Abstract:
A protective sheath for a winged needle has a hilt with a keyhole for releasably receiving a length of tubing. Methods of the invention include forming a U-shaped bend in the tubing and inserting it into the keyhole prior to packaging.

Description:
This application is related to co-owned U.S. Pat. No. 5,330,438, and published application number 20020188260, the complete disclosures of which are hereby incorporated herein by reference. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a protective sheath or safety guard for winged needles and, in particular, to a protective sheath having a keyhole for releasably retaining the flexible tubing of a winged needle set and a method of packaging a winged needle set having such a protective sheath. 
   2. State of the Art 
   A well known winged needle (also known as a butterfly needle) assembly is shown in prior art  FIG. 1 . The assembly  10  includes a needle  12  having a pair of wings  14 , coupled to a first end of a length of coiled flexible tubing  16 , and a coupling attached to the rear end of the tubing by which this winged needle set or assembly may be attached to, e.g., means for piercing a vacuum bottle for blood collecting or a Luer lock tapered coupling for IV tubing. The winged needle assembly has been used for many years in, e.g., the administration of IV medications and in obtaining blood samples when use in conjunction with vacuum bottles. The purpose of the assembly is to limit trauma to the patient&#39;s blood vessel(s), particularly-when multiple samples of blood are to be taken or when multiple types of medication are to be administered. After the needle is inserted into the patient&#39;s blood vessel, the wings are taped to the patient&#39;s body to prevent movement of the needle when coupling/uncoupling the Luer lock or attaching or disconnecting the vacuum bottle used for blood collecting. Any movement of the needle can cause trauma of the patient&#39;s blood vessel. The winged needle assemblies are typically packaged with the flexible tubing wound in a coil such as illustrated in  FIG. 1 , typically coiled in several loops. It has recently been discovered by the inventor herein that when a winged needle kit is packaged with the tubing coiled, the tubing tends to retain a coiled configuration even after it is unpackaged. It has also been discovered by the inventor herein that when the flexible tubing has retained a coiled configuration, even a slight movement of one end of the tubing will disadvantageously cause immediate movement of the other end. 
   In the 1980s after the discovery of the HIV virus which causes AIDS, much attention was given to the problem of accidental needlesticks from contaminated medical equipment such as syringes and IV equipment, which poses serious risks to healthcare professionals. Even maintenance personnel who dispose of the used medical equipment are at risk. Hepatitis, AIDS and other diseases can be, and sometimes are, transmitted by accidental needlesticks from needles used on infected patients. 
   My prior U.S. Pat. No. 5,330,438 discloses an improved sheath construction (shown in prior art  FIG. 2 ) which significantly minimizes the possibility of improper operation and jamming of the used needle relative to the sheath during the sheathing operation. The IV infusion set  20  includes an IV tube  22 , a hollow needle  24  coupled to one end of the tube and two wings  26  adjacent the needle  24 . A Luer connector (not shown) is connected to the other end of the IV tube. The IV infusion set  20  also includes a sheath  28  slidably disposed on tube  22 . The sheath  28  is adapted to be slid past the flexible wings  26  to cover the needle after the needle has been used. 
   The sheath  28  preferably includes a knurled, generally cylindrical, annular base  29  by which the sheath may be easily grasped. Base  29  has a central bore (not shown) through which tube  22  may slidably pass and is integrally joined to a hollow generally tubular body  30  having a forward end  32  oriented toward the needle  24  and a rearward end  34  oriented away from the needle. The body  30  preferably has four fingers  35  separated by four longitudinally extending slots  36  extending from the forward end or tip  32  of body  30  to the rearward end  34 . The slots  36  are each adapted to receive only one of the wings  26  to allow at least part of the sheath  28  to be slid past the wings  26  to cover the needle  24 . 
   The body  30  also includes cutouts  42  at the rearward end of the slots  36 , adapted to receive and engage the wings  26  to lock the sheath in its position covering the needle. The cutouts  42  have a width approximately equal to the width of one of the wings  26 . Slot  36  is slightly narrower than the thickness of the wings. As a result, as the wings  26  pass through the slots  36 , the fingers  35  will resiliently wedge apart, and upon passage of the wings  26  into the wider cutouts  42 , snap back and assume their normal position, thereby trapping the wings  26  in the cutouts  42  behind the forward edges  44  of the cutouts. This prevents the needle  24  from sliding forwardly out of the sheath  28 . 
   Recently, the U.S. Food and Drug Administration has requested that all safety devices used with needles either change color or produce an audible sound or provide some other easy to recognize evidence that the needle has been rendered safe. My prior application 20020188260 addresses that concern and provides other improvements. 
