# Patent

## Title
Safety IV catheter assemblies

## Abstract

A safety IV catheter assembly is disclosed which includes a catheter assembly, a needle assembly and a needle guard assembly. The needle guard assembly includes a needle guard, a biasing member and a bushing. The bushing is slidably positioned about the needle and includes an inner diameter which is smaller than an enlarged diameter portion of the needle such that the needle cannot be withdrawn through the bore of the bushing.

## Background
RELATED APPLICATIONS
This application claims priority to and the benefit of under 35 U.S.C. §119 to U.S. Provisional Application Ser. No. 61/479,556 entitled SAFETY IV CATHETER filed on Apr. 27, 2011 and is incorporated by reference in its entirety for all purposes.


BACKGROUND
1. Technical Field
The present disclosure relates to intravenous (IV) catheter assemblies for accessing a body vessel, and more particularly to IV catheter assemblies including a safety device for protecting a clinician from accidental needle stick injuries.
2. Background of Related Art
Intravenous (IV) catheter assemblies are utilized in a variety of medical applications for supplying or withdrawing fluid to or from a body vessel. Generally, IV catheter assemblies include an external cannula for indwelling in a blood vessel of a patient and an internal needle that is inserted into the external cannula to facilitate piercing of the blood vessel of the patient. In operation of the IV catheter assembly, the internal needle is inserted into the external cannula such that the tip portion of the internal needle protrudes from a tip portion of the external cannula. Next, the internal needle is manipulated to pierce a blood vessel and to position the external cannula within the blood vessel. While the external cannula is positioned within in the blood vessel, the internal needle is withdrawn from the external cannula leaving the external cannula positioned within the blood vessel. In this position, a medical device can be connected to the rear end portion of the external cannula using, for example, a luer connector, to facilitate the supply and withdrawal of fluid, such as blood, medication and/or nutrients to or from the body vessel.
After the internal needle is withdrawn from the external cannula, the exposed needle tip of the internal needle creates a danger of accidental needle stick injury which can leave a clinician vulnerable to the transmission of various blood-borne pathogens, such as HIV and hepatitis. While needle tip protectors have been developed to protect the clinician from needle stick injuries, the cost, ease of use, and effectiveness of these needle tip protectors leaves room for improvement.
Accordingly, it would be beneficial to provide a safety IV catheter assembly which is easily activated by a clinician, effectively protects a clinician from accidental needle stick injury and is economical to produce.
SUMMARY
The present disclosure is directed to a safety IV catheter assembly which comprises a catheter assembly including a catheter hub defining a cavity and a catheter tube, a needle assembly including a needle hub and a needle having an enlarged diameter portion and a needle tip, and a needle guard assembly including a needle guard having a body portion including a proximal wall defining a guard bore and first and second legs extending distally from the proximal wall. At least one of the legs has a radially extending portion and the first and second legs are movable from an unguarded position wherein the needle is positioned between the first and second legs and a guarded position wherein the radially extending portion is positioned distally of the needle tip to obstruct distal movement of the needle. The needle guard assembly further includes a bushing defining a bushing bore dimensioned to be slidably positioned about the needle at a location proximally of the enlarged diameter portion. An inner diameter of the bushing bore is smaller than the outer diameter of the enlarged diameter portion of the needle to prevent passage of the enlarged diameter portion of the needle through the bushing bore. The outer diameter of the bushing is greater than the inner diameter of the guard bore to prevent withdrawal of the needle through the guard bore.
In one embodiment, the first and second legs define a recess dimensioned to receive the bushing such that the bushing bore is aligned with the guard bore to slidably receive the needle. The recess may be configured to limit axial movement of the bushing about the needle in relation to the needle guard.
In one embodiment, the radially extending portion of the first leg is positioned distally of the distal end of the second leg. In addition, the second leg may be configured and dimensioned to be in spaced relation to the needle as the needle is withdrawn from the catheter assembly and the needle guard moves from the unguarded position to the guarded position.
In one embodiment, the needle guard assembly includes a biasing member positioned to urge the needle guard towards the guarded position. The needle guard may also be formed of a resilient material, wherein the needle guard is in an unbiased state in the guarded position. The biasing member may include an annular, resilient band.
In one embodiment, the needle guard includes an engagement arm which extends distally from the proximal wall and is configured to releasably engage the catheter hub.
In other embodiments, the first and second legs define an annular recess configured to receive the biasing member.
The first and second legs may define an undulating surface, wherein each of the undulating surfaces defines a radially extending portion.



