SAFETY CATHETER ASSEMBLY

A safety catheter assembly has a clip guard that covers and protects the needle clip from the time that the catheter assembly is shipped out in the ready state, through its use where the distal tip of the needle is entrapped in the needle clip after use, and to when the clip guard and the safety needle clip housed therein are removed from the catheter hub. A passive safety system of the needle clip couples the catheter hub and the needle housing in the ready state and during the use of the catheter assembly, and releases the catheter hub from the needle housing once the contaminated needle tip is captured in the needle clip. A wiper provided to the catheter assembly wipes blood from the needle to prevent exposure of the contaminated blood. The wiper may also act to retain a septum in the catheter hub. The clip guard may be adapted to be used with a catheter hub having a multiuse seal member.

FIELD OF THE INVENTION

The present invention relates to safety catheter devices that may include a closed system catheter (CSC) assembly having a needle tip protection guard housing a passive release mechanism that shields the sharp distal tip of the needle of the device from when the device is ready to be used to the disposal of the device after use, and a mechanism adapted to remove blood that may have adhered to the needle during use.

BACKGROUND OF THE INVENTION

A conventional catheter assembly typically has a catheter hub and a catheter tube extending distally thereof, and a needle assembly mounted together in an over-the-needle fashion. The needle assembly typically includes a needle hub or support and a needle cannula extending distally from the needle hub. A closed system catheter (CSC) is a catheter assembly that has a sideport at the catheter hub where a tubing from the sideport may be coupled to a fluid store device such as a syringe or a fluid pump. The sideport for a CSC assembly is an external port conventionally angled backward toward the proximal end of the catheter, with the tubing extending from the non-catheter hub end of the external port. In a ready to use position, a needle cannula attached to a needle hub of the needle assembly extends through the catheter tube to expose its sharp distal tip distally beyond the distal end of the catheter tube. The sharp distal tip of the needle cannula is used to penetrate the tissue of the patient for insertion of the catheter tube within the vasculature system of a patient. Once the catheter tube is disposed correctly within the vasculature, the needle cannula is withdrawn from the catheter assembly so that a fluid path is established between the fluid store and the vein or artery of the patient, via the sideport and the interior cavity of the catheter hub. A needle tip protector may be provided in the catheter assembly to capture at least the sharp distal tip of the needle cannula, if not the entire cannula, after use.

The catheter hub typically has an open proximal end adapted to receive a male luer taper into the interior cavity of the catheter hub to establish a fluid connection between the patient's vasculature and the luer taper. The proximal end may also be provided with external ears, flange or the like to secure the luer taper in the catheter hub, for example when the luer taper is coupled with a male luer lock collar or nut to form part of a male luer lock connector of an administration set or the end of a syringe, or the like. Under normal conditions, after withdrawal of the needle cannula and before a luer taper is inserted into the catheter hub, blood immediately starts flowing through the catheter tube and into the interior cavity of the catheter hub. For a CSC assembly, a septum may br provided in the catheter hub to prevent the blood from back flowing to the proximal luer end of the catheter hub.

Fluid such as for example contaminated blood that may have adhered to the distal portion of the needle conceivably may be exposed to the environment. In use, the distal tip of the needle cannula, which extends beyond the distal end of the catheter, is inserted into the vein or artery of the patient. Once the catheter is correctly placed, the needle cannula is removed. The distal tip of the needle, insofar as it was inserted into for example the vein of the patient, is exposed to the blood of the patient. Blood therefore will most likely adhere to the distal portion of the needle. There is always the chance that the contaminated blood adhered to the needle would be exposed to the environment.

SUMMARY OF THE PRESENT INVENTION

The present invention safety catheter assembly provides an improvement over the prior art safety catheter assemblies by having a needle tip protector, or needle clip, housed in a needle tip protector guard, or clip guard, that covers the proximal portion of the catheter hub from the ready state to when the needle has been withdrawn from the patient and entrapped in the needle clip. A wiper mechanism, or simply wiper, is preferably provided at the proximal end of the catheter hub to wipe off blood that may have adhered to the needle due to the distal portion of the needle having inserted into the patient. The wiper mechanism acts to remove blood from the needle as the needle is withdrawn from the catheter hub into the needle tip protector. A wiper mechanism fitted to the opened proximal end of the catheter hub also acts to close off the proximal end of the catheter hub in addition to wiping off the blood that has adhered to the needle. All the while, the needle clip remains covered by the clip guard so that neither the tip of the needle nor the needle clip is exposed to the environment. The wiper mechanism may also be used to retain a seal member or septum provided in the internal cavity of the catheter hub. The needle clip is a passive mechanism that couples the catheter hub and the clip guard together and traps the distal tip after use. The needle clip has fingers or catches that grasp or grip at least one portion of at least one outwardly extending flange at the proximal end of the catheter hub before the distal tip is fully entrapped within the needle clip. Once the distal tip of the needle is trapped in the needle clip, the fingers of the needle clip would release its grip of the flange of the catheter hub to disengage the clip guard from the catheter hub.

The present invention is directed to a catheter assembly comprising: a catheter hub having a body defined by a wall having a distal end and an opened proximal end having a flange, and an internal cavity defined by an inner surface of the wall between the distal end and the opened proximal end; a catheter having a distal end extending from the distal end of the catheter hub along a longitudinal axis; a wiper member including a distal section having a cross dimension configured to fit into the opened proximal end of the catheter hub distal of a proximal end of the seal member and a proximal section having a cross dimension larger than the cross dimension of the distal section; a needle housing having a guard having an open distal end and a needle hub; a needle having a proximal end attached to the needle hub and a sharp distal tip extending away from the open distal end of the housing along the longitudinal axis, the needle slidably extending along the catheter so that its distal tip extends past the distal end of the catheter when the catheter assembly is in a ready to use position; a needle tip protector slidably positioned along the needle; wherein the opened distal end of the guard opens to a chamber configured to house the needle tip protector.

