HK1115734B - Method of making a needle shielding device - Google Patents

Description

Method of manufacturing a needle shield

Cross Reference to Related Applications

The present invention claims priority from the following provisional applications, and these provisional applications are incorporated herein by reference:

60/659226-Shield Apparatus for Locking onto a Needle-applied date 3, 7/2005;

60/659217-Needle shield Apparatus with Tubular Needle cover-applied for 3/7/2005;

60/659213-Needle Shield Apparatus with Tether to Needle hub-application date 3/7/2005;

60/714954-Blood Collection Device with Needle Shield-application date 9/7/2005.

Background

The present application relates to medical devices that use needles, such as spinal needles, intravenous catheter introducers, blood collection devices, and syringes. It includes methods of making needle-based devices and needle shields for such devices.

Disclosure of Invention

The present invention includes a method of making a needle assembly. The needle has a proximal end, a sharp distal end, and a longitudinal axis. The needle shield assembly is provided with an occlusion carrier, an occlusion (preferably a ball) and a lumen coaxial with the longitudinal axis of the needle. The lumen has a proximal end and a distal end. The blocking object is movable from a shielding position, in which the blocking object at least partially blocks the lumen, to a non-shielding position, in which the needle is slidable along the lumen. The stopper is disposed in the stopper carrier and in a shielding position. The proximal end of the needle is inserted into the distal end of the lumen and the needle shield assembly is moved such that the needle moves the blocking object from the shielding position to the non-shielding position.

A spring is mounted on the blocking object carrier such that the spring biases the blocking object towards the longitudinal axis of the needle. When the device is a catheter introducer assembly, the catheter is threaded over the needle. The catheter adapter snaps onto the needle shield assembly. At least a portion of the needle shield assembly is disposed within the catheter adapter. The obstruction is preferably a small ball, but may also be an aspherical object, such as a roller.

In the shielding position, the blocking object carrier preferably holds the blocking object in a position offset from the longitudinal axis of the needle. At least a portion of the needle shield assembly is disposed within the catheter adapter.

A method of manufacturing a catheter introducer assembly is also described. The polymer tube is extruded and mounted on the needle hub so that it slides relative to the needle hub. The catheter assembly is placed over the needle. In yet another method of the present invention, a second polymeric tube is extruded and secured over the catheter hub. The first and second polymer tubes are concentric. The step of extruding the polymeric tube may include providing a reinforcement in the polymeric tube. The polymer tube and the reinforcement may be co-extruded.

Another method includes extruding a polymeric tube, securing a needle hub and a needle to a distal end of the polymeric tube, and disposing a catheter assembly over the needle. The polymer tube has a second substantially parallel polymer tube such that the polymer tube includes a plurality of lumens.

These and other features of the present invention will be described in more detail below.

Drawings

FIGS. 1A, B and C are cross-sectional views showing an embodiment of the present invention when used in a catheter introducer;

FIG. 2 is a cross-sectional view through the needle shield in the deployed position;

FIG. 3 is a vertical cross-sectional view showing the angle between the needle bevel and the shield wall

FIG. 4 is a vertical cross-sectional view through the catheter introducer assembly with the needle shield in the non-deployed position;

FIG. 5 is a vertical cross-sectional view through the catheter introducer assembly with the needle shield in the deployed position;

FIG. 6 is an isometric cross-sectional view through the catheter introducer assembly with the needle shield in the non-deployed position;

FIG. 7 is an isometric cross-sectional view through the catheter introducer assembly with the needle shield in the deployed position;

FIG. 8 is an exploded view of the components of the needle shield and needle hub;

FIG. 9 is a vertical cross-sectional view through the catheter introducer assembly with the needle shield in the non-deployed position;

FIG. 10 is a vertical cross-sectional view through the catheter introducer assembly with the needle shield in the deployed position;

FIG. 11 is an isometric cross-sectional view through the catheter introducer assembly with the needle shield in the non-deployed position;

FIG. 12 is an isometric cross-sectional view through the catheter introducer assembly with the needle shield in the deployed position;

FIG. 13 is an exploded view of the components of the needle shield and needle hub;

FIG. 14 is an isometric view of an extruded polymeric tube for use in one embodiment of the present invention;

FIG. 15 is a vertical cross-sectional view through the catheter introducer assembly with the needle shield in the non-deployed position;

FIG. 16 is a vertical cross-sectional view through the catheter introducer assembly with the needle shield in the deployed position;

FIG. 17 is an isometric cross-sectional view through the catheter introducer assembly with the needle shield in the non-deployed position;

FIG. 18 is an isometric cross-sectional view through the catheter introducer assembly with the needle shield in the deployed position;

FIG. 19 is an exploded view of the components of the needle shield and needle hub;

FIG. 20 is an isometric view of a catheter introducer with a needle shield where the shield housing is made from an extruded polymer tube;

FIG. 21 is a cross-sectional view through the housing of the embodiment of FIG. 20;

FIG. 22 is a vertical cross-sectional view of the housing of the embodiment of FIG. 20;

FIG. 23 is a vertical cross-sectional view through the indicator needle shield with the needle shield in the non-deployed position;

FIG. 24 is a vertical cross-sectional view through the indicator needle shield with the needle shield in the deployed position;

FIG. 25 is an isometric cross-sectional view of the indicator needle shield with the needle shield in the non-deployed position;

FIG. 26 is an exploded view of the components of the syringe needle shield;

FIGS. 27-30 are isometric views of a winged catheter introducer equipped with a needle shield;

FIGS. 31-32 are isometric views of a winged catheter introducer equipped with a needle shield;

FIGS. 33-34 are isometric views of a needle shield for a Huber needle for an implantable access port;

FIG. 35 is an isometric view of a blood collection device with a needle shield;

fig. 36-51 are vertical views of alternative embodiments of the present invention.

Detailed Description

Embodiments of the invention will now be described when used with a catheter introducer, syringe or other needle-based device. It is not intended to limit the scope of the invention.

The present invention may be used with a variety of needle-based devices such as catheter introducers, syringes, winged needles and Huber needles. In almost all cases, shielding the needle involves providing a needle shield and ensuring that it does not come off the sharp distal end of the needle or move proximally to re-expose the sharp distal end. Thus, some types of locking mechanisms must prevent distal and proximal movement of the shield once the needle is shielded.

