grasp the cover for removal.

The end cap 15 is shown in greater detail in FIGS. 7 and 8. The end cap includes a first portion 25 that is configured to be received over and attached to the underlying cover 13. For example, portion 25 defines an internal ridge or bead 26 that is received over the ridge 23 of the cover as the cap is installed onto the end of the cover, thereby providing a snap fit between the two components. The end cap further includes a central portion that includes a central projection 27 for sealing with the second cannula 14. Finally, the tip 28 of the end cap 15 extends distally of the central portion. The first portion 25 and/or the tip 28 are provided with flanges 29 and 30, respectively, to facilitate handling of the end cap by the user.

The assembly of the cover 13 to the syringe body 11 and first cannula 12 is more fully depicted in FIGS. 9 and 10. As previously described, the cover 13 is securely attached to the underlying body 11 and cannula 12, preferably by a snap fit between the components. Referring in particular to FIG. 11 , it is shown that the snap fit is facilitated by the provision of a taper 31 on the outside surface of the base 16. The bead 20 is sized to ride over the tapered surface 31 and thereby be flexed outwardly as the cover is moved down onto the syringe body. The bead will therefore snap into position once it passes the end of the taper and will be securely received within the groove 17. Similarly, the cover is provided with a tapered outer surface 32, and in the same fashion the bead 26 rides outwardly along the taper and snaps into position below the ridge 23 to provide a secure, snap fit of the end cap onto the cover. The sealing of the cannulae is also more fully depicted in FIG. 11. The cover 13 includes a narrowed internal lumen 44 for reception of the distal end 33 of the first cannula 12. Also, the cover includes a shoulder 34 positioned to bear against the tip of the cannula 12 when the cover is in position. It will further be noted that the groove 17 is provided with a tapered shoulder 35 that mates with a complementary tapered shoulder 36 to provide the attachment of the bead 20 within the recess 17. By having these two tapered surfaces, the cover is urged in the direction to the left in the drawings, thereby pulling the shoulder 34 against the end of the cannula 12 to enhance the seal between the two members. The provision of a fluid tight seal between the cannula 12 and the cover 13 ensures against leakage from the cannula into the annular area 37 between the two components.

A similar sealing engagement is provided between the end cap 15 and the second cannula 14. First, the projection 27 is positioned and sized to be received within the lumen 38 of the cannula 14. The annular tip of the cannula is thereby received within the inwardly-tapered, annular recess 39 of the end cap. The bead 26 of the end cap and the ridge 23 of the cover include mutually- facing tapered surfaces 40 and 41 , respectively, to urge the end cap in the direction to the left in the drawings, and to thereby seal the tip of the cannula 14 within the annular recess 39.

In an alternate embodiment, the same connectivity is provided, but using a longer end cap. Therefore, as shown in FIGS. 12 and 13, the cover 13a includes a tapered surface 41a that is located farther from the distal tip than ridge 23 of the previous embodiment. The end cap 15a is similarly modified to move the location of the corresponding engagement surface such that it is positioned to be received against the surface 41a when the cap is received upon the cover 13a. In this manner, a longer outer end cap 15a is provided which has an increased outer surface for gripping, thereby minimizing the possibility of contamination of the underlying cover by the user when the end cap is removed. In FIG. 14 there is shown an alternate embodiment of the syringe of the present invention. This embodiment is substantially the same as for the prior embodiment. Identical parts are therefore shown with the same numbers, and similar parts are identified with the corresponding number followed with the "prime" designation, e.g., 13'. In particular, the embodiment of FIG. 14 includes a modified sealing ridge 21' which is narrower than for the prior embodiment. The corresponding portion 42 of the cover 13' is therefore narrowed, resulting in a shoulder 43. However, aside from these general differences, the functional design of the components, and their interrelationships, remain the same. In another embodiment, it will be appreciated that the shorter cannula 14 and surrounding sealing ridge 21 could be provided as the interior cannula attached directly to the body 11. The cover 13 then includes the relatively longer cannula, and an elongated end cap 15 is received thereover. The basic shapes and interconnections between the parts would correspond to those in the embodiment shown in the drawings, except for these stated modifications. This embodiment would again provide the option of either a long or short cannula for use, with the shorter cannula including a sealing ridge as previously described.

