Abstract:
This invention relates to medical devices useful for infusion therapy and, more particularly, to a syringe that can be selectively used with a retractable needle or with frontal attachment devices such as luer hubs, valves or other connectors in needleless systems.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of International Application Number PCT/US2009/059962, filed Oct. 8, 2009 and also claims the benefit of U.S. Provisional Application No. 61/107578, filed Oct. 22, 2008. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    This invention relates to medical devices useful for infusion therapy and, more particularly, to a syringe that can be selectively used with a retractable needle, with a needle attached to a standard luer connector, or with other frontal attachment devices such as hubs, valves or other connectors suitable for use in needleless systems. 
       SUMMARY OF THE INVENTION 
       [0003]    The apparatus of the invention is more widely applicable than known devices because it provides a user with the functionality of both a retractable needle and a needleless connector in a single syringe body. The subject apparatus preferably comprises a barrel, a plunger assembly slidably disposed inside the barrel, a needle retraction assembly and an optional protective guard disposed near the front of the barrel, a retraction cavity disposed inside the plunger assembly, and a closure sealing the forward end of the retraction cavity prior to retraction. When equipped with a needle assembly, which can be attached during manufacture or at the use site as desired, the apparatus can be used, for example, to draw medications from vials, to administer injections, and to infuse medications into IV delivery systems having pierceable ports. 
         [0004]    When used without a needle assembly, the apparatus is also attachable to a frontal attachment device such as a valve (e.g., CLAVE® connector) or luer hub for introducing medication into a closed IV delivery system. When used with a valve, the valve is desirably closed by activating the retraction mechanism prior to disengaging the valve from the syringe. The apparatus also desirably comprises a forwardly extending protective guard structure that helps protect the fluid pathway through the syringe from contamination due to incidental contact with a person or surface. The protective guard structure is preferably outwardly flared to facilitate movement of a needle assembly or other frontal attachment device into a position suitable for attachment to the syringe. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]    The apparatus of the invention is further described and explained in relation to the following drawings wherein: 
           [0006]      FIG. 1  is a rear perspective view of a preferred apparatus of the invention with an attached needle and needle cover; 
           [0007]      FIG. 2  is an exploded front perspective view of the apparatus of  FIG. 1 ; 
           [0008]      FIG. 3  is a cross-sectional elevation view, partially broken away, of the apparatus of  FIG. 1 ; 
           [0009]      FIG. 4  is the cross-sectional elevation view of the apparatus of  FIG. 3  with the needle cover removed; 
           [0010]      FIG. 5  is a cross-sectional elevation view of the apparatus of  FIG. 1  following removal of the needle cover and retraction of the needle into the syringe; 
           [0011]      FIG. 6  is a cross-sectional side view of the plunger handle of  FIG. 2 ; 
           [0012]      FIG. 7  is an enlarged cross-sectional view of the forwardly extending tip of the plunger handle of  FIG. 6 ; 
           [0013]      FIG. 8  is an enlarged plan view of the needle holder of  FIG. 2 ; 
           [0014]      FIG. 9  is a cross-sectional view of the needle holder taken along line  9 - 9  of  FIG. 8 ; 
           [0015]      FIG. 10  is an enlarged cross-sectional view of the syringe barrel of  FIG. 2 ; 
           [0016]      FIG. 11  is an enlarged side view of the needle connector of  FIG. 2 ; 
           [0017]      FIG. 12  is a left end view of the needle connector of  FIG. 11 ; 
           [0018]      FIG. 13  is a cross-sectional view of the needle connector taken along line  13 - 13  of  FIG. 12 ; 
           [0019]      FIG. 14  is an enlarged side view of the needle assembly, comprising the needle connector, needle and needle cover of  FIG. 2 ; 
           [0020]      FIG. 15  is a cross-sectional view of the needle assembly of  FIG. 14 ; 
           [0021]      FIG. 16  is a cross-sectional detail view of the right end portion of the needle assembly of  FIG. 15 ; 
           [0022]      FIG. 17  is a cross-sectional view of the needle cover of  FIG. 15  with the needle connector and needle removed; 
           [0023]      FIG. 18  is a partially exploded side elevation view of a syringe as in  FIG. 1 , but having a frontal attachment that is a luer hub rather than a needle assembly as shown, for example, in  FIGS. 2-4 ; 
           [0024]      FIG. 19  is an enlarged cross-sectional view of the apparatus of  FIG. 18 , but showing the luer hub connected to the syringe; 
           [0025]      FIG. 20  is a partially exploded side elevation view, partially broken away of a syringe as in  FIG. 1 , but having a frontal attachment that comprises a valve; and 
           [0026]      FIG. 21  is an enlarged cross-sectional view of the apparatus of  FIG. 20 , but showing the frontal attachment connected to the syringe. 