BRIEF DESCRIPTION OF THE DRAWINGS
Various embodiments of the presently disclosed safety IV catheter assembly will be described herein with references to the accompanying drawings, wherein:
FIG. 1 is a side perspective view with parts separated of one embodiment of the presently disclosed safety IV catheter assembly;
FIG. 1A is a side cross-sectional view of the safety IV catheter assembly shown in FIG. 1 in an assembled configuration;
FIG. 1B is a rear end view of the safety clip of the safety IV catheter assembly shown in FIG. 1;
FIG. 2 is a side view of the safety clip and distal end of the needle of the safety IV catheter assembly shown in FIG. 1 with the needle tip in an unguarded position and the biasing member shown in cross-section;
FIG. 3 is a top view of the safety clip and needle shown in FIG. 2 with the needle in a guarded position and the biasing member shown in cross-section;
FIG. 4 is a side view of the safety clip and distal end of the needle of the safety IV catheter assembly shown in FIG. 1 with the needle tip in the guarded position and the biasing member shown in cross-section;
FIG. 4A is a side, cross-sectional view of the safety IV catheter assembly shown in FIG. 1A with the needle tip withdrawn into the safety clip in a guarded position;
FIG. 5 is a side, cross-sectional view of an alternate embodiment of the presently disclosed safety IV needle assembly with the needle tip withdrawn into the safety clip in the guarded position; and
FIG. 6 is a perspective view of the safety clip of the safety IV catheter assembly shown in FIG. 5.



