Abstract:
A venous access device is generally discussed herein with particular discussions extended to port access device having a protective clip. The port access device includes a needle hub having a needle extending therefrom and a catheter hub having a catheter tube extending therefrom with the needle positioned inside the tube in a ready to use position. A tip protector is positioned inside a clip housing, which is positioned in between the catheter hub and the needle hub.

Description:
[0001]     A venous access device is generally discussed herein with particular discussions extended to port access device having a protective clip.  
       BACKGROUND  
       [0002]     Venous access to a patient&#39;s venous system may be accomplished using a peripheral intravenous catheter (PIC) in some instances and a central venous catheter (CVC) in other instances, which are well known in the health care industry. For long term venous access, a subcutaneous implantable port (sometimes referred to only as “port”) is preferred. An implantable port generally comprises an injection port housing, typically made from an exotic metal such as titanium, and a catheter implanted under the skin with a catheter connected.  
         [0003]     To access a patient&#39;s venous system, a Huber needle is typically used to puncture through the injection port housing, and obviously through the skin. Once completed, the injection port housing reseals itself. It is not uncommon to be able to access the injection port housing hundreds of times before having to replace it. It is also not uncommon to leave a Huber needle in the injection port housing for extended time periods, in the order of several days, without increased complications. However, the longer the needle remains in the port, the more difficult it is to remove. It is well documented that this resistance to removal causes a rebound affect when the needle is withdrawn from the port thus resulting in possible needle sticks to the clinician. In addition, the rigid needle remains in a layer of tissue directly above the port resulting in discomfort to the patient.  
         [0004]     More recently, the use of a polymer, such as a polyurethane catheter, to access the injection port housing is preferred as it increases the intervals between having to remove the device from the injection port housing, and hence the number of punctures through the same housing for venous access. It would be desirable to use a plastic catheter over a needle for port access. That way, the needle can be withdrawn immediately after insertion leaving only the plastic catheter in place. The flexible (or semi-rigid) catheter would provide more comfort to the patient and be easier to remove. It would also be desirable to provide a safety shield to protect the needle point after removal to prevent inadvertent sticks.  
       SUMMARY  
       [0005]     The present invention may be implemented by providing an access port device comprising a catheter hub comprising a catheter tube extending therefrom, a needle hub comprising a needle having a needle tip extending through the catheter tube, and a housing disposed between the needle hub and the catheter hub; the housing being engaged to the catheter hub so that when the needle hub is rotated relative to the housing, the housing remains fixed to the catheter hub.  
         [0006]     In another aspect of the present invention, there is provided an access port device comprising a catheter hub comprising a catheter tube extending therefrom, a needle hub comprising a needle having a needle tip extending through the catheter tube and beyond a distal end of the catheter tube, a housing disposed between the needle hub and the catheter hub, and a tip protector for covering the needle tip positioned inside a cavity defined by the housing; wherein the housing is threadedly engaged to the needle hub.  
         [0007]     In yet another aspect of the present invention, there is provided An access port device comprising a catheter hub comprising a catheter tube extending therefrom, a needle hub comprising a needle having a needle tip extending through the catheter tube and beyond a distal opening of the catheter tube, a housing disposed between the needle hub and the catheter hub, and a tip protector for covering the needle tip positioned inside a cavity defined by the housing; wherein the catheter hub further comprises a flow chamber in fluid communication with the catheter tube.  
         [0008]     Other aspects of the present invention includes provisions for controllably rotating a needle hub a desired rotation and moving a needle an axial length relative to a catheter tube.  
         [0009]     In yet other aspects of the present invention, an access port device is provided whereby a pair of wing flaps extend radially outwardly from a catheter hub for resting against a patient&#39;s skin.  
         [0010]     In other aspects of the present invention, an access port device is provided in which a needle is a solid metallic stylus.  
         [0011]     In yet another aspect of the present invention, an access port device is provided in which a septum is incorporated in a catheter hub for occluding a needle port through the hub.  
