Abstract:
A safety assembly includes a holder with a proximal end, a distal end and a tubular sidewall extending between the ends. The proximal end is configured to engage a needle assembly. The distal end is configured to slidably receive a fluid collection tube. A shield is hingedly mounted to the distal end of the holder and can rotate from a first position where the shield lies adjacent the holder to a second position where the needle is shielded. A spring is disposed for biasing the shield to the second position. A latch is disposed on the holder for movement between a locking position where the latch holds the shield in the first position and a release position where the latch permits the shield to be propelled to the second position.

Description:
RELATED APPLICATIONS  
       [0001]    This application claims priority on U.S. Provisional Patent Appl. No. 60/366,368 filed Mar. 20, 2002. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The present invention relates to a shield for a needle and more particularly to a safety shield that may be used in conjunction with a needle assembly and a needle holder.  
         BACKGROUND OF THE INVENTION  
         [0003]    Disposable medical devices having piercing elements for administering a medication or withdrawing a fluid, such as hypodermic needles, blood collecting needles, fluid handling needles and assemblies thereof, require safe and convenient handling. The piercing elements include, for example, pointed needle cannula or blunt ended cannula.  
           [0004]    Safe and convenient handling of disposable medical devices is recognized by those in the medical arts so as to minimize exposure to blood borne pathogens. Safe and convenient handling of disposable medical devices results in the disposal of the medical devices intact.  
           [0005]    As a result of this recognition, numerous devices have been developed for shielding needles after use. Many of these devices are somewhat complex and costly. In addition, many of these devices are cumbersome to use in performing procedures. Furthermore, some of the devices are so specific that they preclude use of the device in certain procedures or with certain devices and/or assemblies.  
           [0006]    Therefore, there exists a need for a safety shield assembly: (i) that is manufactured easily; (ii) that is applicable to many devices; (iii) that is simple to use with one hand; (iv) that can be disposed of safely; (v) that does not interfere with normal practices of needle use; (vi) that has tactile features whereby the user may be deterred from contacting the needle, the user may easily orient the needle with the patient and easily actuate and engage the shield assembly; (vii) that has visual features whereby the user may be deterred from contacting the needle, the user may easily orient the needle with the patient and easily actuate and engage the shield assembly; (viii) that is not bulky; (ix) that includes means for minimizing exposure to the user of residual fluid leaking from the needle; and (x) provides minimal exposure to the user because the needle shield is immediately initiated by the user after. the needle is withdrawn from the patient&#39;s vein.  
         SUMMARY OF THE INVENTION  
         [0007]    The present invention is a safety shield assembly that comprises: a shield; means for connecting the shield to a fluid handling device that contains a piercing element, such as needle; means for securely covering and/or containing the needle within the shield and means for securely locking the shield in a final non-retractable closed position over the needle.  
           [0008]    Preferably, the shield comprises a rearward end, a forward end, a slot or longitudinal opening for housing the used needle in the forward end, means for securing the needle in the slot, means for guiding the needle into the slot, means for connecting the shield and the fluid handling device, means for guiding the user&#39;s fingers to move the shield into various positions, and means for retaining the shield securely over the used needle.  
           [0009]    The shield may be connected to the fluid handling device by a hanger bar that engages with a hook arm on the fluid handling device so that the shield may be pivoted with respect to the fluid handling device into several positions. It is within the purview of the present invention to include any structure for connecting the shield to the fluid handling device so that the shield may be pivoted with respect to the fluid handling device. These structures include known mechanical hinges and various linkages, living hinges, or combinations of hinges and linkages.  
           [0010]    The shield may be connected to the fluid handling device by an interference fit between the hanger bar and the hook arm. Therefore, the shield always is oriented in a stable position and will not move forward or backwards unless movement of the shield relative to the hanger bar and the hook bar is initiated by the user.  
           [0011]    Alternatively, the shield and fluid handling device may be a unitary one-piece structure. The one-piece structure may be obtained by many methods, including molding the shield and the fluid handling device as a one-piece unit, thereby eliminating the separate shield and the fluid handling device during the manufacturing assembly process.  
           [0012]    The assembly of the present invention may further comprise tactile and visual means for deterring the user from contacting the needle, providing easy orientation of the needle with the patient and providing the user with a guide for actuation and engagement with the shield.  
           [0013]    The assembly of the present invention may further comprise means for minimizing exposure by the user to residual fluid leaking from a used needle. For example, a polymer material, such as a gel, may be located in the shield.  
           [0014]    Most desirably, the assembly of the present invention is such that the cooperating parts of the assembly provide the means for the shield to move into a forward position over the needle. Thus, by simple movement of the shield into a forward position over the used needle, the assembly is ready for subsequent disposal. Therefore, the safety shield assembly of the present invention provides minimal exposure of the user to a needle because the shielding is initiated by the user immediately after the needle is withdrawn from the patient&#39;s vein.  
