Abstract:
Safety needle assemblies that include a needle having a sharp distal tip and a needle tip cover mounted on the needle are disclosed. The needle tip cover includes a first portion having a channel receiving the needle and a second portion attached to the first portion. The second portion has a proximal wall, an opening in the proximal wall receiving the needle, a sidewall extending distally from the proximal wall, first and second spring arms extending transversely from opposite edges of the sidewall, and a third spring arm extending distally from the sidewall. The first spring arm and the second spring arm extend at least partially around the first portion. The third spring arm includes a flange extending radially inward and configured to bear against the needle to deflect the third spring arm radially outward against a spring restoring force in a ready to use position.

Description:
FIELD OF ART 
       [0001]    The present invention is generally directed to needle safety assemblies and related methods and more particularly to needle safety assemblies and related methods utilizing needle guards. 
       BACKGROUND 
       [0002]    Insertion procedure for an intravenous (IV) catheter assembly includes the following four basic steps: (1) the healthcare worker inserts the needle and catheter together into the patient&#39;s vein; (2) after insertion into the vein with the needle point, the catheter is advanced into the vein of the patient by the healthcare worker pushing the catheter hub with his or her finger; (3) the healthcare worker withdraws the needle by grasping the needle hub end (opposite the point end) while at the same time applying pressure to the patient&#39;s skin at the insertion site with his or her free hand to stop the flow of blood through the catheter; and (4) the healthcare worker then tapes the exposed end of the catheter (the catheter hub) to the patient&#39;s skin and connects it to the source of the fluid to be administered into the patient&#39;s vein. 
         [0003]    One potential problem with traditional procedure is that immediately after the withdrawal of the needle from the patient&#39;s vein, the healthcare worker, who is at this time involved in at least two urgent procedures, must place the exposed needle tip at a nearby location and address the tasks required to accomplish the needle withdrawal. It is at this juncture that the exposed needle tip creates a danger of an accidental needle stick, which, under the circumstances, can leave the healthcare worker vulnerable to the transmission of various dangerous blood-borne pathogens, including AIDS and hepatitis. 
         [0004]    Other needle types similarly expose healthcare workers to risks of accidental needle sticks. For example, a doctor administering an injection using a straight needle, a Huber needle, an epidural needle, etc., may place the used needle on a tray for subsequent disposal by a nurse. For the period between placing the used needle on a tray or a work station to the time it is discarded, the used needle is a potential source for disease transmissions for those that work near or around the needle. 
       SUMMARY 
       [0005]    The various embodiments of a needle assembly have several features, no single one of which is solely responsible for their desirable attributes. Without limiting the scope of the present embodiments as set forth in the claims that follow, their more prominent features now will be discussed briefly. 
         [0006]    A catheter assembly provided in accordance with aspects of the present disclosure can comprise a catheter tube extending distally from a distal end of a catheter hub, a needle hub having an interior cavity, a needle guard having a lengthwise axis and comprising a sleeve having a proximal end attached to the needle hub and a tip cover attached at a distal end of the sleeve, the sleeve surrounding at least a portion of the needle and the tip cover comprising a nose section and a perimeter defining a side opening located off-axis from the lengthwise axis of the needle guard, a needle with a needle tip projecting through the sleeve, the side opening of the tip cover, the catheter hub, and the catheter tube in a ready to use position with the needle tip extending distally of a distal opening of the catheter tube. 
         [0007]    A valve can be positioned in an interior cavity of the catheter hub. 
         [0008]    The catheter hub can be a ported catheter with an injection port. 
         [0009]    A port cap assembly can cap the injection port of the ported catheter. 
         [0010]    The valve can have a port valve sealing the injection port from an interior cavity of the catheter hub, and an inlet valve sealing fluid flow from a proximal opening of the catheter hub. 
         [0011]    The sleeve can be elastic and compressed in the ready to use position. 
         [0012]    The sleeve can be compressed and bent near a distal end of the sleeve. 
         [0013]    The sleeve can be made of a compressible syntactic rubber, neoprene, or isoprene. 
         [0014]    The sleeve can be attached to the needle hub via a ring fixed to the proximal end of the sleeve and inside a distal shroud of the needle hub. 
         [0015]    The tip cover can slide relative to the needle from the ready to use position to a secured position where the needle tip enters into the tip cover through the side opening. 
         [0016]    The side opening can have a width larger than a diameter of the needle. 
         [0017]    A perimeter of the side opening can be smooth to minimize friction between the needle and the tip cover. 
         [0018]    The tip cover can abut against the catheter hub in the ready to use position. 
         [0019]    The tip cover can abut against the catheter hub and the sleeve can be attached to the needle hub in the ready position and during retraction of the needle away from the catheter hub. 
         [0020]    The tip cover can further comprise a flap extending in a proximal direction inside the tip cover from a distal end of the side opening, said flap being configured for preventing the needle tip from emerging out of the side opening from the secured position. 
         [0021]    The tip cover can be made of metal. Alternatively, the tip cover can be made from POM (polyoxymethylene) or ABS (acrylonitrile butadiene styrene). 
         [0022]    The tip cover can be tethered to the needle hub. 
         [0023]    The tether can be a folded mechanism attached to the tip cover and the needle hub. 
         [0024]    The folded mechanism can be attached to a nose plate, which is attached to the tip cover. 
         [0025]    The folded mechanism can comprise a plurality of legs folded in the interior cavity of the needle hub in the ready to use position. 
         [0026]    The tip cover and the folded mechanism can be integrally formed. 
         [0027]    An air vent housing can be attached to a proximal end of the needle hub, a closing cap attached to a proximal end of the air vent housing, and a filter sandwiched between the air vent housing and the closing cap. 