In the present invention, proximal movement of the shield is prevented by the assembly of fig. 1A, B and C and fig. 2. The assembly 1 includes a needle 10, the needle 10 having a longitudinal axis 11, an outer surface 12 and a sharpened distal end 15. Needle shield assembly 90 has an inner lumen 93, inner lumen 93 being coaxial with needle 10. Needle shield assembly 90 is shown inside catheter adapter or hub 23 of fig. 1A. The shield assembly 90 is comprised of a first housing 95, the first housing 95 being covered by a cap 100. The first housing 95 has a stepped area of reduced diameter 105 over which the spring 2 is threaded. First housing 95 has an opening 18 which, together with first housing 95, forms a holder or carrier 16 for ball 3 (shown in fig. 1A and 4). Opening 18 extends through outer wall 19 to lumen 93. Opening 18 is configured such that ball 3 can move therein, but ball 3 is restricted from moving radially, longitudinally, and circumferentially relative to axis 11.

In the non-shielding position of fig. 1A, the ball 3 protrudes through the hole 21 in the cap 100. The spring 2 exerts a force on the ball 3 which has an axial component and a component directed radially towards the axis 11. In the non-shielding position, ball 3 is in contact with outer surface 12 of needle 10. Thus, the biasing force of the spring 2 will cause the ball 3 to move towards the axis 11.

Shield assembly 90 approaches distal end 15 as it slides along needle 10. When the bevel of needle 10 passes ball 3, the biasing force in spring 2 presses ball 3 at least partially into lumen 93, and it moves away from hole 21 and radially in opening 18 toward axis 11. Due to the geometry of opening 18, ball 3 is at least partially within lumen 93 as the bevel passes. The axis 24 of the ball 3 is offset from the axis 11. The radial movement of the ball 3 is limited by the spring 2 and the top wall 20 of the cap 100. The axial movement of the ball is limited by the front wall 22 of the opening 18. Distal movement of needle 10 presses ball 3 against wall 22. When shield 90 is now slid proximally (i.e. needle 10 is slid distally), needle 10 will be blocked by ball 3, ball 3 being at least partially within lumen 15, and movement of the ball being limited by spring 2 and walls 20, 22.

Referring to fig. 3, wall 20 of cap 100 (tangent to ball 3) forms an angle a when ball 3 moves to its position at least partially occluding lumen 93. The angle alpha is set to a value less than the minimum bevel angle beta of needle tip 15. In the embodiment described herein, the angle between wall 20 and ball 3 is about zero degrees. When this angle is too large relative to angle beta, ball 3 will not be jammed.

The above operation will be described in more detail, with slight variations in the remainder of the description (with respect to catheter introducers, syringes, and other needle-based medical devices). Here three catheter introducers are shown. In the first, distal movement of the needle shield away from the sharp end of the needle is limited by abutment between the needle shield and a discontinuity on the introducer needle. In the second, the needle shield is at the end of the tubular member, and distal movement of the needle shield is limited by abutment with a member mounted on the needle hub. In a third, the needle shield is tethered to the needle hub, thereby preventing distal movement of the needle shield away from the sharp end of the needle. This is also used in syringes. In all cases, proximal movement and therefore retraction of the needle to expose the sharp end of the needle will be prevented by the above-described means.

The invention will now be described when used with a first type of catheter introducer assembly wherein distal movement of the needle shield assembly is limited by discontinuities, such as bumps or folds, on the needle. Reference is now made to fig. 4-8.

The purpose of the catheter introducer assembly 5 is to pierce a human or animal body through a needle, create an opening, insert a catheter into the opening and then remove the needle. To prevent the transmission of infectious diseases through a needle stick, the tip of the needle should be shielded once it is removed.

The body is pierced by the needle 10. Needle 10 has an outer surface 12, a proximal end 15, a distal end 20, and a lumen 22. Distal end 20 has a sharp tip or point 25. The distal end is tilted. Shown as having two sloped surfaces, surfaces 30 and 40 forming ramps extending in a proximal direction from sharp point 25. More or fewer than two ramps may also be used. Proximal end 15 is secured to needle hub 45. Needle 10 has an area of enlarged cross-section 14 located near distal end 20. The enlarged cross-section may be in the form of an annular ring, enlarged needle 10 diameter, segmented ring or discontinuity, bump or fold on the needle. The enlarged cross-section may be formed on needle 10 by crimping, grinding, deforming or depositing material on the surface of the needle. The difference between the diameter of needle 10 and its enlarged cross-section is very small (about 0.004 inches) and its length is only about 0.03 inches.

Catheter assembly 50 has a catheter hub 52, with catheter hub 52 having a proximal end 55, a distal end 60, and a lumen 70 extending therebetween. A catheter 65 extends distally away from distal end 60. Needle 10 is in lumen 70 of catheter assembly 50 prior to insertion into the body. Once needle 10 is inserted into the patient with catheter 65, needle 10 is withdrawn by pulling in a proximal direction. Catheter hub 52 has an inner surface 80 and an outer surface 82. The inner surface 80 is provided with a circumferential groove 75, the purpose of which groove 75 will be described appropriately. A single concave portion, indentation, circumferential ridge or convex portion will serve the same purpose as the circumferential groove.

Needle shield assembly 90 is enclosed in two mating components, namely a first housing 95 and a second housing or cap 100. Needle assembly housing 90 may be fitted into catheter hub 50. First housing 95 has a distal end 97 and a proximal end 99. Extending between the proximal and distal ends is a lumen 93, the lumen 93 being sized to allow the first housing 95 to slide axially and rotate on the needle 10. Stepped region 105 extends from proximate distal end 97 toward proximal end 99. The stepped region 105 is a reduced diameter region that enables the coil spring 110 to be disposed on the first housing 95. The spring 110 is a compression spring that applies an axial force in the proximal and distal directions. Other types of springs, such as a reed (see fig. 41) or a corrugated spring washer (see fig. 42), may also be used.

Toward distal end 97 of first housing 95 (but still in stepped region 105), first housing 95 is provided with an opening 120, opening 120 being sized to receive ball 122. The second housing or cap 100 has a proximal end 130 and a distal end 135. Proximal end 130 is provided with an opening 140, which opening 140 is sized such that it is slightly larger than the diameter of needle 10, but slightly smaller than the diameter of enlarged cross-sectional area 14. In this way, the second housing can slide axially along the needle from the proximal end 15 towards the distal end 20 until its opening 140 abuts the enlarged cross-sectional area 14, at which point it cannot slide further in the distal direction. When the first and second housings 95 and 100 are assembled, the second housing 100 covers most of the first housing 95 except for the distal end 97 of the first housing. Thus, the second housing 100 covers the spring 110. Second housing 100 is provided with an opening 150, opening 150 being sized such that a portion of ball 122 protrudes therethrough into slot 75.

