Abstract:
There is provided a needle device for percutaneous drug delivery to a patient. The device comprises a substantially L-shaped, hollow needle for drug delivery therethrough and a body. The needle includes a needle end and the body is secured to the needle and longitudinally spaced from the needle end. The body includes an integral pair of flexible handles adapted to be grasped for insertion of the needle device into and removal of the device from the patient.

Description:
FIELD OF THE INVENTION 
   This invention relates to a drug delivery needle and more specifically to a needle for percutaneous injection of a drug into an implanted drug delivery device having a catheter for drug delivery to a patient. 
   BACKGROUND OF THE INVENTION 
   Drug delivery devices are commonly implanted in a patient for long-term administration of drugs. These devices generally include a chamber with a self-sealing silicone septum and a catheter attached to the chamber and positioned for delivery of the drug to a suitable location, for example, into a vein. The chamber contains the drug for delivery to the patient through the catheter and is implanted such that the septum is located just under the skin of the patient. In order to access the chamber, the patient&#39;s skin and the septum of the drug delivery device are pierced using a needle and the drug is introduced into the chamber by injection using a syringe or other delivery device. 
   Conventional hypodermic needles are not used for the introduction of a drug to a drug delivery device for various reasons including, for example, the possibility that these needles can damage the septum. Instead, specially designed needles are used to pierce the skin and the septum. These needles include a right angle bend (approximately a ninety degree bend) for convenient access to the chamber and are designed to inhibit coring of the septum and ensure penetration of the skin and septum at approximately ninety degrees. The needles are appropriately sized to access the chamber of the device. A portion of the needle lies approximately parallel with the surface of the skin of the patient, to allow the needle to be taped down. 
   While they are an improvement over conventional needles, right-angle needles can still be somewhat difficult to hold and to push through the skin and the septum since the physician must firmly grasp the needle in order to drive the needle through the septum. Also, when taped down on the patient, prior art needles do not allow flow of air around the wound site. This can contribute to infection of the wound. 
   One particular prior art drug delivery needle is disclosed in U.S. Pat. No. 4,743,231, issued May 10, 1988 to Kay et al. This patent teaches a right angle drug administration needle with a rigid base for taping down to the skin of a patient and a releasably connectable handle for ease of handling. A foam pad extends around the periphery of the underside of the base and includes an adhesive surface for adhering to the skin of the patient. A low profile allows for the right angled needle device to be taped down to the user while the foam pad provides flow of air around the wound site. 
   Although this structure provides a handle for firmly grasping the needle and a foam pad for flow of air around the wound site, the drug delivery needle device still suffers from some disadvantages. The handle is molded separately from the remainder of the needle device and is releasable to provide a low profile when the device is taped down. Thus, when the tape is removed from the patient, the physician is required to find the handle and attach the handle to the base in order to remove the needle. Since the handle is removable, it can easily be misplaced or lost. Also, the base is rigid and does not conform to the skin surface of the patient. 
   Accordingly, it is an object of an aspect of the present invention to provide a drug delivery needle for percutaneous delivery of a drug into an implanted drug delivery device that obviates or mitigates at least one of the disadvantages of the prior art. 
   SUMMARY OF THE INVENTION 
   In one aspect of the present invention there is provided a needle device for percutaneous drug delivery to a patient. The device comprises a substantially L-shaped, hollow needle for drug delivery therethrough and a body. The needle includes a needle end and the body is secured to the needle and longitudinally spaced from the needle end. The body includes an integral pair of flexible handles adapted to be grasped for insertion of the needle device into and removal of the device from the patient. 