         [0028]    A further aspect of the present disclosure can include a method of making a catheter assembly which can comprise providing a catheter unit comprising a catheter hub with a hub body, a catheter tube extending distally from a distal end of the catheter hub, and a valve positioned in an interior cavity of the catheter hub, providing a needle hub unit comprising a needle hub having an interior cavity, a needle with a needle tip extending distally from the needle hub, and a needle guard having a lengthwise axis coupled to the needle hub, said needle guard comprising an elastic sleeve having a proximal end coupled to the needle hub, and a tip cover attached to a distal end of the sleeve, said tip cover having a nose section and a side opening located off-axis from the lengthwise axis of the needle guard, extending the needle through the elastic sleeve and out the side opening on the tip cover, through the valve, and through the catheter tube with the needle tip extending distally of a distal opening of the catheter tube in a ready to use position, compressing the elastic sleeve against the catheter hub and the needle hub in the ready to use position, and tilting the nose section of the tip cover from the lengthwise axis of the needle guard. 
         [0029]    A side injection port can extend from the hub body. 
         [0030]    A port cap assembly can cap an injection port. 
         [0031]    The method can further comprise sliding the tip cover relative to the needle from the ready to use position to the secured position. 
         [0032]    The sleeve can be attached to the needle hub via a ring at the proximal end of the sleeve and the distal nose section in the interior cavity of the needle hub. 
         [0033]    The tip cover can be tethered to the needle hub. 
         [0034]    The tip cover can be tethered with a folded mechanism that is attached to a flange extending from the tip cover and to a heat weld nipple extending from the needle hub. 
         [0035]    The folded mechanism can be attached to a nose plate which is coupled to the tip cover. 
         [0036]    The nose plate can have a perimeter defining an opening having the tip cover projecting therethrough. 
         [0037]    The tip cover and the folded mechanism can be integrally formed. 
         [0038]    The tip cover can further comprise a flap extending proximally inside the tip cover from a distal end of the side opening, said flap being configured for preventing the needle tip from coming out of the side opening. 
         [0039]    The side opening can have a width larger than a diameter of the needle. 
         [0040]    A perimeter of the side opening and a perimeter of the opening is smooth to minimize friction between the needle and the tip cover. 
         [0041]    The tip cover can abut against the catheter hub in the ready to use position. 
         [0042]    The tip cover can further comprise a flap extending proximally inside the tip cover from a distal end of the side opening, said flap being configured for preventing the needle tip from coming out of the side opening. 
         [0043]    The method can further comprise providing an air vent housing attached to a proximal end of the needle hub, a closing cap attached to a proximal end of the air vent housing, and a filter sandwiched between the air vent housing and the closing cap. 
         [0044]    Aspects of the present disclosure include a ported catheter IV assembly that includes a ported catheter comprising a catheter hub, a catheter tube extending distally from a distal end of the catheter hub, and a valve positioned in an interior cavity of the catheter hub, and a needle hub unit comprising a needle hub having an interior cavity, a needle extending distally from the interior cavity of the needle hub, said needle extending through the valve and the catheter tube with a needle tip extending distally of a distal opening of the catheter tube in a ready to use position, and a needle guard coupled to the needle hub. 
         [0045]    The needle guard can comprise an elastic sleeve having a proximal end coupled to the needle hub, and a tip cover attached at a distal end of the sleeve. The sleeve is sleeved over at least a portion of the needle. The tip cover has an opening at a proximal end and a slotted hole. 
         [0046]    The needle extends through the sleeve, the opening of the tip cover, and the slotted hole of the tip cover in the ready to use position, and the needle tip is restrained inside the tip cover in a secured position. 
         [0047]    The ported catheter can further comprise a port cap assembly capping an injection port of the ported catheter. 
         [0048]    The sleeve can be elastic and compressible against a restoring force of the sleeve in the ready to use position. 
         [0049]    The sleeve can be attached to the needle hub via a ring fixed to the proximal end of the sleeve and the interior cavity of the needle hub. 
         [0050]    The tip cover can slide along the needle from the ready to use position to the secured position when the needle is retracted proximally from the ported catheter. 
         [0051]    The tip cover can be tethered to the needle hub via a folded mechanism. 
         [0052]    The folded mechanism can be tethered to a flange extending from the tip cover and a heat weld nipple extending from the needle hub. 
         [0053]    The folded mechanism can comprise a nose plate and a pair of legs extending from the nose plate to the needle hub, said nose plate defining a hole receiving the tip cover. 
         [0054]    The tip cover and the folded mechanism can be integrally formed. 
         [0055]    The tip cover further can comprise a flap extending proximally inside the tip cover from a distal end of the slotted hole, said flap being configured for preventing the needle tip from coming out of the slotted hole. 
         [0056]    The ported IV catheter assembly can further comprise an air vent housing attached to a proximal end of the needle hub, a closing cap attached: to a proximal end of the air vent housing, and a filter sandwiched between the air vent housing and the closing cap. 
         [0057]    Another aspect of the present disclosure includes a method of making a ported IV catheter assembly, the method comprising providing a ported catheter comprising a catheter hub, a catheter tube extending distally from a distal end of the catheter hub, and a valve positioned in an interior cavity of the catheter hub. 
         [0058]    The method can further comprise providing a needle hub unit comprising a needle hub having an interior cavity, a needle extending distally from the interior cavity of the needle hub, and a needle guard coupled to the needle hub, said needle guard comprising an elastic sleeve having a proximal end coupled to the needle hub, and a tip cover attached at a distal end of the sleeve, said tip cover having an opening at a proximal end and a slotted hole. 