When needle shield assembly 90 is in catheter hub 52 prior to deployment, a portion of ball 122 protrudes through opening 150 and is in groove 75. This locks needle shield assembly 90 to catheter hub 52 while allowing catheter hub 52 to rotate relative to needle shield assembly 90 depending on the extent of groove 75 (i.e., whether the groove is circumferential or only limited movement is possible because it does not extend around the entire inner circumference of the catheter hub). A portion of ball 122 is also in lumen 93 of first housing 95 and abuts outer surface 12 of needle 10 (i.e., ball 122 contacts outer wall 12 of needle 10). Needle 10 and shield assembly 90 are able to slide and rotate relative to each other with very low friction. Ball 122 is radially constrained by groove 75 and needle 10. Thus, needle shield assembly 90 is locked in catheter hub 52. Spring 110 exerts a force axially on ball 122 in a distal direction. Moreover, needle 10 abutting ball 122 will radially restrain ball 122 and prevent it from exiting groove 75.

Once catheter tube 65 is placed in the patient, needle 10 is pulled in a proximal direction (i.e., needle shield assembly 90 is moved toward tip 25 of needle 10). When first bevels 30 and 40 are facing ball 122 and then when first bevel 40 is aligned with ball 122, ball 122 is less radially constrained by needle 10 and is urged by spring 110, which begins to move distally and radially into opening 120. Ball 122 thus exits opening 150 and slot 75 and further enters radially inward into lumen 93 of shield assembly 90, pivots about edge 155 (the wall of opening 150 in second housing 100), and slides distally along the length of opening 120. As needle 10 continues its proximal movement, it is no longer radially constrained and ball 122 moves completely out of groove 75. When ball 122 is positioned such that edge 155 is above it, ball 122 will pass radially into lumen 93 as far as possible, limited by the size of opening 120 and partially occluding lumen 93.

The device operates in a similar manner when ramps 30 and 40 are not facing ball 122 or are partially facing ball 122. That is, needle 10 no longer constrains ball 122 as needle tip 25 passes ball 122. Spring 110 urges ball 122 along opening 120 such that ball 122 moves out of slot 75 and pivots about edge 155. Ball 122 is restricted from entering lumen 93 by the size and geometry of opening 120. Thus, ball 122 partially occludes lumen 93.

The position of ball 122 in opening 120 and partially occluding lumen 93 is shown in fig. 5& 7. When ball 122 moves to the point of partially occluding lumen 93, enlarged cross-sectional area 14 abuts rear opening 140 of cap 100 and further pulling of needle 10 will cause shield assembly 90 to move away from catheter hub 52 (since ball 122 is no longer in groove 75). The force exerted on ball 122 by groove 75 due to pulling the needle in a proximal direction may push ball 122 radially into lumen 93.

The interaction of enlarged cross-sectional area 14 on needle 10 and rear opening 140 of second housing 100 will prevent movement of the shield assembly in the distal direction (so that shield assembly 90 slides away from distal end 20 of the needle). Shield assembly is prevented from moving in a proximal direction (so as to expose needle tip 25) by abutment of distal end 20 of needle 10 against ball 122.

The distance from enlarged cross-sectional area 14 to tip 25 is such that when tip 25 is aligned with ball 122, there is sufficient space for the ball to move under second housing 100 in opening 120. The angle formed by upper surface 136 tangent to ball 122 is the same as described above with reference to fig. 3. Distal end 97 of first housing 95 and cap 100 are sized to extend outwardly such that tip 25 cannot be exposed from distal end 97 of shield 90. It is also possible to use a plurality of pellets placed in the same plurality of openings as openings 120 and 150. If so, the outward protrusion of distal end 97 and cap 100 may be reduced, thereby making shield assembly 90 more compact.

After deployment but before needle 10 is moved distally, a portion of ball 122 is in lumen 93 and a portion thereof is pushed against distal wall 157 of opening 120 by spring 110. The top of ball 122 is below distal end 135 of second housing 100. In an alternative embodiment, the expanded spring 110 closes off the top of the opening 120. Thus, ball 122 is radially and axially constrained within opening 120. When needle 10 is moved distally, it will abut ball 122 and ball 122 will press against distal wall 157 and surface 136 of second housing 100. This will prevent further distal movement of needle 10 and thus prevent needle tip 25 from being exposed from the shield assembly.

Lumen 93 is sized so that needle 10 fits relatively snugly inside it. Thus, when needle 10 is moved distally (i.e., shield 90 is moved proximally) and ball 122 abuts needle tip 25, needle 10 will not move off of ball 122. Lumen 93 thus provides support opposite ball 122 to prevent needle 10 from wobbling and to prevent tip 25 from moving to penetrate first housing 95. The snug fit between lumen 93 and needle 10 also facilitates threading of shield 90 over (threading) needle 10 (i.e., threading the distal end of shield 90 over the proximal end of the needle). A snug fit means that the shield is guided such that the proximal end 15 of the needle 10 enters the opening 140 in the proximal end 130 of the cap 100. This is important because opening 140 is typically only 0.001 inches larger than the diameter of needle 10.

In an alternative embodiment, ball 122 is fully within lumen 93. Ball 122 has a diameter slightly larger than the diameter of lumen 93. Ball 122 is then axially constrained by lumen 93 and needle 10. Lumen 93 is also sized to provide support for needle 10 opposite ball 122, thereby preventing needle wobble and preventing tip 25 from piercing first housing 95.

To exit slot 75, ball 122 is moved a distance at least equal to the amount it protrudes from opening 150 plus the wall thickness of cap 100 (about 0.003 "to 0.005"). When the shield is deployed, ball 122 extends into lumen 93 by an amount approximately equal to this distance. This causes a portion of lumen 93 to become occluded. When a smaller gauge needle is used, a larger ball is required to block lumen 93 sufficiently to prevent needle tip 25 from protruding through the unblocked portion of lumen 93. The ball can be smaller when a larger gauge needle is used (i.e., the ball can be smaller when the needle has a larger diameter).