     FIGS. 3 and 4  illustrate the needle sheath of said published application. The sheath  128  is provided in conjunction with a hollow needle  124  with a pair of wings  126 . The sheath  128  includes at least a pair of fingers  132 ,  140  extending from an annular base  130 . ( FIG. 4  illustrates an embodiment  128 ′ with four fingers  132 ′,  133 ,  140 ′,  141 ). The fingers define a pair of slots  142  through which the wings  126  of the needle  124  may slide. The slots define an open end  146  and a closed end  154 . The slots  142  are provided with a Z-bend  153 ,  155 . The Z-bend is dimensioned such that the wings  126  can pass through it with some deformation, and an audible click is heard as the wings and/or fingers cease to be deformed. As seen in  FIG. 3 , the fingers  132 ,  140  terminate in a first annular structure  138  which is separated from the annular base  130  by a hilt  134 . As shown in  FIG. 3 , the hilt  134  has two angled ends  150 ,  152 , although the angled ends may be omitted as shown in  FIG. 4  at  134 ′. The hilt  134  assists in holding the sheath while sliding the sheath and of the wings into the locked position shown in  FIG. 3 . 
   SUMMARY OF THE INVENTION 
   Accordingly, it is an object of the present invention to overcome the disadvantages imposed by packaging a winged needle and tube assembly with the tubing coiled. 
   It is a further object of the present invention to include the advantages of my prior inventions. 
   The foregoing and related objects are readily achieved in a winged needle and tube assembly of the type including a length of flexible tube with a hollow needle at one end, and a pair of outwardly projecting flexible wings adjacent the end of the tubing with the needle and a sheath slidably disposed on the tube and adapted to be slid over the needle to cover the needle after use. The sheath comprises a hollow generally tubular body having a forward end oriented toward the needle and a rearward end oriented away from the needle. The body has at least two longitudinally extending fingers separated by slots extending from the forward end of the body toward the rearward end, each of the slots being dimensioned to receive only one of the wings to allow at least part of said sheath to be slid past the wings to cover the needle. The sheath is provided with a hilt which facilitates the sliding of the sheath and/or wings into a locked position where the sheath covers the needle. According to the invention, the hilt is provided with at least one keyhole for removably securing the flexible tubing. 
   Certain of the foregoing and related objects are attained according to the invention by the provision of a winged needle set, comprising a winged needle, a length of flexible tubing having first and second ends, said first end coupled to said needle, and a protective sheath slidably disposed on said tubing, said sheath having a hilt with said hilt having a keyhole dimensioned to releasably retain said tubing. Preferably, the winged needle set additionally includes a connector coupled to said second end of said flexible tubing and said hilt has two keyholes, each on opposite sides of said hilt. 
   Advantageously, the sheath comprises a hollow generally tubular body having a forward end oriented toward the needle and a rearward end oriented away from the needle with said body having at least two fingers defining slots through which said flexible wings slide. Most desirably, at least one of said wings slides into a locked position. The tubular body preferably has four fingers and four slots, each of said slots being provided with a Z-bend and the forward end of said fingers are V-shaped and tapered to facilitate the passage of said wings into the slots. Most advantageously, the sheath includes means for locking the sheath in a position covering the needle to prevent needlesticks from the needle. 
   Certain of the foregoing and related objects are also attained in a method of packaging a flexible tubing coupled to a winged needle having a protective sheath slidably mounted on said tubing having a hilt with a keyhole, comprising the steps of: forming a U-shaped bend in the length of flexible tubing, and inserting a section of the flexible tubing into the keyhole of the protective sheath so as to maintain the U-shaped bend. Most advantageously, the U-shaped bend is formed at the approximate midpoint of the tubing. Preferably, the method involves the further steps of positioning said sheath adjacent to said U-shaped bend, placing the tubing, needle, and sheath into a package, and sealing the package. 
   Certain of the foregoing and related objects are also attained in a protective sheath for a winged needle according to the invention which sheath comprises a hollow generally tubular body having a forward end oriented toward the needle and a rearward end oriented away from the needle, said body having at least two fingers defining slots, and a hilt at the rearward end of said body, said hilt defining at least one keyhole adapted to releasably receive a length of flexible tubing. Preferable, the sheath has means for locking said winged needle within said tubular body of said sheath and said tubular body has four fingers and four slots, each of said slots being provided with a Z-shaped bend. 
   In a-preferred embodiment of the invention, the forward end of said fingers are V-shaped and tapered to facilitate the passage of said wings into the slots and said sheath includes means for locking the sheath in a position covering the needle to prevent needlesticks from the needle. The tubing is preferably made of medical grade plastic tubing. 