         [0059]    The method can further comprise extending a needle tip of the needle through the elastic sleeve, the opening of the tip cover and out the slotted hole, the valve, and the catheter tube with the needle tip extending distally of a distal opening of the catheter tube in a ready to use position. 
         [0060]    The method can further comprise compressing the elastic sleeve against the catheter hub in the ready to use position. 
         [0061]    The method can further comprise confining the needle tip inside the tip cover in a secured position. 
         [0062]    The ported catheter can further comprise a port cap assembly capping an injection port of the ported catheter. 
         [0063]    The method can further comprise sliding the tip cover along the needle from the ready to use position to the secured position. 
         [0064]    The sleeve can be attached to the needle hub via a ring fixed to the proximal end of the sleeve and the interior cavity of the needle hub. 
         [0065]    The tip cover can be tethered to the needle hub via a folded mechanism. 
         [0066]    The folded mechanism can be tethered to a flange extending from the tip cover and a heat weld nipple extending from the needle hub. 
         [0067]    The folded mechanism can comprise a nose plate and a pair of legs extending from the nose plate to the needle hub, said nose plate defining a hole receiving the tip cover. 
         [0068]    The tip cover and the folded mechanism can be integrally formed. 
         [0069]    The tip cover can further comprise a flap extending proximally inside the tip cover from a distal end of the slotted hole, said flap being configured for preventing the needle tip from coming out of the slotted hole. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0070]    The various embodiments of the present safety needle assemblies and needle tip covers now will be discussed in detail with an emphasis on highlighting the advantageous features. These embodiments depict the novel and non-obvious safety needle assemblies and needle tip covers shown in the accompanying drawings, which are for illustrative purposes only. These drawings include the following figures, in which like numerals indicate like parts: 
           [0071]      FIG. 1  is an assembled isometric view of an embodiment of a safety IV needle assembly including a cannula assembly and a catheter assembly; 
           [0072]      FIG. 2  is an exploded perspective view of the cannula assembly and the catheter assembly of  FIG. 1 ; 
           [0073]      FIG. 3  is a partial perspective view of a needle guard with a tip cover and a sleeve; 
           [0074]      FIG. 4  is an assembled side cross-sectional view of the safety IV needle assembly of  FIG. 1 ; 
           [0075]      FIG. 5  is a partial cutaway perspective view of the safety IV needle assembly of  FIG. 1 ; 
           [0076]      FIG. 6  is a close up view of the safety IV needle assembly of  FIG. 5  in perspective and separated from the catheter hub; 
           [0077]      FIG. 7  is a perspective view of the needle hub unit removed from the catheter hub unit, such as following successful venipuncture, to show the needle guard shielding the needle tip; 
           [0078]      FIG. 8  is a cross-sectional side view of the needle hub unit in a shielded position; 
           [0079]      FIG. 9  is a close up view of circled region  9  of the needle hub unit if  FIG. 8 ; 
           [0080]      FIG. 10  is a close up view of a tip cover of the present disclosure; 
           [0081]      FIG. 11  is a perspective view of another embodiment of a tip cover of the cannula assembly; 
           [0082]      FIG. 12  is a close up view of a catheter assembly with a needle guard in accordance with an alternative embodiment; and 
           [0083]      FIG. 13  is a close up view of the needle guard of  FIG. 12  in a shielded position. 
       
    
    
     DETAILED DESCRIPTION 
       [0084]    The following detailed description describes the present devices, apparatuses, systems, and methods with reference to the drawings. In the drawings, reference numbers label elements of the present embodiments. These reference numbers are reproduced below in connection with the discussion of the corresponding drawing features. 
         [0085]    With reference now to Figures (“FIGS.”)  1  and  2 , an embodiment of an IV catheter assembly  10  is shown comprising a ported catheter or ported catheter unit  100  and a needle hub unit  200  detachably assembled to a proximal end of the ported catheter  100  in a ready to use position. In an example, the ported catheter unit  100  comprises a catheter hub  120  having a catheter body  121  and an injection port  124  extending from the catheter body  121 , a port cap assembly  125  capping the injection port  124 , a valve  150  ( FIGS. 3 and 4 ) can be disposed in the interior cavity  127  of the catheter body  121  to control or restrict the flow of fluids through the injection port  124  and through the proximal opening at a proximal end  126  of the catheter hub  120 , and a catheter tube  140  extending distally from a distal end  123  of the catheter hub  120 . 
         [0086]    Conventionally speaking, the distal end  123  of the catheter hub  120  is the end away from the practitioner, such as toward the tip of the catheter tube  140 , and the proximal end  126  is the end opposite the distal end, typically closer to the practitioner. In alternative catheter embodiments, the injection port  124  may be omitted. A distal end of the catheter tube  140  is configured for insertion into the patient and a proximal end of the catheter tube  140  can be attached to the catheter body  121  by a bushing  141 . The bushing  141  is attached at to the catheter body  121  at the distal end  123  thereof inside the interior cavity  127  to secure the catheter tube  140  to the catheter body  121 . The catheter hub  120  is configured for use with an intravenous tubing at a proximal end  126  thereof to facilitate delivery of fluids into the patient. For example, when the catheter  140  is inserted into the patient, solution such as saline solution and/or medication can flow from the proximal end  126  of the catheter hub  120  to the catheter tube  140  without leakage. Fluid samples can also be drawn from the patient through the proximal end  126  of the catheter hub  120 . In an example, the proximal opening of the catheter hub  120  is shaped as a female Luer, with or without external threads. As shown, proximal end of the catheter hub  120  has external threads for receiving a male Luer tip, such as a syringe tip or an IV adaptor, with or without a threaded collar for engaging the external threads. 