The above description includes the operation of needle shield 90 with catheter assembly 50, providing a mechanism for locking and unlocking shield 90 on catheter assembly 50 in addition to the needle shielding function. This provides the additional advantage of ensuring that shield 90 cannot be removed from catheter hub 52 until needle tip 25 is shielded. When catheter locking is not required, cap 100 can be closed (i.e., without opening 120) and slightly enlarged to accommodate the entire diameter of ball 122.

A second type of catheter introducer assembly using the present invention is described below. In this second type of catheter introducer, the tube covers the entire length of the needle when it is shielded and limits further distal movement of the needle shield. Refer to fig. 9-14.

The body is penetrated by a needle 210, the needle 210 having an outer surface 212, a proximal end 215, a distal end 220, and a lumen 222. Distal end 220 has a sharp point 225. The distal end is beveled and has two beveled surfaces-surfaces 230 and 240 that form a ramp extending in a proximal direction from the sharp point 225. More or fewer than two ramps may also be used. Proximal end 215 is secured to needle hub 245.

Needle hub 245 has a rearwardly extending tube 250 from which it is secured to proximal end 215 of needle 210. Needle hub sleeve 250 has a proximal end 254 and a distal end 252 (to which distal end 252 needle 210 is secured). Needle hub cannula 250 has a lumen 260, which lumen 260 is coaxial with lumen 220 of needle 210 so that fluid can flow along lumen 222 into lumen 260. The needle hub sleeve 250 is integral and coaxial with another tube 255, the tube 255 forming a handle and having a proximal end 258 and a distal end 256. Tubes 250 and 255 are connected at the back 275 (proximal end) of the assembly. That is, proximal end 254 of needle cannula 250 and proximal end 258 of handle cannula 255 are joined at back 275. Needle hub 250 is open at the back (having hole 270) and needle hub 250 is fitted with a vent plug to allow air but not liquid to escape as fluid enters lumen 222 and flows into lumen 260. Both tubes 250 and 255 are transparent (or have at least a transparent portion) so that the fluid flow can be seen by the user. Tube 255 has a peripheral flange 272 at distal end 256, which peripheral flange 272 is approximately in line with the area where proximal end 215 of needle 210 is secured to needle hub 245. The tube 255 also has an inner peripheral flange 274, the inner peripheral flange 274 being substantially in line with the outer flange 272. The combination of the needle hub sleeve 250 and the handle tube 255 can be thought of as two concentric cylinders. Between tubes 250 and 255 is an annular space 276 extending from distal end 256 to a back 275.

Catheter assembly 280 has a catheter adapter or hub 282, the catheter adapter or hub 282 having a proximal end 285, a distal end 288, and a lumen 290 extending therebetween. The catheter 286 extends distally away from the distal end 288. The needle 210 is in the lumen 290 of the catheter assembly 280 prior to insertion into the body. Once needle 210 is inserted into the patient with catheter 286, needle 210 is removed by pulling needle 210 in a proximal direction. Catheter hub 282 has an inner surface 292 and an outer surface 291. The inner surface 292 is provided with a circumferential groove 293, the purpose of which groove 293 is as described above and will be described as appropriate. A single concave portion, indentation, circumferential ridge or convex portion will serve the same purpose as the circumferential groove.

Needle shield assembly 2110 has a proximal end 2120, a distal end 2115 and a lumen 2112 extending from the proximal end to the distal end. Lumen 2112 is sized to allow shield assembly 2110 to slide axially and rotate on needle 210 at distal end 2115. Shield assembly 2110 includes two parts-first housing 295 and cap 2100. Cap 2100 is at distal end 2115 and fits inside catheter hub 282. Shield 2110 is concentric with tubes 250 and 255. When the shield is in its non-deployed position, the first shell 295 of the shield 2110 is at least partially within the annular space 276. The first housing 295 is slidable back and forth in the axial direction in the annular space 276. The first housing 295 is also at least partially transparent to enable a user to see the fluid flow. Proximal end 2120 of shield 2110 is provided with circumferential flange 2117. When shield 2110 moves axially in a distal direction along annular space 276, flange 2117 will eventually abut inner flange 274 of handle tube 255 and will be prevented from further distal movement. In the deployed position, the proximal end 2121 abuts the inner flange 274 at the distal end 256 of the handle tube 255.

First housing 295 has a distal end 297 with a stepped area 2105 (an area of reduced diameter that enables coil spring 2111 to be disposed on first housing 295 and cap 2100 to be disposed thereon). Stepped region 2105 can be formed separately from first housing 295 and mounted thereon. The spring 2111 is a compression spring that exerts a force axially in the proximal and distal directions. Toward distal end 297 of first housing 295 (but still in stepped region 2105), first housing is provided with an opening 2120, which opening 2120 is sized to receive ball 2122.

Cap 2100 is a metal stamping having a proximal end 2130 and a distal end 2135. When first housing 295 and cap 2100 are assembled, second housing 2100 covers distal end 297 of the first housing and spring 2111. Cap 2100 is provided with an opening 2150 that is sized so that a portion of ball 2122 can protrude through it into groove 293. Cap 2100 is sized to fit within catheter hub 282. The portion of first housing 295 immediately adjacent stepped region 2104 also fits into catheter hub 282.

When needle shield assembly 2110 is mounted on catheter hub 282 (i.e., cap 2100 and a portion of first housing 295 are in catheter hub 282), a portion of ball 2122 projects through opening 2150 and is in groove 293 prior to deployment. This locks needle shield assembly 2110 to catheter hub 282 while allowing catheter hub 282 to rotate relative to needle shield assembly 2110 depending on the extent of groove 293 (i.e., whether the groove is circumferential or only limited movement is possible because it does not extend around the entire inner circumference of the catheter hub). A portion of ball 2122 is also in lumen 2112 of first shield assembly 2110 and abuts outer surface 212 of needle 210 (i.e., ball 2122 contacts outer wall 212 of needle 210). Needle 210 and shield assembly 2110 are able to slide and rotate relative to each other with very low friction. Ball 2122 is radially constrained by groove 293 and needle 210. Thus, needle shield assembly 2110 is locked in catheter hub 282. Spring 2111 exerts a force axially on ball 2122 in the distal direction. Also, needle 210 abutting ball 2122 will radially restrain ball 2122 and prevent it from exiting groove 293. This is also shown in fig. 11.