       
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0027]    Referring to  FIG. 1 , a preferred apparatus  20  of the invention is disclosed that comprises syringe  22  in combination with a frontal attachment that is needle assembly  24 . Referring to  FIG. 1  in combination with  FIG. 2 , an exploded view, syringe  22  of apparatus  20  preferably comprises a plunger assembly further comprising plunger handle  28 , rear plug  26 , front plug  30 , and plunger seal  32 . A retraction cavity is also disposed inside plunger handle  28  between front plug  30  and rear plug  26 , and a portion of barrel  40  of syringe  22  can also serve as part of the retraction cavity. A vent  23  is desirably disposed near the rear of the plunger handle. 
         [0028]    Syringe  22  also preferably comprises a retraction assembly further comprising needle holder  36 , retainer member  34 , and retraction spring  38 . Retainer member  34  is preferably attachable to needle holder  36 , and needle holder  36  is preferably partially insertable into spring  38 . During the manufacture of syringe  22 , the retraction assembly is preferably installed into barrel  40 , and the plunger assembly is thereafter installed into barrel  40  behind the retraction assembly. 
         [0029]    The needle assembly preferably comprises needle connector  42 , needle  44  and needle cover  46 . Needle  44  is preferably secured in fixed relation to needle connector  42 , and the opposite end of needle connector  42  desirably threads into the cooperatively threaded forwardly extending portion of needle holder  36 , as described below in relation to  FIGS. 3 and 4 . Apparatus  20  can be manufactured in this form if desired, or the needle assembly can be packaged and sold separately, and attached to syringe  22  at the use site. 
         [0030]    Referring to  FIGS. 3 and 4 , retainer member  34  is preferably a separate, elastomeric member but can also be unitarily molded or otherwise formed as part of needle holder  36  to provide a fluid seal between it, needle holder  36  and barrel  40  and thereby establish a fluid chamber between needle the retraction assembly and plunger seal  32 , and also hold spring  38  in compression by engagement with barrel  40 . According to a particularly preferred embodiment of the invention, needle holder  36  comprises a slot or other structure that is engageable with a portion of barrel  40  to resist relative rotation between the needle holder and barrel, especially during attachment of the needle assembly or other frontal attachment to the syringe to form apparatus  20 . The outside of needle cover  46  preferably slides inside of female threads  54  to permit threaded engagement between needle connector  42 , to which needle  44  is attached in fixed relation by gluing or another similarly effective known method, and the cooperatively threaded portion of needle holder  36 . The internal bore of needle  44  is thereby placed in fluid communication with internal bore  48  of needle holder  36  and with the fluid chamber behind needle holder  36  inside barrel  40 . Front plug  30  inside the forwardly extending portion of plunger handle  28  prevents any fluid disposed inside the syringe from entering the portion of the retraction cavity inside the plunger handle prior to the time that front plug  30  is displaced rearwardly when retraction is initiated by the user. Elements of the protective guard structure  52  are desirably inclined outwardly relative to barrel  40  to reduce the likelihood of contaminating the forwardly extending tip of needle holder  36  prior to or during connection of the frontal attachment, in this case the needle assembly comprising needle cover  46 , needle  40  and needle connector  42 . The inclined elements of the protective guard structure  52  also assist in guiding the frontal attachment into alignment with the front of needle holder  36 . Following attachment of needle connector  42  to needle holder  36 , and just prior to use, needle cover  46  is desirably removed from frictional engagement with needle connector  42  as depicted in  FIG. 4 . 
         [0031]    Referring to  FIG. 5 , following the infusion of fluid through syringe  22 , needle connector  42  and needle  44 , retraction of needle  44  is initiated by forcing plunger handle  28  forward relatively to barrel  40 , thereby causing the front portion of front plug  30  to contact the rearwardly facing portion of needle holder  36 . When this occurs, front plug  30  is displaced rearwardly and the forwardly extending tip of plunger handle  28  contacts and pushes retainer member  34  forwardly into annular recess  50 , thereby disengaging retainer member  34  from needle holder  36  and allowing compressed spring  38  to force needle holder  36 , needle connector  42  and needle  44  upwardly into syringe  22  to a position where the front tip of needle  44  no longer protrudes from the front of barrel  40  to a position where it could cause an accidental needlestick. When plunger handle  28  abuts against the inside of barrel  40 , the pressure exerted against rear plug  26  by the hand of the user while simultaneously exerting an opposed finger force against the forwardly facing surface of radially extending flange member  64  desirably causes the peripheral member  66  around the back of plunger handle  28  to be forced into a recessed position inside the back opening of collar  62 . As needle holder  36  moves rearwardly due to the force of spring  38 , front plug  30  is also forced upwardly into the cavity inside plunger handle  28 , and air inside the cavity can escape through vent  23 . 