   Advantageously, the handles of the drug delivery device are attached to the remainder of the device. Also, the drug delivery device includes a spacer that spaces the handles away from the wound site when the drug delivery device is taped down on the patient. In an aspect of the invention, a portion of the L-shaped needle extends approximately from the center of a body between the pair of flexible handles. Thus, downward force on the body of the device is transmitted to the needle when the needle is inserted into the patient. This provides support and accuracy during insertion of the needle. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will be better understood with reference to the drawings, and following description, in which: 
       FIG. 1  is a perspective view of a needle device according to a preferred embodiment of the present invention; 
       FIG. 2  is an alternative perspective view of the needle device of  FIG. 1 ; 
       FIG. 3  is a cross-sectional front view of the needle device of  FIG. 1  showing the device in use with a needle inserted into a chamber (shown in ghost outline) under the skin of a patient and showing a pair of handles, flexed in opposing directions in ghost outline; 
       FIG. 4  is a bottom view of the needle device of  FIG. 1 , showing the needle in cross-section; 
       FIG. 5  is a perspective view of the needle device of  FIG. 1 , showing the handles being grasped; and 
       FIG. 6  is a front view of the needle device of  FIG. 5 , showing the handles being grasped. 
   

   DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
   Reference is first made to  FIGS. 1 and 2  to describe a preferred embodiment of a drug delivery needle device designated generally by the numeral  20 . The drug delivery needle device includes a substantially L-shaped needle  22  for drug delivery therethrough. The needle  22  consists of first portion  24  and a second portion  26  with an included angle between the first portion  24  and second portion  26 , forming the L-shape. In the present embodiment, the included angle is approximately ninety degrees. The needle  22  is hollow to define a continuous fluid passage through the first and second portions  24 ,  26 , respectively. The first portion  24  of the needle  22  is attached to a flexible tube and will be described further below. The second portion  26  of the needle  22  includes a needle end  30  that is slightly bent with respect to the remainder of the second portion  26  and is longitudinally spaced from the first portion  24 . The end  30  is bent to provide a non-coring needle, as will be understood by those of skill in the art. As shown in the figures, the continuous fluid passage is open at the needle end  30  and the needle end  30  is sharp for piercing the skin of a patient and for piercing a septum of a chamber of a catheter, for example. 
   A body  32  is molded of a resiliently flexible plastic around the first and second portions  24 ,  26 , respectively. The body  32  includes a substantially rectangular base  34 , a spacer  36 , a pair of flexible handles  38 ,  39  and a cover  40 , as discussed further below. 
   The substantially rectangular base  34  is molded around the second portion  26  and is longitudinally spaced from the end  30  such that the second portion  26  of the needle  22  passes through and extends from the base  34 . A foam pad  42  extends around the periphery of one side of the base  34 . The foam pad  42  is an open-celled plastic foam to allow air flow therethrough, thereby providing a layer that allows the flow of air between the molded plastic base  34  and the skin of a patient when in use. In the present embodiment, the foam pad and base are flexible for patient comfort. 
   One end  44  of the spacer  36  is coupled to a second side of the base  34  and the opposing end  46  is coupled to the cover  40 . It can be seen that the first portion  24  of the needle  22  extends through the cover  40  such that the cover  40  and the first portion  24  form a rigid spine  48  that provides rigidity for the device  20 . The second portion  26  of the needle  22  extends through the spacer  36  and the base  34 . As shown in  FIGS. 1 ,  2  and  3 , the second portion  26  of the needle  22  extends longitudinally and is approximately perpendicular to the base  34 , while the spine  48  is approximately parallel with the base  34 . 
   Referring to  FIG. 3 , each of the flexible handles  38 ,  39  extends laterally from and is coupled to the spine  48  such that the spine  48  is located between the handles  38 ,  39 . The spine  48  effectively couples the handles  38 ,  39  to the spacer  36  which spaces the handles  38 ,  39  from the base  34 . Each of the handles  38 ,  39  includes a groove  50 ,  52 , respectively, extending along the width of the handles  38 ,  39 , adjacent the spine  48 . The handles  38 ,  39  also include distal ends  54 ,  56 , respectively, that are laterally spaced from the spine  48  and the grooves  50 ,  52 . These grooves  50 ,  52  provide a thin region in comparison with the remainder of the handles  38 ,  39 . This provides increased flexibility in this region. In order to grasp the device  20 , the handles  38 ,  39  are flexed away from the base  34  such that backsides  58 ,  60  of each of the respective handles  38 ,  39  are in contact with each other at the distal ends  54 ,  56 . Thus, the handles  38 , 39  are effectively pinched together when grasped, as best shown in  FIGS. 5 and 6 . When no longer grasped, the handles  38 ,  39  return to their laterally extending state. As shown in the Figures, the second portion  26  of the needle  22  extends approximately from the center of the body  32 , between the pair of flexible handles,  38 ,  39 . 