           [0015]    Desirably, the assembly of the present invention may be used with a syringe assembly, a hypodermic needle, a needle assembly, a needle assembly with a needle holder, a blood collection set, an intravenous infusion set or other fluid handling devices. Preferably, the assembly of the present invention is used with a needle assembly comprising a needle and a hub. Preferably the needle is a conventional double ended needle.  
           [0016]    Most preferably, the present invention is used with a needle assembly comprising a hub and a needle connected to the hub whereby the needle comprises a non-patient end and an intravenous end. The fluid handling device of the present invention may comprise a hook arm and the shield may be connected movably to the hook arm. Thus the shield may be position with respect to the fluid handling device and moved easily into several positions.  
           [0017]    Preferably, the fluid handling device is fitted non-rotatably with the hub of the needle assembly. Additionally, the fluid handling device includes cooperating means that mate with reciprocal means on the shield to help retain the shield in a final closed position, to propel the shield toward the final closed portion and to provide a clear audible and tactile indication of complete shielding.  
           [0018]    The shield preferably includes a cannula finger lock for locked engagement with the cannula when the shield is in the final closed position around the needle cannula. The cannula finger lock preferably projects obliquely from one sidewall of the shield angularly toward the opposed sidewall and the top wall of the shield. The cannula finger lock is dimensioned, disposed and aligned to contact the needle cannula when the shield approaches the final closed position. Contact between the cannula and the cannula finger lock will cause the cannula finger lock to resiliently deflect toward the sidewall from which the cannula finger lock extends. Sufficient rotation of the shield will cause the needle cannula to pass the cannula finger lock. As a result, the cannula finger lock will resiliently return to or toward its undeflected condition for securely trapping the needle cannula in the shield.  
           [0019]    Preferably, the fluid handling device is fitted with the hub of the needle assembly so that the fluid handling device cannot rotate around the hub. Additionally, the fluid handling device includes cooperating means that mate with reciprocal means on the shield to propel the shield toward a final closed position.  
           [0020]    Alternatively, the fluid handling device and hub may be a unitary one-piece structure. The one piece structure may be accomplished by many methods including molding the fluid handling device and the hub as a one-piece unit thereby eliminating the need to separately assemble the fluid handling device to the hub during the manufacturing process.  
           [0021]    Most preferably, the fluid handling device is fitted with the hub of the needle assembly so that the bevel surface or bevel up surface of the intravenous or distal end of the needle faces the same side of the fluid handling device when the shield is in the open position. Alignment of the fluid handling device, hub, shield and needle with the bevel surface up makes it easier to insert the needle into the patient without manipulating the assembly. The orientation of the intravenous end of the needle with the bevel up assures the user that the needle is oriented properly for use and does not require any manipulation before use. Most notably, the orientation of the shield provides a visual indication to the user of the orientation of the bevel surface of the needle.  
           [0022]    Alternatively, it is within the purview of the present invention that the shield, fluid handling device and hub is a unitary one-piece structure. The one-piece structure may be accomplished by many methods including molding the shield, fluid handling device and hub as a one piece unit thereby eliminating the need to separately assemble the shield, fluid handling device and hub during the manufacturing process.  
           [0023]    Another notable attribute of the present invention is that the tactile and visual features deter the user from touching the needle, allow the user to easily orient the needle with the patient and guide the user to actuate and engage the shield of the assembly. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0024]    [0024]FIG. 1 is an exploded perspective view of a shield, needle holder and needle assembly in accordance with the first embodiment of the invention.  
         [0025]    [0025]FIG. 2 is an exploded perspective view of a prior art needle assembly for use with the holder of FIG. 1.  
         [0026]    [0026]FIG. 3 is a longitudinal cross-sectional view showing the shield in the open condition with the needle cannula in the exposed ready-to-use position.  
         [0027]    [0027]FIG. 4 is a cross-sectional view similar to FIG. 3, but showing the shield in the shielded position.  
         [0028]    [0028]FIG. 5 is a cross sectional view similar to FIG. 3, but showing a second embodiment with a rotatable flange for releasing the shield.  
         [0029]    [0029]FIG. 6 is an end elevational view of the embodiments shown in FIG. 5.  
         [0030]    [0030]FIG. 7 is a perspective view similar to FIG. 1, showing a third embodiment with a rotatable lock for holding the shield in the open condition.  
         [0031]    [0031]FIG. 8 is a cross-sectional view taken along line  8 - 8  in FIG. 7.  