         [0087]    As shown, the catheter hub  120  has a hub lengthwise axis and the injection, port  124  has a port lengthwise axis that is generally perpendicular to and located off-axis to the hub lengthwise axis. In other words, the two angled axes do not intersect. In another example, the axis of the injection port  124  intersects the axis of the catheter hub  120 , such as being in-line, and preferably at a right angle therefrom, as further discussed below. An optional pair of wings  129  extends from the catheter body  121  for use to secure and stabilize the ported catheter unit  100  to the patient following catheterization. 
         [0088]    The interior cavity  127  of the catheter body  121  is selectively in fluid communication with the injection port  124  depending on the status or configuration of the valve  150 . The female Luer connector of the catheter hub is thus configured to matingly receive a male Luer connector, such as an IV line, a Luer access connector, a syringe tip, a vent plug, other known connectors, or future-developed IV devices. Each of these components can be sized and configured in conformity with at least some of the International Standards Organization (ISO) standards for female and male Luer connections under current or future standards. For discussion purposes, any one of these components or the class of these components may be referred to as a male medical implement. 
         [0089]    In an example, the catheter body  121  has a latching means for engaging with and removably securing the needle hub unit  200  to the catheter hub  120 . In an embodiment, the latching means comprises one or more recesses  122  formed on an exterior of the catheter body  121 , at or near the proximal end  126  of the catheter hub  120  to engage corresponding bumps or projections on the needle hub. The recesses and the bumps can be located in reversed order. In other embodiments, other engagement means, such as male or female detents, for removably attaching the needle hub unit  200  to the proximal end of the ported catheter  100 , are contemplated. 
         [0090]    With reference to  FIGS. 3 and 4 , the valve  150  is configured to seal the internal opening of the injection port  124  from the interior cavity  127  of the catheter body  121  and also seals the proximal opening  126  of the catheter body  121  to prevent flow through the valve  150  and through the catheter hub from the proximal opening of the catheter hub. In an example, the valve  150  is made from an elastomeric or a thermoplastic elastomer (TPE) material and includes two valve components or valve sections, namely a port valve  151  and an inlet valve  149  comprising a septum. The septum of the inlet valve  149  seals the proximal opening at the proximal end  126  of the catheter body  121  and opens into or leads into the interior cavity  127  of the catheter hub  120 . The elongated body of the port valve  151  is configured to occlude the internal opening of the injection port  124  from the interior cavity  127  to block fluid flow coming from or passing through the injection port  124 . Thus, the valve  150 , because it has a port valve  151  component and an inlet valve  149  component, may be referred to as a combination valve, a dual function valve, or a combined valve. In one example, the port valve  151  and the inlet valve  149  are unitarily formed as a one-piece valve  150 . In another example, the port valve  151  and the inlet valve  149  can be formed separately and subsequently joined or combined to form a single integrated valve  150 . For example, the port valve  151  and the inlet valve  149  can be welded, glued, or joined using a snap fit arrangement in which one component is slid into another component. The valve  150  may be made using an elastomer, a TPE, an elastic biocompatible material, or combinations thereof. In one example, the valve  150  is made from a silicone material. In some examples, a metallic spring or other biasing material may be incorporated with the valve  150  to facilitate opening and/or closing of the port valve  151 , the inlet valve  149 , or both valve components  151 ,  149 . When the valve  150  is formed from two or more different components, the different components can be made from different material properties, such as different material types and/or different durometers. 
         [0091]    The valve  150  has a generally cylindrical body extending between an open distal end and a proximal end with a septum. Internally, a bore permits fluid communication between the open distal end and the split septum of the inlet valve  149 . The split septum can be selectively opened to allow a flow path to flow between the distal and proximal ends. When positioned inside the interior cavity  127  of the catheter body  121 , the port valve  151  seals off the interface between the injection port  124  and the interior cavity  127  of the catheter body  121  by presenting a surface, when in the normal expanded state, that covers the internal opening at the interface between the injection port  124  and the interior cavity  127  to prevent fluid from entering the interior cavity  127  from the injection port  124 . The surface of the port valve  151  also prevents fluid from passing through the interior cavity  127  from either the distal end  123  or the proximal end  126  of the catheter body  121  from entering the lumen of the injection port  124 . The port valve  151  is sized and shaped to be received within the interior cavity  127  of the catheter body  121 , but can be sized slightly larger, such as larger in diameter, than the interior cavity  127  to provide a tight fit inside the interior cavity  127  and particularly at the opening between the injection port  124  and the interior cavity  127 . The septum at the port valve  151  is normally closed to prevent fluid from passing through the interior cavity of the catheter hub via the proximal opening of the catheter body. When the septum is activated, such as when pushed by a male medical implement, fluid is permitted between the proximal and distal ends of the catheter hub. 
         [0092]    The needle hub unit  200  comprises a needle hub  220 , and a needle  240  extending distally from the needle hub body  98 . The needle hub  220  comprises a blood flashback chamber and a vent plug, which is typically attached to the proximal end of the catheter hub. As shown in  FIGS. 3-6 , a needle guard  90  can be included to prevent needle stick injuries following successful venipuncture. In an example, the needle guard  90  comprises an elastic sleeve  260 . A tip cover  270  is attached to a distal end of the elastic sleeve  260  of the needle guard. The needle guard  90  can be positioned in a distal shroud  92  of the needle hub  220 . The distal shroud  92  can be a continuous cylinder or can comprise a slot, as show in  FIG. 2 . A ring  262  ( FIG. 5 ) can attach a proximal end of the sleeve  260  of the needle guard  90  to a distal nose section  94  located in the interior cavity  223  of the distal shroud  92  of the needle hub  220 . In an example, the ring  262  can attach to a coupling  96  which is attached to a proximal end of the elastic sleeve  260 . As shown, the coupling  96  can embody a conical shaped structure and the ring  262  can embody one of a male and female detents for engaging the other one of the male and female detents  222  on the distal nose section  94  of the needle hub  220 . The coupling  96  and the ring  262  can be integrally formed. 