         [0012]     These and other features and advantages of the present invention will become appreciated as the same become better understood with reference to the specification, claims and appended drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]     The drawings appended herein include:  
         [0014]      FIG. 1  is a semi-schematic exploded side view of a port access device provided in accordance with aspects of the present invention;  
         [0015]      FIG. 2  is a semi-schematic cross-sectional side view of the device of  FIG. 1  taken along line  2 - 2 ;  
         [0016]      FIG. 3  is a semi-schematic cross-sectional side view of the device of  FIG. 1  in a ready to use-position;  
         [0017]      FIG. 4  is an enlarged cross-sectional view of the needle tip of  FIG. 3 ;  
         [0018]      FIG. 5  is a semi-schematic cross-sectional side view of the device of  FIG. 3  with the needle hub rotated relative to the catheter hub; and  
         [0019]      FIG. 6  is an enlarged cross-sectional side view of the needle tip of  FIG. 5 . 
     
    
     DETAILED DESCRIPTION  
       [0020]     The detailed description set forth below in connection with the appended drawings is intended as a description of the presently preferred embodiments of a port access device provided in accordance with aspects of the present invention and is not intended to represent the only forms in which the present invention may be constructed or utilized. The description sets forth the features and the steps for constructing and using various embodiments of the port access device of the present invention in connection with the illustrated embodiments. It is to be understood, however, that the same or equivalent functions and structures may be accomplished by different embodiments that are also intended to be encompassed within the spirit and scope of the invention. As denoted elsewhere herein, like element numbers are intended to indicate like or similar elements or features.  
         [0021]     Referring now to  FIG. 1 , a semi-schematic exploded side view of a port access device provided in accordance with aspects of the present invention is shown, which is generally designated  10 . In one exemplary embodiment, the port access device  10  comprises a winged catheter  12 , which comprises a catheter tube  14  attached to and extending from a catheter hub  16 , and a needle assembly  18 , which comprises a needle  20  attached to and extending from a needle hub  22 . In use, the needle assembly  18  is normally coupled to the winged catheter  12  with the needle  20  projecting through the catheter tube  14  and the tip of the needle exposed through the distal end opening  24  of the catheter tube.  
         [0022]     In one exemplary embodiment, a housing  26  comprising a central opening  28  ( FIG. 2 ) is incorporated and positioned between the winged catheter  12  and the needle assembly  18 . The housing  26  is configured to house a protective clip for covering the tip of the needle after the needle is withdrawn from an injection port housing. As further discussed below, the housing  26  is also configured to lock from rotating against the catheter hub  16  and jack the needle hub  22  a controlled distance relative to the catheter hub  16  to create a flow path for blood flashback.  
         [0023]     In one exemplary embodiment, the housing  26  comprises a housing top  30  comprising a plurality of threads  32 , a body section  34 , and a skirt section  36 . The housing top  30  is configured to threadedly couple to a corresponding threaded female bore located on the needle hub  22 . The threads are sized and angled so as to produce a desired lead when the needle hub  22  is rotated an arc degree relative to the housing, as further discussed below.  
         [0024]     In one exemplary embodiment, the skirt section  36  comprises a plurality of downwardly extending teeth  38 . The teeth  38  are preferably formed around the lower periphery of the body section  34 . More preferably, the teeth are formed around about half of the lower periphery of the body section  34  to facilitate grabbing an upper edge of the catheter hub  16 , as further discussed below. The teeth  38  are configured to interact with the upper edge of the catheter hub  16  to prevent the housing  26  from rotating relative to the catheter hub  16 .  
         [0025]     In one exemplary embodiment, the catheter hub  16  comprises an upper hub block  40  coupled to a lower hub block  42 . In one application of the invention, the two hub blocks  40 ,  42  are bonded together along a seam  44 , using high frequency welding or adhesive. As further discussed below, a septum and an attachment wing are preferably wedged in between the two blocks  40 ,  42  prior to bonding the two.  