         [0032]    [0032]FIG. 9 is a perspective view similar to FIG. 7, but showing a fourth embodiment of a lock for holding the shield in the open position.  
         [0033]    [0033]FIG. 1O is a perspective view of a fifth embodiment. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0034]    While this invention is satisfied by embodiments in many different forms, there is shown in the drawings and will herein be described in detail, the preferred embodiments of the invention, with the understanding that the present disclosure is to be considered as exemplary of the principles of the invention and is not intended to limit the invention to the embodiments illustrated. Various other modifications will be apparent to and readily made by those skilled in the art without departing from the scope and spirit of the invention. The scope of the invention will be measured by the appended claims and their equivalents.  
         [0035]    A holder in accordance with the subject invention is identified generally by the numeral  10  in FIG. 1. Holder  10  preferably is formed unitarily from a plastic material and includes a tubular side wall  12  with a proximal end  14  and a distal end  16 . Proximal end  14  of tubular side wall  12  is widely open and is dimensioned to slidably accommodate an evacuated blood collection tube (not shown). A flange  18  projects outwardly at proximal end  14  of tubular side wall  12  to facilitate gripping and manipulation of holder  10 .  
         [0036]    An annular distal end wall  20  extends inwardly at distal end  16  of tubular side wall  12 . A central aperture  22  extends through distal end wall  20  and communicates with internal portions of holder  10 . Holder  10  is further characterized by an internally threaded cylindrical collar  24  formed concentrically with aperture  22 . Additionally, hook arms  26  extend distally from distal end wall  20 .  
         [0037]    Holder  10  is employed with a known needle assembly  28 . Needle assembly  28  includes a needle  30  with a non-patient end  32 , an intravenous end  34  and a passageway  36  extending between the non-patient end and the intravenous end. An elastomeric sleeve  38  covers the non-patient end. A first rigid sleeve  40  covers the intravenous end and a second rigid sleeve  42  covers the non-patient end and the elastomeric sleeve, as shown in FIG. 2.  
         [0038]    Needle assembly  28  further includes a hub  50  with a threaded end  54 , a ribbed end  56  and a passageway extending between the threaded end and the ribbed end. Threaded end  54  and ribbed end  56  are separated by a flange  58 . Non-patient end  32  of needle  30  extends from threaded end  54 , and intravenous end  34  of needle  30  extends from ribbed end  56 . Threaded end  54  comprises male threads for mounting of  50  in internally threaded collar  24  of holder  10 . In the mounted condition, non-patient end  32  of needle  30  projects into the area bounded by cylindrical side wall  12  of holder  10 .  
         [0039]    Holder assembly  10  further includes a shield  60  that is formed unitarily from a substantially rigid plastic. Shield  60  includes an elongate base wall  64 , opposed side walls  66  and  68  that project from opposite sides of base wall  64  and an end wall  70  that extends from base wall  64  and between side walls  66  and  68 . Hanger bar  72  projects from an end of shield  60  opposite end wall  70  and is rotatably mounted to hook arms  26 . Thus, shield  60  can be rotated about hook arms  26  from an open position as shown in FIGS. 1 and 3 to a closed position as shown in FIG. 4. Shield  60  is dimensioned such that end wall  70  is substantially adjacent flange  18  of holder  10  when shield  60  is in the open position of FIGS. 1 and 3. Additionally, shield  60  is dimensioned such that end wall  70  is disposed distally of needle  30  when shield  60  is rotated to the closed position of FIG. 4. Side walls  66  and  68  of shield  60  are spaced from one another by a distance that exceeds the width of needle  30 . Furthermore, side walls  66  and  68  and end wall  70  project sufficiently from base wall  64  to completely surround needle  30 .  
         [0040]    Shield  60  is formed with needle locks  74  that project from side wall  68  angularly toward base wall  64 . Locks  74  are disposed and configured to contact needle  30  as shield  60  is rotated into the closed position. This contact will cause locks  74  to resiliently deflect. However, locks  74  will return to an undeflected condition and trap needle  30  after shield  60  reaches the closed position of FIG. 4.  
         [0041]    Holder assembly  10  further includes a spring  76  mounted to or near hook arms  26 . In the preferred embodiment, spring  76  is a torsion spring having a first leg  78  biased against an external surface of holder  10  and a second leg  80  biased against a surface of shield  60 . Legs  78  and  80  are biased into a stored-energy position when shield  60  is in the open position of FIGS. 1 and 3. However, spring  76  is configured and disposed to bias shield  60  completely to the closed position of FIG. 4. The torsion spring, illustrated in FIGS.  1 - 4 , can be replaced by a leaf spring mounted at substantially the same location on holder  10 . Alternatively, the shield can be joined unitarily to holder  10  by an over-center living hinge. Over-center hinges on a shield are shown, for example, in U.S. Pat. No. 5,242,417.  