         [0093]    The needle  240  extends through the distal nose section  94  of the needle hub body  98  and through the sleeve  260  and out the tip cover  270  to pass through the septum and the bore of the valve  150 , the catheter hub  120 , and the catheter tube  140  in a ready to use position, as shown in  FIG. 1  and partially in  FIGS. 5 and 6 . In the ready to use position, the catheter assembly  10  is ready for vascular access. The needle tip  245 , such as the beveled end, of the needle  240  extends distally of the opening at the distal end of the catheter tube  140  in the ready to use position. The tip cover  270  is configured to secure the needle tip  245  from accidental needle sticks following use. For example, the tip cover  270  is configured to prevent the needle tip  245  from puncturing through a membrane to expose the needle tip  245  after the needle tip is covered by the tip cover  270 , as further discussed below. In one embodiment, the flashback chamber of the needle hub  220  can be separately formed and subsequently attached to a distal needle hub portion. With reference to  FIGS. 3 and 4 , an air vent housing  227 can attach to a proximal end of the needle hub  220  and a closing cap  229  securing a filter  228  between the closing cap  229  and the air vent housing  227 . In one example, the needle hub body  98  includes a proximal cylinder sized and shaped to project into a bore of the air vent housing  227 . In some examples, the connection can reverse with the air vent housing having a cylinder sized and shaped to project into a bore of the needle hub body  98 . The connection between the needle hub body and the air vent housing can have an interference fit and can optionally be glued or welded together. In other examples, threaded engagement may be used to secure the two together. Raised projections or other surface features may be included with the air vent housing  227  to facilitate gripping. The closing cap  229  can couple to the air vent housing  227  in a similar manner. 
         [0094]    With reference again to the needle guard  90 , the elastic sleeve  260  can encase or cover the needle  240  when the needle  240  is withdrawn from the ported catheter unit  100 . The sleeve  260  can also capture blood to prevent spilling or droplets from falling on the ground or other surfaces. In one embodiment, the sleeve  260  is a long hollow tubular structure that is collapsible or compressible into random or defined folds to store elastic energy in the ready to use position. In one example, the sleeve  260  is made of an elastic material, such as a compressible syntactic rubber capable of storing elastic energy when compressed in the ready to use position. In another example, the sleeve  260  is made from a neoprene or isoprene material via transfer molding or injection molding. Other elastomer and thermoplastic elastomer materials are contemplated for making the sleeve  260 . 
         [0095]    With reference to  FIGS. 3, 5, and 6 , the proximal end of the sleeve  260  of the needle guard  90  is attached to the distal nose section  94  in the interior cavity  223  of the distal shroud  92  using a ring  262 . The ring  262  can snap into mating surfaces on the distal nose section  94 . In an example, the ring  262  has a conical shape for coupling to a conical shape distal nose section  94 . In other examples, the ring and the distal nose section can embody other shapes, such as being generally cylindrical. The proximal end of the sleeve  260  can attach to the ring  262  by mechanical means, such as clamping, fastening, or adhesive. In some example, the ring  262  is unitarily formed with the sleeve  260  and is made from the same material as the sleeve. The distal end of the sleeve  260  can attach to the tip cover  270 , which is further discussed below, by mechanical means, such as by clamping, fastening, or adhesive. In the ready to use position, the needle  240  projects through a side opening  274  of the cylinder of the tip cover  270  and causes the tip cover  270  to cant off-axis from the lengthwise axis of the needle guard  90 . As more clearly shown in  FIGS. 4 and 5 , the tip cover  270  is slanted and contacts the interior surface of the distal shroud  92  as well as the proximal end of the catheter hub. Under the elastic energy of the sleeve  260 , the tip cover  270  is urged to return to its normal linear in-line position but for the presence of the needle  240 . Thus, the tip cover  270 , when canted, exerts a force onto or against the needle  240  and vice versa. Accordingly, an aspect of the present disclosure is understood to include a needle guard comprising a compressible sleeve attached to a cylinder and wherein the needle guard has a lengthwise axis and wherein a side opening is provided on the cylinder at a location away from the lengthwise axis. In an example, the side opening can be tangent to the lengthwise axis of the needle guard. The cylinder can further comprise a distal end and wherein the distal end, at a location along the lengthwise axis of the needle guard, is solid. In another example, the distal end, at a location along the lengthwise axis of the needle guard, can comprise an opening but wherein a perimeter defining the opening is smaller in diameter than the diameter of the needle shaft. This arrangement allows the needle to only pass through the side opening  274 . 
         [0096]    From the position shown in  FIGS. 4-6  and following successful venipuncture, the needle  240  can be retracted away from the catheter hub  120 . During the retraction procedure, the tip cover  270  remains in contact with the proximal end of the catheter hub but the compressible sleeve  260  expands lengthwise as the needle retracts. Once the needle tip  245  moves proximally of the side opening  274  on the needle guard  90 , the stored elastic energy of the sleeve  260  is released and the tip cover  270  returns to its original configuration, in-line with the lengthwise axis of the needle guard, similar to that shown in  FIG. 3 . The needle  240  and the needle tip  245  are now positioned inside the sleeve  260  and the tip cover  270  and the needle device can be said to be in a protected position, shielded position, or secured position. 