DETAILED DESCRIPTION OF EMBODIMENTS
Embodiments of the presently disclosed safety IV catheter assembly will now be described in detail with reference to the drawings wherein like reference numerals designate identical or corresponding elements in each of the several views. In this description, the term “proximal” is generally used to refer to the portion of the device that is closer to a clinician, while the term “distal” is generally used to refer to the portion of the device that is farther from the clinician.
FIG. 1 illustrates one embodiment of the presently disclosed safety intravenous (IV) catheter assembly shown generally as 10. Safety IV catheter assembly 10 includes a catheter assembly 12 including a catheter hub 14 and a catheter tube 16 extending distally from catheter hub 14, a needle assembly 18 including a needle hub 20 (FIG. 1A) and a needle 22 extending distally from needle hub 20, and a needle guard assembly 24 including a needle guard 26, a biasing member 28, and a bushing 30.
Referring to FIGS. 1 and 1A, needle 22 of needle assembly 18 includes a needle tip 22a and an enlarged diameter portion 32. Enlarged diameter portion 32 may be formed on needle 22 by crimping. Alternately, the enlarged diameter portion 32 may be formed on needle 22 using other known techniques including welding a ring or bead onto or about the needle 22. Needle 22 defines a fluid channel 34 which communicates the distal end of the needle 22 with the needle hub 20.
Catheter hub 14 includes a body 36 defining a cavity 38 (FIG. 1A) having an open proximal end 38a and a distal end 38b which communicates with a fluid channel 40. Channel 40 communicates with catheter tube 16 such that catheter tube 16 is in fluid communication with cavity 38 of body 36 of catheter hub 14.
Body 36 includes a radial protrusion 42 which is positioned on a central portion of body 36 at a location to be engaged by a clinician's finger as will be discussed in further detail below. A proximal end of body 36 includes structure 48 for engaging a medical device. In one embodiment, the engagement structure includes a luer connector 50 or the like.
As shown in FIGS. 1-2, needle guard assembly 24 is formed from a resilient material and includes needle guard 26, biasing member 28 and bushing 30. Needle guard 26 includes a split body portion 60 which defines a first leg 60a and a second leg 60b which extend distally from a proximal wall 62. Proximal wall 62 defines a proximal throughbore 64 (FIG. 1B). A projection 73 extends proximally from proximal wall 62 and is dimensioned to be received within a recess (not shown) formed in a distal face of the needle hub 20 to properly orient the needle hub 20 and the guard. A resilient engagement arm 66 is spaced from body portion 60 and extends distally from proximal wall 62 and is angled towards body portion 60. See FIG. 1A. A distal end of arm 66 includes a radially extending protrusion 68 which is positioned to be received in a recess 70 (FIG. 1A) formed in catheter hub 14 to releasably secure needle guard 26 to catheter hub 14 as will be discussed in further detail below. A locator arm 71 is also provided and extends distally from proximal wall 62. The locator arm 71 is located in diametrical opposition to engagement arm 66 and is positioned to be received within a channel 72 (FIG. 1) formed through luer connector 50 of catheter hub 14 to properly orient the needle guard 26 within the cavity of the catheter hub as will be discussed in further detail below. Similarly, engagement arm 66 is also positioned to extend through a separate channel 72 formed through luer connector 50 to assist in properly orienting needle guard 26 in relation to catheter hub 14.
Needle guard 26 defines a centrally located recess 80 between first leg 60a and second leg 60b. The recess 80 is dimensioned to receive the bushing 30 such that a bore 30a defined through bushing 30 is aligned with the proximal throughbore 64 in the proximal wall 62 of needle guard 26. Recess 80 may be dimensioned to axially contain or limit axial movement of bushing 30 in relation to safety clip 26. Bore 30a of bushing 30 and throughbore 64 of proximal wall 62 of needle guard 26 are dimensioned to slidably receive needle 22 but to prevent passage of enlarged diameter portion 32 of needle 22. More specifically, the inner diameters of bore 30a and throughbore 64 are larger than the outer diameter of needle 22 but smaller than the outer diameter of enlarged diameter portion 32 of needle 32. In addition, the outer diameter of bushing 30 is greater than the inner diameter of throughbore 64 of proximal wall 62 of needle guard 26. Bushing 30 may be formed of any material having sufficient strength to engage the enlarged portion of the needle tip and to provide sufficient slip as the needle moves through the bushing bore. In one embodiment, the busing may be formed of a metal, such as stainless steel.
First leg 60a of needle guard 26 extends distally beyond second leg 60b and includes a radially extending portion 84. In one embodiment, radially extending portion 84 extends to a position distally of a distal end of second leg 60b when needle guard 26 is in guarded state (FIG. 4), i.e., in the state where the first leg 60a is not biased outwardly by needle 22 extending through the needle guard 26 and rather is moved inwardly by the inherent resilience of the needle guard 26 and the biasing member 28 as will be discussed in further detail below. Alternatively, the radially extending portion 84 need only extend radially a distance sufficient to prevent distal movement of the needle tip past the radially extending portion 84 after the needle tip 22a has been withdrawn into the needle guard 26 to the guarded position (FIG. 4).
As illustrated in FIGS. 1 and 1A, the second leg 60b of the needle guard 26 includes a distal end 90 which is spaced proximally of radially extending portion 84 of first leg 60a and defines a concavity 90a. The inner surface of second leg 60b is configured to be spaced from needle 22 to minimize the drag on the needle 22 during withdrawal of the needle 22 from catheter assembly 12. The length of second leg 60b should be such that when the needle 22 is fully retracted, the needle tip 22a extends distally of distal end 90 of second leg 60b. See FIG. 3.