         [0026]     In one exemplary embodiment, a low profile attachment wing  46  comprising two wing flaps  48  attached to one another at a bridge  50  is incorporated. The two wing flaps  48  extend radially outwardly from the catheter hub  16  and in one exemplary embodiment lie generally on a same plane. The two wing flaps  48  may incorporate different shapes but are preferably both generally rectangular in configuration. In one exemplary embodiment, a plurality of raised bumps  52  are incorporated on an underside surface  54  of each wing flap  48 . When incorporated, the raised bumps  52  allow a patient&#39;s skin to breath by providing gaps between the underside surfaces  54  of the wing flaps  48  and the skin.  
         [0027]     In one exemplary embodiment, a plurality of male detents  56  are incorporated in the catheter hub  16 . More specifically, in one exemplary embodiment, a plurality of undercuts  58  are formed on the upper hub block  40  along a lower section of the hub block, near the seam  44 . The detents  56  are formed above the undercuts  58  due to the voids provided in forming the undercuts  58 . As further discussed below, the combination male detents  56  and undercuts  58  are configured to interact with the teeth  38  on the clip housing  26  to inhibit relative movement between the two. In a preferred embodiment, three detents  56  and three undercuts  58  are incorporated.  
         [0028]     Referring now to  FIG. 2 , a semi-schematic cross-sectional side view of the port access device of  FIG. 1  is shown, taken along line  2 - 2 . In one exemplary embodiment, the needle hub  22  incorporates a generally cylindrical bore  60  defining a cavity and having a recessed boss  62  comprising corresponding threads for mating with the threads  32  on the housing top  30  of the clip housing  26 . The cylindrical bore  60  is sized to receive the clip housing  26  having a protective clip disposed therein, as further discussed below.  
         [0029]     In one exemplary embodiment, the needle hub  22  comprises a base  66  comprising a base surface and a projection  64  that extends outwardly from the base surface. The projection  64  defines a gap  65  or elevation difference between the base surface  68  of the projection  64  and the base surface of the base  66 . In one exemplary embodiment, the gap  65  comprises a dimension that approximately equals a height of a flange located on the clip housing  26 , as further discussed below.  
         [0030]     In one exemplary embodiment, the needle  20  is molded into the needle hub  22 . More preferably, the needle is positioned centrally of the bore  60  when molded into the hub  22 . Alternatively, a bore having a well may be incorporated into the hub and the needle  20  attached thereto using curable glue or adhesive. In one exemplary embodiment, the needle  20  comprises a 12 gauge to a 26 gauge solid metallic stylus. More preferably, the needle  20  is solid and incorporates a non-coring needle tip. In a preferred embodiment, the needle tip comprises a Trocar-type needle tip. Alternatively, a Huber-type bevel needle tip or a pencil point needle may be incorporated.  
         [0031]     In one exemplary embodiment, a clip or needle tip protector  70  is incorporated for blocking the needle tip following a needle puncture. In one exemplary embodiment, the clip  70  is one of the types disclosed in patent application Ser. No. 10/734,931, filed Dec. 12, 2003, entitled SPRING CLIP SAFETY IV CATHETER, the contents of which are expressly incorporated herein by reference. Alternatively, the clip may be one of the types that cant over so that an opening located on the clip grips the needle when activated. Exemplary clips of the latter type are disclosed in U.S. Pat. Nos. 5,611,781, 6,406,459, and 6,709,419 and in application Ser. Nos. 10/905,884, filed Jan. 25, 2005; Ser. No. 10/450,809, filed Dec. 5, 2001; and Ser. No. 10/906,171, filed Feb. 5, 2005, the contents of each of which are expressly incorporated herein by reference.  