         [0097]    Because the elastic sleeve  260  is compressed in the ready to use position and expands in the protected position to lengthen from a first length to a second length, which is longer than the first length, the sleeve  260  can act as a compression spring, which is compressed in the ready to use or first position and springs back to its original shape during needle  240  withdrawal towards the secured or second position. The elastic properties of the elastic sleeve  260  will allow the sleeve  260  to return to its original shape when the needle  240  is withdrawn and the needle tip moves proximally of the distal edge of the side opening and the tip cover  270  tilts back to an axis substantially in line with the lengthwise axis of the needle guard to secure the needle tip  245  inside the tip cover  270 . Thus, when the tip cover  270  is aligned with the needle  240 , the nose section  290  ( FIG. 5 ) of the tip cover  270  will un-bias away from the interior surface of the distal shroud  92  to cover the needle tip  245 . 
         [0098]    The sleeve  260  is understood to be movable or expandable during the retraction step of the needle away from the catheter tube and the catheter hub, such as following successful venipuncture. In an example, the needle hub can completely separate from the catheter hub as the needle retracts in the proximal direction and wherein the needle guard  90  continues to contact both the needle hub and the catheter hub. 
         [0099]    In the illustrated embodiment, a folded mechanism  250  is incorporated to act as a tether for the tip cover  270 , such as to prevent the sleeve  260  from being stretched too far and possibly tearing the sleeve or causing the sleeve to separate from the distal nose section  94  of the needle hub  220 . The folded mechanism  250  has a plurality of folded legs  253 , which are interconnected. The folded mechanism  250  can have a first end anchored to the needle hub  220  and a second end capturing, fixing, securing or engaging the tip cover  270 , thereby forming a restraint that limits the separation between the tip cover and the needle hub. In an example, a single folding mechanism  250  is incorporated as a tether. In another example, two folding mechanisms on two different sides of the sleeve  260  are used to provide the restraint. In an example, a nose plate  255  is used to attach to an end of each folded mechanism  250  with the other end of the folded mechanism attached to the needle hub. The nose plate  255  ( FIG. 6 ) has a perimeter defining a hole  252  therein for receiving the tip cover  270 . The folded mechanism  250  has one end extending from the nose plate  255  and another end attach to an anchoring point on the needle hub  120 , such as a nipple  226  extending from the catheter hub  120 . In the illustrated embodiment, folded mechanisms  250  extend proximally from the nose plate  255  and each comprising a hole  254  at the proximal free end attaching to a respective nipple  226  at opposite sides of the needle hub  220 . The legs  253  of the two folded mechanisms should be unyielding but able to fold over each other to occupy a small volume, such as inside the distal interior cavity  223  of the needle hub  200 . In some examples, the folded mechanisms  250  are single or multi-strand strings rather than folded legs. 
         [0100]    With reference again to needle guard  90  of  FIG. 3 , the tip cover  270  includes a hollow elongated body  275  and a nose section  273  formed at a distal end of the elongated body  275 . In an example, the elongated body  275  can be a cylinder and the nose section can be dome-shaped. One or more flanges  272  can extend laterally from or near a proximal end of the elongated body  275 , and a side opening  274  located off-axis from the lengthwise axis of the needle guard  90 . In one example, the side opening  274  is generally round. In another example, the side opening is oval or elliptical in shape. In yet other examples, the side opening is square, rectangle, or triangular in shape. Other shaped openings are contemplated, including non-symmetrical, random, polygonal, etc. The perimeter of the side opening can be smooth or radiused. A distal section or edge  292  of the perimeter of the side opening  274  can be recessed or positioned proximally of the distal tip  294  of the nose section  273 . 
         [0101]    When installed over a needle, the needle cannot project through the side opening when the tip cover  270  is in the normal in-line configuration of  FIG. 3 . The needle can pass through the side opening  274  when the tip cover  270  is canted or off-axis from the lengthwise axis of the needle guard  90 , as shown in  FIGS. 4-6 . Said differently, the tip cover  270  has a lengthwise axis that is common or in-line with the lengthwise axis of the needle guard  90 . When the axis of the tip cover is in-line, the needle cannot project through the side opening. When the axis of the tip cover is off-axis or not common with the lengthwise axis of the needle guard  90 , the needle can project through the side opening  274 . In one example, the side opening is formed only in the body or hollow cylinder  275  of the tip cover  270 . Thus, when the needle tip  245  is moved inside the tip cover  270 , the needle tip  245  is unable to exit the tip cover  270  through the side opening  274 , unless the tip cover  270  is manually tilted off-axis again. 
         [0102]    In an example, the width of the side opening  274  should be at least slightly larger than the diameter of the needle  240 . The length of the side opening  274  depends on the pitch or degree of tilt of the tip cover  270  when positioned inside the interior cavity  223  of the distal shroud  92  of the needle hub  220 . The tip cover  270  is configured to pass through the hole  252  of the nose plate  255  until the flanges  272  of the tip cover  270  abut against the nose plate  255  to prevent the tip cover  270  from passing completely through the hole  252  of the nose plate  255 . In another example, the elongated body  275  of the tip cover  270  tapers outwardly so that the diameter of the tapered portion restricts the amount of insertion of the tip cover  270  into the hole or opening  252  of the nose plate  255 . The tip cover  270  should be made of a material that is able to resist needle punctures. In one example, the tip cover  270  is made of metal material, such as stainless steel formed using a metal stamping process. In another example, the tip cover  270  is made of a rigid plastic such as POM or ABS. In still other examples, the tip cover  270  is made from an elastomeric material and has a metal insert, metal sleeve, or metal flange located at the distal tip  294  of the nose section  273 . For example, the metal insert, sleeve, or flange can be adhered to the inside surface of the nose section  273  or embedded into the nose section  273  by insert molding, as examples. The insert, sleeve, or flange can also be made from a hard plastic instead of a metal. 