First and second legs 60a and 60b define an annular recess 94 which is configured to receive biasing member 28. Although biasing member 28 is illustrated as a resilient, annular band, other biasing member configurations are envisioned. For example, the first leg 60a may include an embedded resilient strip formed of spring steel or the like to enhance the resilience of leg 60a. 
Referring to FIGS. 1A and 2, one or more guide walls 96 may be provided on one or both of legs 60a and 60b to prevent needle 22 from becoming misaligned with needle guard 26. As illustrated, guide wall 96 is positioned on the first leg 60a to extend along a side of needle 22 at a position spaced from needle 22. Additional guide walls 96 may be provided to retain needle 22 and tip 22a in a guarded position between legs 60a and 60b. 
Referring to FIG. 1A, in an assembled state, the needle guard 26 is supported on the proximal end of the catheter hub 14 such that the body portion 60 is positioned within cavity 38 and the proximal wall 62 of needle guard 26 is positioned adjacent to a proximal surface 14a of the catheter hub 14. With the body portion 60 of needle guard 26 positioned in cavity 38, engagement arm 66 and locator arm 71 extend through channels 72 in luer connector 50. Locator arm properly aligns needle guard 26 with catheter hub 14 and engagement arm 66 releasably secures needle guard 26 to catheter hub 14 via engagement of protrusion 68 within recess 70 of catheter hub 14.
In the assembled state, needle 22 extends through throughbore 64 (FIG. 1B) of proximal wall 62 of needle guard 26, between first and second legs 60a and 60b, and through the catheter assembly 12 such that the needle tip 22a extends from a distal end of catheter tube 16. In this position, the radially extending portion 84 of the first leg 60a is deflected outwardly from its unbiased position via engagement with the needle 22 such that the needle 22 passes between legs 60a and 60b. As discussed above, in one embodiment, the second leg 60b is spaced from the needle 22 to minimize any drag on the needle 22. As clearly shown in FIGS. 1A and 2, biasing member 28 is positioned about legs 60a and 60b of safety clip to urge the legs 60a and 60b towards each other to a guarded position. In an alternative embodiment, the biasing member may not be provided such that only the inherent resilience of the leg 60a urges leg 60a towards the guarded position (FIG. 4).
Referring to FIGS. 3-4A, when the needle 22 is withdrawn from the catheter assembly 12 such that the needle tip 22a passes proximally of radially extending portion 84, the inherent resilience of the leg 60a and/or the urging of the biasing member 28 causes the leg 60a to move inwardly towards leg 60b to position radially extending portion 84 distally of needle tip 22a of needle 22. In this position, the radially extending portion 84 prevents distal movement of needle 22 in relation to needle guard 26. In addition, as needle 22 is withdrawn through needle guard 26, enlarged diameter portion 32 of needle 22 engages bushing 30 as the needle 22 slidably moves through the bore 30a of bushing 30 and through throughbore 64 (FIG. 1B) in proximal wall 62 of needle guard 26, to effect proximal movement of bushing 30 towards proximal wall 62. When bushing 30 engages proximal wall 62, further proximal movement of needle 22 in relation to needle guard 26 is prevented. More specifically, because the enlarged diameter portion 32 of needle 22 has a diameter greater than the inner diameter of bore 30a of bushing 30, and the outer diameter of bushing 30 is greater than the inner diameter of throughbore 64 in the proximal wall 62 of needle guard 26, further proximal movement or withdrawal of needle 22 from needle guard 26 is prevented when bushing 30 engages proximal wall 62. As such, when bushing 30 engages proximal wall 62 and radially extending portion 84 of leg 60a is positioned distally of needle tip 22a, the needle tip 22a is retained in a guarded position within the needle guard 26. As shown in FIGS. 3 and 4, in the guarded position, the distal end of the needle tip 22a extends distally beyond the distal end of the leg 60b. Alternately, needle tip 22a can be positioned proximally of the distal end of leg 60b in the guarded position. Bushing 30 may be formed of any material having sufficient strength to engage the enlarged portion of the needle tip and the proximal wall and to provide sufficient slip as the needle moves through the bushing bore. In one embodiment, the busing may be formed of a metal, such as stainless steel.
Referring to FIGS. 5 and 6, in an alternative embodiment of the presently disclosed safety W catheter assembly shown generally as 100, the needle guard 126 is substantially similar to needle guard 26 except that the configuration of legs 160a and 160b of body 160 has been changed. More specifically, needle guard 126 includes a split body portion 160 including legs 160a and 160b. Legs 160a and 160b each define an undulating surface 170a and 170b, respectively. Each undulating surface 170a and 170b includes a radially extending portion 172. Each radially extending portion slidably engages the needle 122 when the needle 122 is positioned through the needle guard 126. When the needle 122 is positioned through the needle guard 126, legs 160a and 160b are deflected outwardly to facilitate passage of the needle 122. When the needle tip 122a is withdrawn through the needle guard 126 to a position in which the needle tip 122a is positioned proximally of the radially extending portions 172, such as shown in FIG. 5, the radially extending portions 172 are positioned to block distal movement of the needle 122. In all other respects, needle guard 126 functions in the same manner as needle guard 26.
Persons skilled in the art will understand that the devices and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary embodiments. It is envisioned that the elements and features illustrated or described in connection with one exemplary embodiment may be combined with the elements and features of another without departing from the scope of the present disclosure. As well, one skilled in the art will appreciate further features and advantages of the disclosure based on the above-described embodiments. Accordingly, the disclosure is not to be limited by what has been particularly shown and described, except as indicated by the appended claims.