As shown in FIG. 15, in this embodiment there is provided a cannula base 16a secured to the syringe body 11. The base includes a tapered outer surface 32a terminating in a ridge 23a for attaching a cover. A sealing ridge 21a surrounds the short cannula 14a and defines therewith an annular recess 22a. The cannula 14a is shown as being relatively short, but it will be appreciated that the cannula could also be relatively long, e.g., of the length shown in FIG. 4.

The teat infusion syringe of the present invention is therefore shown to provide a simple assembly which is readily used for administering materials into the teat canal. The design enhances the junction between the teat orifice and the base of the cannula resulting in a superior seal between the teat canal and the cannula. The invention is suitable to "short" cannula, and to dual or multiple cannula teat infusion syringes, and may also have utility with "long" cannula syringes. The term "short" refers to a cannula which does not completely penetrate the teat canal, which is 7-16 mm long. The term "long" refers to a cannula which passes completely through the teat canal. The superior seal created by the invention minimizes leakage of a product being infused into the udder of an animal. The inventive syringe therefore improves the functionality of the cannula creating a positive stop junction between the base of the cannula and the outer, dorsal surface of the teat, thereby reducing the potential leakage of a product being infused into the quarter.

While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrated and not restrictive in character, it being understood that only the preferred embodiments have been shown and described.

Claims

What is claimed is:

1. A teat infusion cannula cover assembly for reception over a syringe body and associated first cannula, said cover assembly comprising: a cover having a central lumen and an open proximal end for reception therein of the first cannula, the proximal end of said cover further defining attachment means for attachment to at least one of the syringe body and the first cannula, the central lumen defining an end shoulder for sealing engagement of the tip of the first cannula; a second cannula attached to said cover and extending distally therefrom, the second cannula having a lumen communicating with the central lumen of said cover, characterised in that the cover defines: an annular sealing ridge surrounding said second cannula for sealing with a teat when said second cannula is inserted into a teat canal.

2. The cannula cover of claim 1 in which the second cannula is a short cannula.

3. The cannula cover of claim 2 in which the first cannula is a long cannula and the central lumen of said cover is sized to receive and seal with the long, first cannula.

4. A teat infusion syringe which comprises: a syringe body; a first cannula secured to said syringe body; and a cannula cover secured to at least one of said syringe body and said first cannula, said cannula cover including a central lumen and an open proximal end for reception therein of said first cannula, said cannula cover further including a second cannula extending distally therefrom, the second cannula having a lumen communicating with the central lumen of the cannula cover, characterised in that the cannula cover includes an annular sealing ridge surrounding the second cannula for sealing with a teat when the second cannula is inserted into a teat canal.

5. A teat infusion syringe which comprises: a syringe body; a first cannula secured to said syringe body; and a cannula cover secured to at least one of said syringe body and said first cannula, said cannula cover including a central lumen and an open proximal end for reception therein of said first cannula, said cannula cover further including a second cannula extending distally therefrom, the second cannula having a lumen communicating with the central lumen of said cannula cover, characterised in that: at least one of said syringe body and said first cannula defines an annular sealing ridge surrounding said first cannula for sealing with a teat when said first cannula is inserted into a teat canal.

6. The syringe of claims 4 or 5 in which the central lumen defines an end shoulder positioned in sealing engagement with the tip of said first cannula.

7. The syringe of claims 4 or 5 in which said cannula cover includes attachment means for providing a snap fit of said cannula cover to at least one of said syringe body and said first cannula.

8. The syringe of claims 4 or 5 and which further includes an end cap secured to said cannula cover.

9. The syringe of claim 8 in which said end cap includes means for providing a snap fit of said end cap with said cannula cover.

10. The syringe of claim 4 in which said first cannula is a long cannula and the second cannula is a short cannula.

11. The syringe of claim 5 in which said first cannula is a short cannula and the second cannula is a long cannula.