Once catheter tube 286 has been placed in the patient, needle 210 is pulled in a proximal direction (that is, needle shield assembly 2110 is moved towards tip 225 of needle 210 or needle hub 245 is pulled proximally). When bevels 230 and 240 are facing ball 2122 and then when first bevel 240 is aligned with ball 2122, ball 2122 is less radially constrained by needle 10 and is urged by spring 2111, which begins to move distally and radially into opening 2120. Ball 2122 thus exits opening 2150 in cap 2100 and groove 293 in catheter hub 282 and further radially inward into lumen 2112 of shield assembly 2110, pivots about edge 2155 (the wall of opening 2150 in cap 2100), and slides distally along the length of opening 2120. When second bevel 230 is aligned with ball 2122, needle 210 no longer constrains it radially and the ball moves completely out of groove 293. When ball 2122 is positioned such that edge 2155 is above it, ball 2122 will pass radially into lumen 1212 as far as possible, constrained by the size of opening 2120 and partially occluding lumen 2112.

When bevels 230 and 240 do not face ball 2122 or partially face ball 2122, the device operates in a similar manner as described above. Spring 2111 urges ball 2122 along opening 2120 so that ball 2122 exits groove 293 and pivots about edge 2155. Ball 2122 is restricted from entering lumen 293 by the size and geometry of opening 2120. Thus, ball 2122 partially occludes lumen 2112.

After ball 2122 has moved to the point where it partially occludes lumen 2112 (as described above), flange 2117 of shield assembly 2110 abuts interior flange 274 of tube 255 and further pulling of needle 210 causes shield assembly 2110 to move away from catheter hub 282 because ball 2122 is no longer in groove 293. The force exerted on ball 2122 by groove 293 due to pulling the needle in the proximal direction also pushes ball 2122 radially inward into lumen 2112.

Shield assembly is prevented from moving in the distal direction (and thus shield assembly 2110 eventually sliding out of distal end 220 of the needle) by the interaction of flanges 274 and 2117. Movement of the shield assembly in the proximal direction (so as to expose needle tip 225) is prevented by distal end 220 of needle 210 abutting ball 2122 (which ball 2122 abuts wall 2157 of first housing 295 and upper inner wall 2136 of the second housing or cap 2100).

The distance from flange 2117 to needle tip 225 is such that when tip 225 is aligned with ball 2122, there is sufficient space for the ball to move under cap 2100 in opening 2120. It is contemplated that angles α and β (i.e., the tangent angle and the minimum bevel angle formed between ball 2122 and surface 2136) may be set as described above with respect to fig. 3.

After deployment but before needle 210 is moved distally, a portion of ball 2122 is in lumen 2112 and a portion thereof is urged against distal wall 2157 of opening 2120 by spring 2111. The top of ball 2122 lies below an upper surface 2136 of distal end 2135 of cap 2100. Distal end 299 of first housing 295 and the cap are also sized to extend outwardly such that tip 225 cannot be exposed from distal end 2115. Multiple pellets may also be used. The foregoing design also provides the foregoing catheter locking feature.

Once the shield is deployed (but before needle 210 is moved distally), a portion of ball 2122 is in lumen 2112 and a portion of it is urged against wall 2157 of opening 2120 by spring 2111. The top of ball 2122 lies below an upper surface 2136 of distal end 2135 of cap 2100. The opening 2120 may be closed by a spring 2111. Ball 2122 is radially and axially constrained within opening 212. When needle 210 is moved distally, it will abut ball 2122, which ball 2122 will press against distal wall 2157 of first housing 295 and wall 2136 of cap 2100. Thus, needle 210 cannot be distally exposed from the shield.

Lumen 2112 provides anti-oscillation support for needle 210 as described above with respect to the previous embodiments. The ball motion and ball size associated with the needle gauge size is also the same as described above. That is, larger pellets are used for smaller gauge sizes and vice versa.

First housing 295 and the tube portion of shield 2110 can be made from an extruded polymer tube 950, as shown in fig. 14 (see also fig. 20-22). The polymer tube 950 is relatively thin and flexible. This (and its extrusion) makes it very light and simple to manufacture, and the amount of material required to manufacture it is reduced compared to harder moulded parts. To provide stiffness and strength, the polymeric tube may be reinforced with co-extruded wires 956. Wire 956 is shown as a longitudinal wire extending along the length of tube 955. The longitudinal wires may alternatively be a co-extruded braid, mesh, grid or helix.

The catheter introducer assembly of the invention will now be described in which distal movement of the needle shield is limited by a tether secured to the needle hub. Refer to fig. 15-19. Needle hub 45 has a rearwardly extending tube 50 from which it is secured to proximal end 15 of needle 10. Needle hub sleeve 50 has a proximal end 54 and a distal end 52 (to which distal end 52 needle 10 is secured). Needle hub cannula 50 has a lumen 60, which lumen 60 is coaxial with lumen 22 of needle 10 so that fluid can flow along lumen 22 into lumen 60. Needle hub sleeve 50 forms a handle by which a user can grasp catheter assembly 5 to insert needle 10 into a patient.

Needle hub 50 is open at the back (having an aperture 70) and is fitted with a vent plug to allow air but not liquid to escape as fluid enters lumen 22 and flows into lumen 60. The tube 50 is transparent (or at least has a transparent portion) so that the fluid flow can be seen by the user. Tube 50 has a peripheral flange 72 at distal end 52, which peripheral flange 72 is approximately in line with the area where proximal end 15 of needle 10 is secured to needle hub 45.

The circumferential flange 72 is provided with a small opening 74, through which small opening 74 the tether 73 passes. Tether 73 has a proximal end 77 and a distal end 76. The proximal end is T-shaped. The T-shaped arm 79 prevents the tether 73 from escaping through the opening 74 when moving distally. Distal end 76 is secured to a needle shield assembly 110 (described below). In this manner, tether 73 prevents the needle shield assembly from moving in a distal direction away from tip 25 of needle 10. The tether 73 may be made of nylon and is very similar to a label holder (which is used in the retail industry to secure labels to clothing). The tether 73 may be integrally molded with the first housing 95, but need not be.