         [0032]     In one exemplary embodiment, the clip housing  26  defines an interior cavity  72  sized to receive the tip protector  70 . In a preferred embodiment, the clip housing  26  remains with the tip protector  70  following activation, such as that shown in  FIG. 2 , by incorporating a housing top  30  having an opening  28  formed therethrough. Alternatively, the housing top  30  may be eliminated so that following an injection, the tip protector  70  may pass through the opening where the housing top  30  would otherwise be incorporated. If the housing top  30  is eliminated, an inward projection should be incorporated in the interior cavity  72  of the clip housing  26  for retaining the tip protector  70  with the housing during movement from between a ready to use position to an activated position. The inward projection defines a section in the interior cavity  72  with a smaller diameter than the diameter of the cavity at the opening  74  of the housing, which is the same as near the housing top  30 . Following activation, the clip collapses over the needle tip and has a smaller profile that enables it to pass through the projection inside the interior cavity to thereby separate from the clip housing  26 .  
         [0033]     In one exemplary embodiment, a flange  76  is incorporated on the clip housing  26 , preferably at the opening  74  of the clip housing. The flange  76  is configured to project into the gap  65  at the base  66  of the needle hub  22  when the port access device  10  is in the ready to use position, as further discussed below.  
         [0034]     As previously alluded to, the catheter hub incorporates a septum  78  for occluding the needle port  80  above the septum. The septum  78  is incorporated by providing a recessed space  82  in the lower hub block  42  for receiving the septum. Part of the needle port  80  extends below the septum  78  and is in fluid communication with the catheter tube  14 . A flow chamber  84  is incorporated in the lower hub block  42  and is in fluid communication with the catheter  14 . The flow chamber  84  is preferably sized to receive a tubing (not shown) and has a tapered wall for a tapered fit with the tubing. As is readily apparent to a person of ordinary skill in the art, the flow chamber  84  acts as a conduit for passing fluid flow from between the catheter tube  14  and the tubing, such as, e.g., for taking a sample from an injection site, for administration of medications, for administration of fluids, and for transfusion of blood products.  
         [0035]     Also shown in  FIG. 2  is a cross-sectional side view of the bridge  50  of the low profile wing  46 , which passes through the seam  44  adjacent the septum  78 . A side edge  86  of one of the wing flaps  48  is also shown. It is clear that in the embodiment shown, the wing flaps  48  comprise a length that that extends past the end  45  of the catheter hub  16 .  
         [0036]      FIG. 3  is a cross-sectional side view of the port access device  10  in a ready to use position. The device  10  is placed in the ready to use position by first engaging the housing top  30  of the clip housing  26  with the threaded recess boss  62  of the needle hub cavity  60 . This is accomplished by rotating either the clip housing  26  or the needle hub  22  relative to the other. The tip protector  70  is then moved to a proximal most position inside the clip housing  26 . The needle  20  is then advanced through the needle bore  80  and through the septum  78 . The needle hub  22 , with the clip housing  26  attached thereto, is advanced until the base  68  of the projection  64  contacts the upper surface of the catheter hub  16  and the teeth  38  on the clip housing  26  engage the detents  58  on the catheter hub  16 .  
         [0037]     In one exemplary embodiment, the teeth  38  each incorporates a lip  88  configured to positively engage the detents  56 . A snug fit between the needle  20  and the septum  78  and between the lips  88  and the detents  56  firmly secures the combination needle hub  22  and clip housing  26  to the catheter hub  16 . In the embodiment shown, the teeth  38  are each attached to the body section  34  of the clip housing  26  via two side walls  90  (with only one shown in the  FIG. 3  cross-sectional view), which define a gap or a channel therebetween. In an alternative embodiment, the clip housing  26  incorporates a pin under the flange  76  and the catheter hub  16  a corresponding boss to prevent relative rotation. In yet another alternative embodiment, the clip housing  26  and the bore  60  may incorporate detents to control axial movement instead of threads, as further discussed below.  