         [0032]    Other portions of the preferred apparatus disclosed in relation to  FIGS. 1-5  are further shown, described and explained in relation to  FIGS. 6-17 .  FIG. 6  discloses plunger handle  28 , retraction cavity  70  inside plunger handle  28 , and a forwardly extending tip of plunger handle  28  that further comprises an annular projection  42  that cooperates with shoulder  76  to define a recess  74  into which plunger seal  32  described above can be seated to provide a fluid seal against the inside of the syringe barrel. Arrow  78  indicates the open front end of plunger handle  78  in which front plug  30  of  FIG. 2  is seated during assembly. Referring to  FIG. 7 , a detail view is shown that better depicts the stepped front end of plunger handle  28  in which surface  80  projects forwardly to a greater extent than surface  82 . Such a step is preferred for concentrating the retraction force applied through the plunger handle against one side of retainer member  34  prior to the other side, thereby assisting in the removal of retainer member  34  from needle holder  36 . 
         [0033]      FIG. 8  further depicts cylindrical head  84 , split annular shoulder  86 , slot  90 , slot walls  88 ,  92 , and tapered outside luer surface  58  of needle holder  36 . The rear of spring  38 , discussed above, abuts against shoulder  86 , and the outer diameter of the forwardly extending portion of needle holder  36  is desirably slightly less than the inside diameter of compressed spring  38  to allow the coils of spring  38  to encircle the forwardly extending part of the needle holder. Referring to  FIG. 9 , female threads  92  inside the portion comprising luer surface  58  are desirably cooperatively sized and aligned to receive the corresponding male threads of needle connector  42 , described above, into engagement therewith. Tapered surface  100  desirably slidably engages surface  112  of needle connector  42 , described in relation to  FIGS. 11 and 12  below, and passageways  94 ,  96  and  98  cooperate to establish a fluid flow path through needle holder  36 . 
         [0034]      FIG. 10  further discloses rear opening  60 , annular collar  62 , grippable finger flanges  64 , female threads  54  and forwardly and outwardly projecting elements of the protective guard structure  52 . 
         [0035]      FIGS. 11-13  further disclose circumferentially disposed ribs  108  around the front portion of needle connector  42 , centrally disposed bore  106  establishing a fluid pathway through the connector, male threads  110 , and tapered guiding and engagement surface  112 . 
         [0036]      FIGS. 14-17  further disclose rear end  116  and rear opening  122 , forwardly extending tapered outside wall section  114 , and closed end  115  of needle cover  46 . Prior to attachment of needle connector  42  to syringe  22 , discussed above, the rear end of needle  44  is desirably inserted into elongate cavity  118  of needle cover  46 , and is glued or otherwise attached in fixed relation to needle connector  42  inside bore  106 . Needle connector  42  desirably frictionally engages the inside wall of section  116  of needle cover  46  in such manner that the free end of needle connector  42  resides inside substantially cylindrical space  120 , most preferably packaged inside a sterile wrapper if provided as a separate assembly, until the time when needle connector  42  is threaded into the needle holder of a syringe as described above. 
         [0037]      FIGS. 18-19  disclose a frontal attachment  126  comprising luer hub  132 , luer locking flange  134 , needle  136  and finger grips  128 ,  140  for use in threading the luer hub into sealing engagement with female threads  54  inside the front portion of barrel  40  of syringe  122 , behind protective guard structure  52 . Grippable surface ridges  130  are also desirably provided on syringe  22  to facilitate gripping during connection of the frontal attachment. Internal cavity  138  of frontal attachment  126  provides fluid communication between needle  136  and cavity  98  inside needle connector  42  as discussed above. Although the retraction assembly comprising retainer member  34 , needle holder  36  and spring  38  are still in place, needle  136  cannot be retracted inside syringe  22  in this embodiment, and must be recovered or, more preferably, disposed in an approved sharps disposal container. 
         [0038]      FIGS. 20-21  disclose a frontal attachment  142  that is a valve assembly having external threads  144  that is also attachable to female threads  54  behind protective guard structure  52  of barrel  40 . In this embodiment, there is no needle to be retracted following use. 
         [0039]    Other alterations and modifications of the invention will likewise become apparent to those of ordinary skill in the art upon reading this specification in view of the accompanying drawings, and it is intended that the scope of the invention disclosed herein be limited only by the broadest interpretation of the appended claims to which the inventor is legally entitled.