Catheter assembly 80 has a catheter hub 82, catheter hub 82 having a proximal end 85, a distal end 88, and a lumen 90 extending therebetween. Catheter 86 extends distally away from distal end 88. Needle 10 is in lumen 90 of catheter assembly 80 prior to insertion into the body. Once needle 10 is inserted into the patient with catheter tube 86, needle 210 is removed by pulling needle 210 in a proximal direction. Catheter hub 82 has an inner surface 92 and an outer surface 91. The inner surface 92 is provided with a circumferential groove 93, the purpose of which groove 93 will be appropriately described. A single concave portion, indentation, circumferential ridge or convex portion will serve the same purpose as the circumferential groove.

Needle shield assembly 110 has a proximal end 118, a distal end 115, and a lumen 112 extending from the proximal end to the distal end. Lumen 112 is sized to allow shield assembly 110 to slide axially and rotate on needle 10. Shield assembly 110 is contained within the mating components-first housing 95 and cap 100. Cap 100 is at distal end 115 and fits inside catheter assembly 80.

The first housing 95 has a distal end 97 with a stepped area 105 (an area of reduced diameter that enables a coil spring 111 to be disposed on the first housing 95 with the cap 100 to be disposed thereon). The spring 111 is a compression spring that exerts a force axially in the proximal and distal directions. Toward distal end 97 of first housing 95 (but still in stepped region 105), first housing is provided with an opening 120, opening 120 being sized to receive ball 122.

Cap 100 is a metal stamping having a proximal end 130 and a distal end 135. Cap 100 covers distal end 97 of the first housing and spring 111. Cap 100 is provided with an opening 150, the opening 150 being sized such that a portion of ball 122 can protrude through it into slot 93. Cap 100 is sized to fit within catheter hub 82. The portion of first housing 95 immediately adjacent stepped region 104 also fits into catheter hub 82.

When needle shield assembly 110 is mounted on catheter hub 82 (i.e., cap 100 and a portion of first housing 95 are in catheter hub 82), a portion of ball 122 protrudes through opening 150 and is in groove 93 prior to deployment. This locks needle shield assembly 110 to catheter hub 82 while allowing catheter hub 82 to rotate relative to needle shield assembly 110 depending on the extent of groove 93 (i.e., whether the groove is circumferential or only limited movement is possible because it does not extend around the entire inner circumference of the catheter hub). A portion of ball 122 is also in lumen 112 of first shield assembly 110 and abuts outer surface 12 of needle 10 (i.e., ball 122 contacts outer wall 12 of needle 10). Needle 10 and shield assembly 110 are able to slide and rotate relative to each other with very low friction. Ball 122 is radially constrained by groove 93 and needle 10. Spring 111 exerts a force axially on ball 122 in the distal direction. Moreover, needle 10 abutting ball 122 will radially restrain ball 122 and prevent it from exiting groove 93.

Once catheter tube 86 is placed in the patient, needle 10 is pulled in a proximal direction (i.e., needle shield assembly 110 is moved toward tip 25 of needle 10, or needle hub 45 is pulled proximally). When first bevel 40 and second bevel 30 are facing ball 122, then when first bevel 40 is aligned with ball 122, ball 122 is less radially constrained by needle 10 and is urged by spring 111, which begins to move distally and radially into opening 120. Ball 122 thus exits opening 150 in cap 100 and slot 93 in catheter hub 82 and further radially inward into lumen 112 of shield assembly 110, pivots about edge 155 (the distal wall of opening 150 in cap 100), and slides distally along the length of opening 120. When second bevel 30 is aligned with ball 122, needle 10 no longer constrains it radially and the ball moves completely out of groove 93. When ball 122 is positioned such that edge 155 is above it, ball 122 will radially enter lumen 112 as far as possible, limited by the size of opening 120 and partially occlude lumen 112. This is shown in fig. 6. The above operation is similar when ramps 30 and 40 are not facing ball 122, as described above in the other embodiment.

As needle hub 45 moves proximally, tether 73 is paid out through opening 74 so that arm 79 moves distally. When ball 122 moves to a point where it partially occludes lumen 112 (as described above), arm 79 of tether 73 abuts flange 72 and further pulling of needle 10 will cause shield assembly 110 to move away from catheter hub 82 because ball 122 is no longer in groove 93. The force exerted on ball 122 by groove 93 due to pulling the needle in a proximal direction may also push ball 122 radially into lumen 112.

Movement of the shield assembly in the distal direction is prevented by the interaction of arms 79 and flange 72 (so that shield assembly 110 will eventually slide off the distal end of the needle). Shield assembly is prevented from moving in a proximal direction (to expose needle tip 25) by distal end 20 of needle 10 abutting ball 122 (ball 122 abutting wall 157 of opening 120).

The distance from tether arm 79 to needle tip 25 is such that when tip 25 is aligned with ball 122, there is sufficient space for the ball to move under cap 100 in opening 120. The relationship between angle α (the tangent angle formed between ball 122 and upper surface 136 of distal end 135 of cap 100) and β (the minimum needle bevel angle) is as described above, also considering the support provided by lumen 112 opposite ball 122 to prevent needle 10 from wobbling and to prevent tip 25 from moving to penetrate first housing 95. The relationship between the size of the ball and the gauge of the needle is also described above.

As shown in fig. 20, needle hub 45 in the embodiment of fig. 15-19 may be constructed of a hard plastic component 940, with needle hub 45 having barbs 945 at its proximal end 947. Barb 945 mates with extruded polymer tube 950, as shown in fig. 22. The polymeric tube 950 is coextruded with a base tube 960, the base tube 960 forming a conduit along which the tether 73 extends. The polymer tubes 950 and 960 are relatively thin and flexible. This, together with their being extruded, makes the device extremely light and simple to manufacture, and the amount of material required to manufacture it is reduced compared to hard moulded parts. To provide stiffness and strength, the polymeric tube may be reinforced by co-extruded wires, braids, meshes, wire grids or spirals. This is shown in fig. 14.

The following describes the use of a needle shield for a hypodermic syringe (a needle-based device with no catheter threaded thereon). Refer to fig. 23-26. Syringe and needle assembly 5 is comprised of a syringe body 502, with syringe body 502 having a male luer adapter 506, and a female needle adapter 508 mated with male luer adapter 506. Needle adapter 508 has a hub 512, and proximal end 505 of needle 510 is bonded into hub 512. Needle 510 has a sharpened distal end 525.