         [0103]    With reference again to  FIGS. 4-6 , a sectional view of the catheter assembly  10  is shown with the needle hub  220  being generally cylindrical with a grip flange  219  extending laterally and outwardly from an outer surface of the needle hub  220 . A latching means, such as one or more bumps  224 , can be provided at a distal opening  221  of the distal shroud  92  of the needle hub  220  to engage the proximal end of the catheter hub  120  and latch the needle hub  220  to the catheter hub  120 . For example, the spaced apart bumps  224  can be incorporated to grip against the external threads, such as a shoulder or ledge of the threads, of the catheter hub  120  to retain the needle hub to the catheter hub. As previously mentioned, the bumps  224  can also engage corresponding recesses on the catheter hub. The grip flange  219  is configured to aid the user in inserting the needle  240  into a vasculature of a patient, and withdrawing the needle hub  220  from the catheter hub after successful venipuncture. 
         [0104]    The needle hub  220  has a first interior cavity  296  and a second interior cavity  225  located within the male projection  298  of the air vent housing  227 . The first interior cavity  296  and the second interior cavity  225  are in fluid communication with one another via an orifice or opening at an end of the male projection  298 . A proximal end of the needle  240  is in fluid communication with the first interior cavity  296  and the second interior cavity  225 . The needle  240  extends through the distal nose section  94 , through the needle guard  90 , and through the catheter unit  100  with the needle tip  245  extending out a distal end of the catheter tube  140 . 
         [0105]    Referring again to  FIG. 5 , a proximal end of the sleeve  260  is fixed to the ring  262  and the ring  262  can engage the undercut  222 , as previously discussed. The distal end of the sleeve  260  is secured to the tip cover  270 . For example, the coupling  96  and the tip cover  270  can be fixed to the sleeve  260  by adhesive, bonding and/or mechanical engagement. In an example, the sleeve  260  can be a compressible or collapsible hollow tube. The sleeve  260  can be made of an elastic material, such as a compressible syntactic rubber capable of storing elastic energy when compressed in the ready to use position. In some examples, exterior of the sleeve  260  is provided with pre-formed kinks or pleats so that the elastic sleeve  260  compressed along the kinks or pleats when in the ready to use position shown. In other examples, no kinks or pleats are provided and the elastic sleeve  260  simply compress in random folds. 
         [0106]    In the ready to use position, the needle hub  220  is removably attached to the catheter hub  120  by engaging the one or more bumps  224  of the needle hub  220  with the one or more recesses  122  defined in an outer surface of a proximal portion of the catheter hub  120 . The engagement between the needle hub  220  and the catheter hub  120  temporarily secures the needle hub  220  to the catheter hub  120 . In other examples, the bumps  224  simply rest against a shoulder or ledge on the external threads of the catheter hub to retain the needle hub to the catheter hub. The needle  240  passes through the compressible sleeve  260  and the tip cover  270  through the side opening  274  to the catheter unit  100 , where it then passes through the septum of the inlet valve  150  and out the port valve  151  located inside the catheter body  121  and out the catheter tube  140  with the needle tip  245  exposed. 
         [0107]    In the ready to use position, the tip cover  270  is tilted off-axis front the lengthwise axis of the needle guard  90  and abuts against the proximal end of the catheter hub  120  to maintain the sleeve in the compressed or collapsed state storing the elastic energy. The tip cover  270  also contacts the interior surface of the distal shroud  92  in the ready to use position. The air vent housing  227 , filter  228 , and closing cap  229  cooperatively allow gas to vent from the needle  240  after successful venipuncture has occurred. Once the needle  240  has successfully punctured a blood vessel of a patient, the blood enters the first interior cavity  296  and if necessary the second interior cavity  225  via the opening of the male projection  298 . The filter  228  can be a hydrophobic filter that allows air to vent but traps blood within the second interior cavity  225 . 
         [0108]    Referring again to  FIG. 6 , the tip cover  270  is tethered to the needle hub  220  via the folded mechanism  250 . In one embodiment, the hole  254  at the first end of each of the folded mechanism is placed over a nipple  226  on the needle hub  220  and optionally heat welded thereto to fix the first end of the folded mechanism  250  to the needle hub  220 . In other examples, the needle hub is provided with a hole and the folded mechanism is provide with a nipple or projection for engaging the hole. The second end or distal end of each folded mechanism  250  is attached to the nose plate  255  and/or a corresponding flange  272  on the tip cover  270 . 
         [0109]    In another embodiment, the folded mechanism  250  is integrally formed with the nose plate  255 . The nose plate  255  has a perimeter defining a hole  252  in a center thereof to receive the tip cover  270 , as previously discussed. The size or diameter of the hole  252  is slightly larger than the body portion  275  of the tip cover  270 , but less than a distance between opposite ends of the two flanges  272 . In another example, a single continuous flange is provided with the tip cover instead of spaced apart flanges. The nose  273  of the tip cover  270  extends through the hole  252  of the nose plate  255  until distal surfaces of the flanges  272  abut against the proximal surface of the nose plate  255 . The size of the hole  252  thus prevents the tip cover  270  from passing completely through the hole  252 . 
         [0110]    In yet another embodiment, slots can be formed with the nose plate  255  or the folded mechanism  250 , which acts as a tether, to accommodate the flanges  272  passing therethrough to secure the tip cover  270  to the nose plate  255 . 