## Claims

1. A safety IV catheter assembly comprising:
a catheter assembly including a catheter hub and a catheter tube, the catheter hub defining a cavity;
a needle assembly including a needle hub and a needle, the needle having an enlarged diameter portion and a needle tip; and
a needle guard assembly including a needle guard having a body portion including a proximal wall defining a guard bore and first and second legs extending distally from the proximal wall and defining a recess, at least one of the legs having a radially extending portion, the first and second legs being movable from an unguarded position wherein the needle is positioned between the first and second legs and a guarded position wherein the radially extending portion is positioned distally of the needle tip to obstruct distal movement of the needle, the needle guard assembly further including a bushing defining a bushing bore dimensioned to be slidably positioned about the needle within the recess at a location proximally of the enlarged diameter portion, an inner diameter of the bore of the bushing being smaller than the outer diameter of the enlarged diameter portion of the needle to prevent passage of the enlarged diameter portion of the needle through the bushing bore, wherein the outer diameter of the bushing is greater than the inner diameter of the guard bore to prevent withdrawal of the needle through the guard bore.

2. The catheter assembly of claim 1, wherein the bushing bore is aligned with the guard bore to slidably receive the needle.

3. The catheter assembly of claim 2, wherein the recess is configured to limit axial movement of the bushing about the needle in relation to the needle guard.

4. The catheter assembly of claim 2, wherein the radially extending portion of the first leg is positioned distally of the distal end of the second leg.

5. The catheter assembly of claim 1, wherein the second leg is configured and dimensioned to be in spaced relation to the needle as the needle is withdrawn from the catheter assembly and the needle guard moves from the unguarded position to the guarded position.

6. The catheter assembly of claim 1, wherein the needle guard assembly includes a biasing member positioned to urge the needle guard towards the guarded position.

7. The catheter assembly of claim 1, wherein the needle guard is formed of a resilient material, the needle guard being in an unbiased state in the guarded position.

8. The catheter assembly of claim 6, wherein the biasing member includes an annular, resilient band.

9. The catheter assembly of claim 1, wherein the needle guard includes an engagement arm which extends distally from the proximal wall and is configured to releasably engage the catheter hub.

10. The catheter assembly of claim 6, wherein the first and second legs define an annular recess configured to receive the biasing member.

11. The catheter assembly of claim 1, wherein the first and second legs each define an undulating surface.

12. The catheter assembly according to claim 11, wherein each of the undulating surfaces defines one of the radially extending portions.