Needle shield assembly 900 is comprised of two mating components-a first housing 905 and a second housing or cap 910. First housing 905 has a proximal end 909 and a distal end 907. Extending between the proximal and distal ends is a lumen 913, the lumen 913 having a diameter such that the first housing 905 can slide axially on the needle 10. Stepped region 915 extends from proximal end 909 toward distal end 907. This is a reduced diameter region that enables the coil spring 911 to be disposed on the first housing 905. Spring 911 is a compression spring that applies an axial force in the proximal and distal directions. At a distal end 907 towards first housing 905 (but still in stepped region 915), first housing is provided with an opening 920, opening 920 being sized to receive ball 922.

The second housing or cap 910 has a proximal end 930 and a distal end 935. The proximal end 930 is provided with an opening 937, the opening 937 being sized such that it is slightly larger than the diameter of the needle 510. In this manner, second housing 910 can slide axially along the needle from proximal end 505 toward distal end 525. When first and second housings 905 and 910 are assembled, second housing 910 covers most of first housing 905 except for the proximal end. Thus, the second housing covers the spring 911. Second housing 910 is provided with an opening 940, which opening 940 is sized such that a portion of ball 922 can protrude through it. This makes needle shield assembly 900 very compact. However, second housing 910 may be made slightly larger or provided with a blister to accommodate ball 922 so that ball 922 is completely covered.

When needle shield assembly is on needle hub 512, a portion of ball 922 protrudes through opening 940 prior to deployment. A portion of ball 922 is also in lumen 913 of first housing 905 and abuts outer surface 522 of needle 510 (i.e., ball 922 contacts outer wall 522 of needle 510). Shield assembly 900 can be slid from this position in the distal direction along needle 510 with very low friction. Ball 922 is radially constrained by the diameter of opening 940, which opening 940 is sized such that ball 922 cannot escape and exit shield 900 through opening 940. Ball 922 is also radially constrained by needle 510 in other directions. Spring 911 exerts an axial force on ball 922 in the distal direction.

Tether or strap 800 is mounted on proximal end 909 of first housing 905. It is preferably, but not necessarily, manufactured in the same molding as first housing 905. Tether 800 has a distal end 802 (mounted to proximal end 909 of first housing 905) and a proximal end 804 (proximal end 804 extending rearwardly and outwardly from shield 900). At the proximal end 804, there is a handle 806, the handle 806 being capable of being grasped by a user. This is molded with the strap 800, but may be a separate component mounted on the strap 800. Tether or strap 800 is made of a flexible, semi-rigid material such as nylon. Any material that is capable of bending but provides some longitudinal compressive strength is suitable as long as it enables a force to be applied to the shield 900 through the tether 800.

Needle hub 512 is integrally molded with limiter 514. Limiter 514 has a track 516 along which tether 800 can slide in a distal direction as needle shield 900 slides distally along needle 510. The limiter 514 has a stop 518, and when the handle 806 reaches the stop 518, the stop 518 prevents further travel of the tether 800. The limiter 514 has an open channel 520, the open channel 520 enabling the tether 800 to be placed in the track 516 during manufacturing, but the open channel 520 prevents the tether 800 from being easily removed.

Once needle 510 has been used and is to be shielded, the user simply grasps handle 806 and pushes it so that needle shield 900 slides distally along needle 510. When needle shield 900 reaches a point where needle tip 525 passes ball 922, ball 922 is less radially constrained by needle 510 and, urged by spring 911, it begins to move distally and radially into opening 920. As such, ball 922 exits opening 940 and further radially inward into lumen 913 of shield assembly 900, pivoting about edge 955 (which edge 955 is a wall of opening 940 in second housing 910). When needle tip 525 passes ball 922, needle 510 no longer constrains ball 922. Spring 911 urges ball 922 along opening 920 such that ball 922 pivots about edge 955. Ball 922 is constrained from entering lumen 913 of first housing 905 by the size and geometry of opening 920. Ball 922 thus partially occludes lumen 913.

When ball 922 moves to a point where it partially occludes lumen 913, handle 806 contacts stop 518, thereby preventing further pushing of handle 806 and thus tether 800. Shield assembly 900 is prevented from moving in the distal direction by abutment of stop 518 and handle 806 (so that shield assembly 900 will slide away from distal end 525 of the needle). Shield assembly is prevented from moving in a proximal direction (to expose needle tip 525) by distal end 525 of needle 510 abutting ball 922.

Tether 800 (to tip 525) has a length, as compared to the length of first housing 905, such that when tip 525 is aligned with ball 922 there is sufficient space for the ball to enter lumen 913 at least partially. The same considerations as described above for the catheter introducer apply when selecting the angle between ball 922 and the portion of needle shield 900 that is just radially outward of ball 922 and against which ball 922 abuts when the shield is deployed. Proximal end 909 of first housing 905 is sized to extend outwardly such that tip 525 cannot be exposed from distal side 907.

When shield 900 is deployed, a portion of ball 922 is in lumen 913 and a portion thereof is below distal end 935 of second housing 910, which second housing 910 radially constrains it. As shield assembly 900 moves proximally, ball 922 will abut needle tip 525 and press against the distal and upper interior walls of second housing 910. This will prevent further proximal movement of the shield assembly and thus exposure of the needle tip 25.

Lumen 913 is sized such that needle 510 fits relatively snugly into lumen 913. Thus, when needle shield 900 is moved proximally into the deployed position with ball 922 abutting needle tip 525, needle 510 will not move off of ball 922. Lumen 913 thus provides support opposite ball 922 to prevent needle 510 from wobbling and to prevent tip 525 from moving such that it pierces first housing 905.

In an alternative embodiment, ball 922 enters lumen 913 entirely. Ball 922 has a diameter slightly larger than lumen 913. Lumen 913 is also sized to provide support for needle 910 opposite ball 922, thereby preventing wobbling of the needle and preventing tip 525 from penetrating first housing 905.

Fig. 27 and 28 illustrate the use of the present invention with a winged needle. In this embodiment, shield assembly 6110 (of the type described with reference to fig. 9-13) is mounted on sheath 600. Sheath 600 has a slot 603 that allows the sheath to slide over wings 602 and tube 606. The back 604 of slot 603 abutting wings 602 will prevent distal movement of shield assembly 6110.

Figures 29 and 30 show another winged needle application. In this use, a needle assembly 7110 (which is also of the type described with reference to fig. 9-13) is provided with a wing 702. Needle hub 45 is squeezed between the fingers to release it from body tube 704. A flange on tube 700 abuts against the collar at 706 to prevent further proximal movement of needle hub 45, at which point the needle shield assembly is deployed, preventing distal movement of tip 25.