         [0111]    In still yet another embodiment, the distal end of the folded mechanism  250  can attach directly to the tip cover  270  at the flange  272  or to the surface of the tip cover. The tether can also be integrally formed with the tip cover  270 , thereby eliminating the need for the nose plate  255  and/or the flanges  272 . 
         [0112]    After successful venipuncture and upon retraction of the needle hub  220  from the catheter hub  120 , the bumps  224  on the needle hub  220  disengage from the recess  122  of the catheter hub  120  and the sleeve  260  begins to expand as the needle hub  220  is withdrawn away from the catheter hub  120 . The tip cover  270  remains in abutting contact with the proximal end of the catheter hub. The tip cover  270  slides relative to the needle  240  as the elastic sleeve  260  releases its stored energy and the tip cover  270  moves relative to the needle  240  until the sleeve  260  is fully expanded and the needle tip  245  moves proximally of the distal edge or distal section  292  ( FIG. 3 ) of the side opening  274  and eventually inside the tip cover  270  to be shielded by the tip cover  270 , also called the secured position or shielded position. 
         [0113]      FIG. 7  shows the needle guard  90  in the shielded position and the needle tip located inside the tip cover  270 . The two folded mechanisms  250  are shown expanded to restrict further expansion by the sleeve  260 . Optionally only one folded mechanism  250  is used. Because the sleeve  260  is elastic, the folded mechanisms  250  prohibit a scenario where the tip cover  270  is moved distally by stretching the sleeve  260 . If stretching is allowed, the needle tip  245  can come in contact with the sleeve  260  and can puncture through the sleeve. The hard material of the tip cover  270 , or an insert made from a hard material placed at the tip cover as previously discussed, can prevent the needle tip  245  from puncturing through the tip cover  270 . 
         [0114]    Referring now to  FIGS. 8 and 9 , as the tip cover  270  moves distally under the elastic force of the sleeve  260  until the needle tip  245  slips through the side opening  274 , the tip cover  270  rotates back into an in-line position in which the axis of the tip over coaxially aligns with the lengthwise axis of the needle guard  90 . In this position, the needle  240  and needle tip  245  cannot easily exit through the side opening  274  without external manipulation. Therefore, the needle tip  245  is safely shielded inside the tip cover  270 , which does not have an opening in-line with the lengthwise axis of the needle guard for the needle tip to re-emerge. In another example, an opening is provided at a distal end of the tip cover and in-line with the lengthwise axis of the needle guard. However, if the opening is provided, the will have a smaller diameter than the diameter of the needle shaft to prevent the entire tip and large sections of the needle shaft from re-emerging out the tip cover. 
         [0115]    The embodiment of the tip cover  270  illustrated in  FIG. 10  has a hollow elongated body  275  with one or more flanges  272  and an opening  271  at a proximal end thereof, and a nose end  273  at a distal end of the elongated body  275 . The side opening  274  is configured to allow the needle to extend through both the proximal opening  271  and the side opening  274  when the tip cover  270  is in the ready to use position. That is, because the side opening  274  is at a side of the tip cover  270  away from the lengthwise axis of the tip cover  270 , the tip cover  270  should tilt and the side opening  274  at least partially aligned with the lengthwise axis of the tip cover for the needle to project therethrough. Further, because the tip cover  270  is connected to the sleeve  260 , when the tip cover is tilted, the sleeve  260  can be loaded with stored energy and will tend to straighten the tip cover  270  to a position of least resistance. There should be minimal friction between the needle  240  and the side opening  274  and proximal opening  271  of the tip cover  270  to ensure the tip cover  270  can slide along the needle  240  when moving to the secured position. In one example, a coating can be applied to reduce friction between the needle  240  and the tip cover  270 . In another example, the tip cover  270  can be made of a material that has a relatively low and suitable coefficient of friction. In yet another example, the contact surfaces with the needle  240 , such as around the side opening  274 , and the opening  271  are rounded, radiused, or smooth to minimize friction. 
         [0116]      FIG. 11  illustrates another embodiment of the tip cover  270  which is similar to the tip cover of  FIG. 10 , except that a flap  276  is provided along the distal section  292  of the side opening  274  and extends proximally into the interior cavity of the tip cover  270 . The flap  276  acts as a restriction and prevents or thwarts the needle tip  245  from extending back out the side opening  274  once the needle hub unit  200  is in the secured or shielded position. 
         [0117]    Referring to  FIG. 12 , the tip cover  270  of  FIG. 11  is shown positioned inside the distal shroud  92  of the needle hub  220  and is tilted to allow the needle  240  to pass through the side opening in the ready to use position. The flap  276  is shown and is configured so as not to interfere with the sliding of the tip cover  270  relative to the needle  240 . The flap  276  can be flexible or semi-rigid and configure to restrict the needle tip&#39;s ability to re-emerge out the side opening  274  after the shielded position. 
         [0118]    In the secured position shown in  FIG. 13 , the needle tip  245  is secured inside the tip cover  270 . The flap  276  helps prevent the needle from exiting the side opening  274 . Therefore, the needle tip  245  is safely secured in the tip cover  270 . 
         [0119]    Methods of making and of using the IV catheter assembly and their components described elsewhere herein are contemplated and are considered within the scope of the present disclosure. 
         [0120]    The above description presents various embodiments of the present invention, and the manner and process of making and using them, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains to make and use this invention. This invention is, however, susceptible to modifications and alternate constructions from that discussed above that are fully equivalent. Consequently, this invention is not limited to the particular embodiments disclosed. On the contrary, this invention covers all modifications and alternate constructions coming within the spirit and scope of the invention as generally expressed by the following claims, which particularly point out and distinctly claim the subject matter of the invention.