         [0038]      FIG. 4  is an enlarged view of the needle tip  92  extending past the distal end  100  of the catheter tube  14 . In one exemplary embodiment, the catheter tube  14  comprises an internal diameter  96  sized about 4 mils to about 30 mils larger than the outside diameter of the needle  20 , with a range of 4 mils to 12 mils being more preferred. An annular space  98  is formed due to the size difference between the internal diameter  96  of the catheter tube and the outside diameter of the needle  20 . The distal end  100  of the catheter tube  14 , however, is reduced so that the distal end of the catheter tube  14  has an opening  24  that is smaller in diameter than the internal diameter  96  of the tube. In a preferred embodiment, the end opening  24  is about the same size as the diameter of the needle  20 . In a more preferred embodiment, the end opening is about 0.5 mil to about 1.5 mil smaller than the diameter of the needle  20 . A seal or a close tolerance fit is thus formed by the relative dimensions between the end opening  24  of the catheter tube and the needle  14 .  
         [0039]      FIG. 5  is a cross-sectional side view of the access port device of  FIG. 3  with the needle hub  22  rotated relative to the catheter hub  16  and the clip housing  26 . In other words, the catheter hub  16  and the clip housing  26  are fixed or are substantially fixed to one another while the needle hub  22  is rotated relative to the two. In one exemplary embodiment, the needle hub  22  is rotated a quarter turn counter-clockwise to disengage the housing top  30  of the clip housing  26  from the threaded boss  62  located in the cavity  60  of the needle hub. In a preferred embodiment, the quarter turn counter-clockwise causes the hub  22  to move about 0.050 inch axially, which corresponds to a 0.050 inch lead at a quarter turn on the threads. Because the needle  20  is attached to the needle hub  22 , the axial movement causes the tip  92  to move the same distance, which moves it into the lumen of the catheter tube  14 .  
         [0040]     With reference to  FIG. 6  in addition to  FIG. 5 , the annular space  98  is exposed to the end opening  24  of the catheter tube  14 . Had the port access device  10  being used on a port site and rotated as described, blood flashback would flow through the annular space  98  and the flow chamber  84  and out through the tubing (assuming one is attached to the flow chamber). Blood flashback provides an indicator that the port access device  10  is properly placed through an injection port housing of an implantable catheter. If placement of the port device  10  is satisfactory, the needle  20  may be retracted completely while leaving the catheter hub  16  and catheter tube  14  in place.  
         [0041]     To retract the needle  20  from the catheter tube  14 , the needle hub  22  is moved axially away from the catheter hub  16 . Once the tip  92  moves proximally of the septum  78  and into the upper needle port chamber  80 , the clip housing  26  may start to move, shift, or tilt as the combination needle and septum no longer provides an anchoring point to securely hold the clip housing  26  in place. The hub  22  is further retracted proximally until the needle tip moves just proximal of the two distal walls  102  of the tip protector  70 , at which time or approximately contemporaneously thereto, the proximal opening  104  on the tip protector  70  engages a bump, crimp, deformity, or change in profile (not shown) on the needle  20 . Still further proximal movement of the needle hub will lift the combination clip housing  26  and tip protector  70  away from the catheter hub  16  due to the engagement between the opening  104  on the proximal wall of the tip protector and the bump or crimp on the needle. Referring again to  FIG. 2 , the activated clip  70  and clip housing  26  will appear as shown when activated.  
         [0042]     Although limited embodiments of the port access device and their components have been specifically described and illustrated herein, many modifications and variations will be apparent to those skilled in the art. For example, the shape of the catheter hub, needle hub, and/or clip housing may be modified, the plastic can be mo, etc. Furthermore, it is understood and contemplated that features specifically discussed for one valve embodiment may be adopted for inclusion with another valve embodiment, provided the functions are compatible. For example, certain curvatures and contours incorporated in one valve may be incorporated in another valve for aesthetic appeal and improved functionality, such as for improved gripping purposes. Accordingly, it is to be understood that the valve assemblies and their components constructed according to principles of this invention may be embodied other than as specifically described herein. The invention is also defined in the following claims.