Another winged needle (with or without a catheter) of the present invention is shown in Figs. 31 and 32. In this embodiment, needle hub 845 is mounted to first and second wings 802 and 804. Wings 802 and 804 are disposed around tube 806. Wings 802 and 804 each have protrusions 812, 814 and 808, 810, respectively, that act as hinges to allow some rotation of wings 802 and 804 about tube 806. Boss 808 is mounted or abutted against needle assembly 8110 at proximal end 8120 and is provided with a relatively short lumen so that boss 808 can slide axially along needle 10 and thus wing 804 can slide axially along needle 10. The projection 810 also has a lumen that enables it to slide axially along the tube 806. Movement of wing 804 is limited between protrusions 812 and 814 of wing 802.

When the ball is moved to its shielding position (as described above), thereby preventing proximal movement of shield assembly 8110, projection 810 of wing 804 abuts projection 812 of wing 802, thereby preventing distal movement of wing 804, and therefore shield assembly 8110.

The Huber needle of the present invention is shown in fig. 33 and 34. In this embodiment, needle hub 1045 has a general L-shape and tether 1075 is generally parallel to needle 1010 except that it is slightly arcuate due to gravity. Wing 1004 has an opening 1002 in which opening 1002 needle shield assembly 10110 (of the type described with reference to fig. 16-19) is located prior to deployment, locked in place by ball 10122. Ball 10122 allows the shield assembly to be removed from opening 1002 while needle tip 1025 is shielding. At this point, tether 1075 is fully paid out and shield assembly 10110 is prevented from moving distally.

Fig. 35 illustrates a blood collection set including the shield shown in fig. 23-26. Figures 36-48 illustrate some alternative embodiments. Figure 36 shows spring 111 on one side of needle 10, parallel to the needle axis, rather than around needle 10. In fig. 37, spring 111 is a torsion spring that provides a torsional force about the axis of needle 10. This exerts a circumferential force on ball 122. Opening 120 is configured to allow circumferential movement of ball 122 toward lumen 93. Fig. 38 shows that the spring 111 is disposed outside the first housing 95. Fig. 39 shows piston 101 disposed between spring 111 and ball 122. In fig. 40, the piston 101 is in the form of a cap interposed between the spring 111 and the ball 122. In this embodiment, the spring 111 is not enclosed by the cap 100.

Fig. 41 shows a spring 111 in the form of a reed, the spring 111 being integral with the cap 100. The spring 111 may be a separate component from the cap 100 or may be formed with the cap 100. Fig. 42 shows spring 111 in the form of a thin corrugated washer which fits over needle 10.

While a spherical shape is the preferred choice for ball 122, a preferred spherical object is not necessary. In the embodiment of fig. 43, roller 102 replaces ball 122.

In fig. 44, groove 75 is lined with metal to provide a higher pull-out force and to reduce undercuts in catheter 52, making it easier to mold catheter hub 52. In this embodiment, metal bushing 750 is an extension of metal wedge 751, which secures catheter tube 86 to the catheter hub. The metal bushing 750 may of course be a separate ring or a partial ring.

Ball 122 may be enclosed in cap 100 as shown in fig. 45-47. Ball 122 does not provide a lock with the catheter hub at this time. In the embodiment shown in fig. 47, cap 100 is enclosed by a flexible metal or plastic skin 105, which skin 105 covers opening 150 and allows movement of ball 122 so that it can be unlocked from catheter hub 52. This structure can be replaced by a protrusion or circumferential projection, neck or channel formed of hard metal.

In the embodiment of fig. 48, ball 122 rests on piston 800, which piston 800 abuts needle 10 in the non-deployed position. When the shield is deployed, piston 800 moves with ball 122. The size of the piston 800 varies according to the gauge of the needle. Thus, this embodiment enables one size of pellet to be used with a variety of needle sizes.

In the embodiment of fig. 49-51, the shield assembly described above is used in a Y-catheter introducer assembly, where needle 10 is pulled through septum 6000.

While needle shield assemblies, their components, and their use with various needle devices have been described and illustrated, such description is not intended to limit the scope of the basic invention. Many variations and modifications will be apparent to those of ordinary skill in the art. Accordingly, needle shield assemblies and their components constructed in accordance with the principles of the present invention may be practiced otherwise than as specifically described herein. The invention is also defined in the appended claims.

Claims (11)

1. A method of manufacturing a needle assembly comprising the steps of:

providing a needle having a proximal end, a sharp distal end, and a longitudinal axis;

providing a needle shield assembly comprising: an occlusion carrier, an occlusion, and a lumen coaxial with the longitudinal axis of the needle, the lumen having a proximal end and a distal end, wherein the occlusion is movable from a shielding position in which the occlusion at least partially occludes the lumen to a non-shielding position in which the needle is slidable along the lumen;

placing the obstruction in the obstruction carrier and in a shielding position;

inserting the proximal end of the needle into the distal end of the lumen; and

the needle shield assembly is moved such that the needle moves the blocking object from the shielding position to the non-shielding position.

2. The method of claim 1, further comprising the steps of: the step of mounting a spring on the blocking object carrier such that the spring biases the blocking object towards the longitudinal axis of the needle.

3. The method of claim 1, further comprising the steps of: the catheter is threaded over the needle.

4. The method of claim 1, further comprising the steps of: the catheter adapter is snapped onto the needle shield assembly.

5. The method of claim 1, wherein: the obstruction is a pellet.

6. The method of claim 1, wherein: the obstruction is a roller.

7. The method of claim 1, wherein: in the shielding position, the blocking object carrier holds the blocking object at a position offset from the longitudinal axis of the needle.

8. The method of claim 2, wherein: the step of mounting the spring on the stopper carrier includes the step of threading the spring on the stopper carrier.

9. The method of claim 3, further comprising the steps of: with at least a portion of the needle shield assembly disposed within the catheter adapter.

10. The method of claim 3, further comprising the steps of: the catheter adapter is placed over the needle shield assembly and the needle shield assembly is locked to the catheter adapter such that in the shielding position the blocking object releases the needle shield assembly from the catheter adapter and in the non-shielding position the blocking object locks the catheter adapter to the needle shield assembly.

11. The method of claim 3, further comprising the steps of: the catheter adapter is placed over the needle shield assembly in the shielding position and the needle shield assembly is brought into the non-shielding position, thereby locking the catheter adapter to the needle shield assembly.