   The handles  38 ,  39  can also flex in the opposite direction. It will be appreciated that the handles  38 ,  39  are spaced from the base  34  in order to inhibit contact of the handles  38 ,  39  with a patient&#39;s skin proximal the wound site when the device  20  is in use. 
   Referring again to  FIG. 1 , a flexible tube  62  is connected to and in fluid communication with the first portion  24  of the needle  22 . The tube  62  extends outwardly from the spine  48 . The flexible tube  62  is made of a suitable plastic for delivery of a drug through the tube  62 , into the first portion  24  of the needle. 
   Although each of these elements are described separately, it will be appreciated that in the present embodiment the base  34 , the spacer  36 , the handles  38 ,  39  and the cover  40  are a unitary molded plastic. 
   The use of the drug delivery device  20  will now be described with reference to  FIGS. 3  to  6 . For the purpose of the present description, a chamber with a self-sealing septum, shown in ghost outline in  FIG. 3 , is implanted such that the chamber is located just under the skin of the patient. The chamber is designed to contain the drug for delivery to the patient through a catheter. The use of a chamber and self-sealing septum is understood in the art and will not be further described herein. 
   In order to access the chamber, the patient&#39;s skin and the septum are pierced using the device  20 . To accomplish this, the handles  38 ,  39  of the device  20  are flexed by pinching the handles  38 ,  39 , preferably between the thumb and the forefinger, such that they are in contact with each other at the distal ends  54 ,  56  of the backsides  58 ,  60 , as shown in  FIGS. 5 and 6 . Next, the needle end  30  is positioned at the desired location on the skin of the patient (at the location of the self-sealing septum). Pressure is then applied towards the surface of the skin causing the end  30  of the needle  22  to puncture the skin and the self-sealing septum of the chamber. It will be appreciated that the spine  48  provides rigidity to the device  20  when the needle  22  is being inserted or extracted from a patient. As stated above, the second portion  26  of the needle  22  extends approximately from the center of the body  32 , between the pair of flexible handles,  38 ,  39 . The needle is inserted until the foam pad  42  is adjacent the patient&#39;s skin. With the needle end  30  located in the chamber, the fluid or drug is then delivered to the chamber through the flexible tube  62 , through the first and second portions  24 ,  26 , respectively and out the needle end  30 . 
   It may be desirable to leave the device  22  with the end  30  of the needle  22  inserted into the chamber for a long period of time. In such case, the device is generally taped to the skin of the patient. Thus, the handles  38 ,  39  are flexed in the direction of the skin of the patient. Since the spacer  36  spaces the handles  38 ,  39  from the base  34 , the handles are effectively inhibited from contacting the skin of the patient immediately around the foam pad  42  on the base  34 . The foam pad  42  allows for the flow of air around the wound site (where the needle puncture is located). 
   To remove the device  20 , any tape that has been used to secure the device  20  is first removed. The handles  38 ,  39  are then grasped, as discussed above, and pulled outwardly, away from the patient. Thus, the needle  22  is removed from the patient and the septum of the chamber seals. 
   While the embodiment discussed herein is directed to a particular implementation of the present invention, it will be apparent that variations and modifications to this embodiment are possible. For example, the L-shaped needle can have any suitable included angle and can vary from ninety degrees. Also, the body structure described above does not need to be a unitary molded structure and can be individual pieces coupled together. The size and shape of many of the parts can vary while still performing the same function. All of these variations and modifications are within the scope sphere of the invention as defined by the claims appended hereto.