         [0042]    Shield  60  is retained releasably in the open position and against the forces of spring  76  by a latch  82 . Latch  82  protects unitarily from flange  18  and releasably engages an edge of end wall  70  of shield  62  spaced from base wall  64 . Latch  82  is dimensioned and configured to be resiliently deflectable relative to flange  18  and includes an actuator tab  84  dimensioned and configured for convenient digital manipulation.  
         [0043]    Holder  10  may be used substantially in a conventional manner to draw samples of blood or other bodily fluid from a patient. In particular, second rigid sleeve  42  is separated from needle assembly  28  to expose elastomeric sleeve  38 . Threaded end  54  of hub  50  then is engaged threadedly in aperture  24  of holder  10 . First rigid sleeve  40  then can be removed from hub  50  to expose intravenous end  34  of needle  30 . Intravenous end  34  of needle  30  then can be placed in communication with a blood vessel or other source of fluid and an evacuated tube can be urged into open proximal end  14  of side wall  12 . Non-patient end  42  of needle  40  thus is placed in communication with the evacuated tube for collecting specimens of blood or other bodily fluid. A plurality of evacuated tubes may be inserted sequentially into holder  10 . After a sufficient volume of fluid has been collected, intravenous end  34  of needle  30  is removed from the patient. The health care worker then deflects latch  82  sufficiently to separate latch  82  from shield  60 . As a result, spring  76  propels shield  60  from the open position shown in FIGS. 1 and 3 to the closed position shown in FIG. 4. Needle locks  74  engage needle  30  as shield  60  is rotated into its closed position.  
         [0044]    Latch  76  illustrated in FIGS. 1, 3 and  4  is just one of several optional latch configurations. In this regard, a second embodiment of the needle holder  90  is illustrated in FIGS. 5 and 6 and is substantially identical to the first embodiment of FIGS. 1, 3 and  4 . However, holder  90  includes a rotatable flange  92  mounted to proximal end  14  of side wall  12 . A latch  94  projects rigidly and substantially non-deflectably from flange  92 . As a result, latch  94  can be separated from shield  60  merely by rotating flange  92  about proximal end  14  of side wall  12  from a first position where latch  94  engages shield  62  to a second position where latch  94  is rotatably spaced from shield  62 , as shown in broken lines in FIG. 6. Thus, shield  60  will be propelled to the closed position by spring  76  after latch  94  is rotated away from shield  60 .  
         [0045]    A third embodiment is illustrated in FIGS. 7 and 8, and includes a substantially C-shaped latch  100  rotatably mounted on the exterior of cylindrical side wall  12  of holder  10  at a location adjacent flange  18 . In this embodiment, side wall  66  of shield  60  is formed with a slot  102  adjacent base wall  64  for receiving an end of C-shaped latch  100 . Thus, C-shaped latch  100  can be rotated in the direction of the arrow shown in FIGS. 7 and 8 about the axis of holder  10  from a first position where latch  100  engages in aperture  102  of side wall  68  to a second position where latch  100  is spaced from shield  60 . Thus, shield  60  will be propelled into the closed position when C-shaped latch  100  is spaced from aperture  102  in side wall  68  of shield  60 .  
         [0046]    A fourth embodiment is illustrated in FIG. 9 and includes a C-shaped latch  110  that is axially slidable on the exterior of side wall  12  of holder  10 . In a first range of axial movement, latch  110  engages a flange  112  that projects transversely from base wall  64  of shield  60 . Thus, latch  110  prevents shield  60  from being propelled into the closed position. However, a distal movement of latch  110  relative to shield  60 , as shown by the arrow in FIG. 9, separates latch  110  from shield  60  and enables shield  60  to be propelled into the closed position shown in FIG. 4.  
         [0047]    A fifth embodiment is illustrated in FIG. 9 and includes a latch  120  that projects transversely outwardly from a portion of tubular side wall  12  of holder  10  adjacent flange  18 . Latch  120 , however, is disposed and configured to be deflected in the directions of the arrow in FIG. 10 about an axis that extends substantially parallel to the axis of holder  10 . In other respects, however, latch  120  is functionally similar to latch  80  described above and illustrated in FIGS. 1, 3 and  4 .  
         [0048]    While the invention has been described with respect to certain preferred embodiments, it is apparent that variations can be made without departing from the scope of the invention as defined above. For example, the shield can be locked in the closed position by engagement means formed on the shield and on distal portions of the holder or on the needle hub. These locking means on the shield and on the holder or hub can be used in place of cannula latches or in addition to the above-described cannula latches.