   The invention is based on two discoveries, the first being the recognition of a problem not previously recognized, i.e., that the coiled shape retained by flexible medical tubing (e.g., IV tubing) which is coiled in its package causes the ends of the tubing to be mechanically responsive to each other. Movement of one end of a coiled IV tube causes immediate movement of the other end. The second discovery is that when the flexible tubing is packaged with only a single U-shaped bend, it retains its flexibility so that relatively large movement of one end has very little effect on the other end, i.e., movement of one end doesn&#39;t cause appreciable movement of the other end. This, in turn, reduces possible trauma to the injection site (patient&#39;s blood vessel) caused by movement of the needle. 
   Additional objects and advantages of the invention will become apparent to those skilled in the art upon reference to the detailed description taken in conjunction with the provided figures. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a plan view of a conventional IV infusion set having a winged needle; 
       FIG. 2  is a perspective view of a winged needle and protective sheath according to my prior patent; 
       FIG. 3  is a side elevation view of a sheath according to my previously incorporated published application with the wings of a winged needle beyond the Z-bend in the slot of the sheath and thus in a locked position; 
       FIG. 4  is an end view of a sheath according to my previously incorporated published application with a slightly different shaped hilt; 
       FIG. 5  is a view similar to  FIG. 4  but illustrating the hilt according to the present invention; and 
       FIG. 6  is a plan view of a winged needle set according to the invention illustrating a method of using the hilt keyhole and a method of packaging the set. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Referring now to  FIGS. 5 and 6 , a winged needle set  200  according to the invention is shown which can be used in the medical field as, e.g., an IV infusion or blood collecting set. The winged needle set  200  includes a needle  202  having a pair of wings  204 , and a length of medical grade, plastic flexible tubing  206 . The tubing  206  has a first end  208  which is coupled to the needle  202  and a second end  210  which is typically coupled to a connector  212 , e.g., a Luer lock tapered coupling for IV tubing or a threaded connector coupled to a needle for piercing a blood-collecting bottle. A protective sheath  214  having a hilt  216  is slidably disposed on the tubing  206 . According to the present invention, the hilt  216  is provided with a first keyhole  218 , and preferably also a second keyhole  220  as illustrated in  FIG. 5 . The characteristics of the winged needle set  200 , other than the keyholes, are substantially the same as described in my previously incorporated published application. 
   According to methods of the invention, the flexible tubing  206  is bent approximately in half to define a U-shaped bend  222  and the sheath  214  is moved or shifted along tubing  206  to a position adjacent to the U-shaped bend  222 . A portion or section of the tubing  206  adjacent the U-shaped bend  222  is inserted into one of the keyholes, e.g.,  218  as shown in  FIG. 6 . This maintains the tubing with this U-shaped bend  222  at a location approximately midway between the first end  208  and the second end  210  of the tubing  206 . Due to the size of the hilt, this bend  222  has a relatively small diameter. With the winged needle set  200  so configured, it is placed in a substantially rectangular package  224 . The package may be made of any suitable sterile barrier material. 
   By pushing the flexible tubing into the keyhole before packaging, it forces the originally straight tubing to remain in a U-shape consisting of two straight lengths and one small diameter bend  222  at the approximate midpoint of the tubing  206 . When the flexible tubing  206  is forced to remain in the same shape for a prolonged period of time, especially during the conditions of most sterility processes, it tends to retain most of the shape. Therefore, when the winged needle set  200  is removed from its package  224 , and the flexible tubing  206  is pulled free from the keyhole  218 , the flexible tubing  206  will remain with the shape of two straight lengths and one small diameter bend  222  at the approximate midpoint of the tubing  206 . 
   The keyhole provides a fast, easy, and inexpensive method to produce the above-described U-shape in the tubing. It also changes the entire assembly into a long thin shape rather than a short fat coil shape. This long thin shape is easy to handle with standard packaging machinery. Most brands of winged needle sets are coiled and slid into a separate plastic sleeve to hold it in a workable shape so that it can be easily handled and transferred into standard packaging machines. The present invention reduces the cost of packaging because: there is no need to coil the tubing; there is no need to purchase and cut-to-length plastic sleeving; and there is no need to place the coiled tubing into a plastic sleeve prior to packaging. 
   According to the present invention, the tubing is quickly snapped into the keyhole on either side of the hilt, giving the tubing a workable “U” shape which can then easily be placed into a packaging machine or directly into the package. 
   There has been described and illustrated herein a protective sheath for butterfly or winged needles, a winged needle set, and methods for packaging the set. While particular embodiments of the invention have been described, it is not intended that the invention be limited thereto, as it is intended that the invention be as broad in scope as the art will allow and that the specification be read likewise. It will therefore be appreciated by those skilled in the art that yet other modifications could be made to the provided invention without deviating from its spirit and scope as so claimed.