The present invention is further directed to a wiper mechanism provided between the catheter hub and the clip guard to wipe off excess blood adhered to the needle as the needle is being removed form the catheter hub to prevent accidental exposure of contaminated blood to the environment and potential harm to the user or clinician. The wiper mechanism may be provided to the proximal end of the catheter hub and is configured to operate with the needle clip.

The invention furthermore is directed to the needle clip being non-removably housed in the clip guard, which is configured to cover the proximal portion of the catheter hub to ensure that the distal portion of the needle is enclosed throughout the life and use of the catheter assembly.

DETAILED DESCRIPTION OF THE INVENTION

For the discussion below, it should be appreciated that the term “distal”, as used herein, refers to the direction along an axis that lies parallel to a needle cannula of a safety catheter assembly, that is closest to the subject during catheter insertion. Conversely, the term “proximal,” as used herein, refers to the direction lying along the axis parallel to the needle cannula that is further away from the subject when the catheter is inserted into the vein of the subject, opposite to the distal direction. Other terms that may also be used to refer to the distal end and proximal end of the safety catheter device may include “patient end” and “user end”, respectively. Also, for the sake of simplicity, the catheter assembly device, or peripheral intravascular catheter (PIVC) assembly, and the closed system catheter (CSC) assembly may be referred to as “catheter assembly” or “safety catheter”, the needle tip protector as “safety needle clip” or simply “safety clip” or “needle clip”, the wiper member or mechanism as “nose wiper” or simply “wiper”, and the needle guard assembly that overlies the proximal portion of the catheter hub and houses the needle clip to isolate the needle clip from the environment simply as “clip guard”.

The following US applications and patents, assigned to the same assignee as the present application, relate to safety catheters/catheter assemblies: application Ser. Nos. 15/733,439, 15/435,700, U.S. Pat. Nos. 8,652,104, 10,080,867, 10,548,522 and 10,675,440. The respective disclosures of the '439 and '700 applications and the '104, '867, '522 and '440 patents are incorporated by reference to the disclosure of the present application.

With reference toFIGS.1,2and4a-4c, an exemplar sideport safety catheter assembly, or catheter assembly2as discussed herein, is shown to have a catheter hub4, a needle housing6and a sheath8that covers a catheter10that extends distally from catheter hub4. A needle12has a sharp distal tip12athat extends beyond the distal end10aof catheter10. A non-patient end12bof needle12is fixedly attached to a needle hub6cof needle housing6. The needle shaft defines a lumen and may have a side orifice proximate to its distal tip as is conventionally know to enable fluid to flow into the lumen and egress at the orifice into a space defined between the outer wall of the needle and the inner wall of the catheter and may flow into a flash chamber when the distal end of the needle is inserted into a patient. Needle housing6has an opened distal end adapted to receive a needle tip protector guard, or clip guard14hereinafter. As shown inFIGS.1,2and4c, catheter hub4has a pair of wings4afor securing the catheter hub to the skin of the patient as is conventionally known. A sideport hub, or simply sideport16, integrally extends transversely from catheter hub4. Sideport16is shown being covered by a snap on cap18. A flash plug21is attached to the proximal end6aof needle housing6to enable a user or clinician to monitor blood at the flash chamber of needle housing6to determine whether the needle, and the catheter that fits over the needle, are correctly placed into the vasculature of the patient as conventionally known.

FIG.3is an enlarged cross-sectional view of the catheter hub. As shown, catheter hub4has a distal end4band a proximal end4c. One continuous flange4dor multiple protuberances or flanges4dintegrally extend transversely from proximal end4c. Catheter hub4is shown to have a body defined by a wall4ethat forms an internal cavity4f. Integrally extending outwardly from the main body of catheter hub4is a sideport hub16, which has a passage or bore16athat extends into internal cavity4fvia an opening16bat wall4eto establish a fluid communication path between the internal cavity of the catheter hub4and sideport16. A cylindrical seal member20which may be made from a flexible resealable elastomeric material such as silicone or polyisoprene is fitted in the portion of internal cavity4fto block opening16b. As is conventionally known, with cap18removed, the open end16cof sideport hub16may be connected to a fluid store such as a syringe or a fluid injection pump, possibly by means of a tubing, so that fluid under pressure may be injected into sideport16. Seal member20is responsive to a given pressure so that when the fluid injected into sideport16exceeds the given pressure, seal member20opens to establish a through fluid path between fluid store and internal cavity4fof catheter hub4, and from there through catheter10to the vein of the patient.

With reference toFIGS.4a-4c, the sideport catheter assembly is shown to have a proximal portion of its catheter hub4covered by its needle tip protector guard, or simply clip guard14. A substantial portion of clip guard14is shown to be received in distal portion6bof needle housing6. The sideport catheter assembly shown inFIGS.4a-4cis in a ready to use position, a ready to use state or simply a ready state.

As shown inFIGS.9and10a-10b, clip guard14has an opened distal end14athat opens into a chamber14bdefined by a body14chaving a top wall or surface14c1, a bottom wall14c2, and two side walls14c3and14c4that taper from the a flat surface proximal from distal end14ato a base14dthat includes a hollow shaft14e. An upright14frises from top surface14c1to assist the user or clinician to direct the movement of the needle into the patient. It should be appreciated that the embodiment of the catheter assembly shown inFIGS.10a-10bis not the sideport catheter assembly shown inFIGS.1-3.

A needle tip protector, or needle clip22, is non-removably housed in chamber14bof clip guard14. An exemplar embodiment of needle clip22is shown inFIGS.13a-13b. As shown in the ready state of the catheter assembly, needle clip22is slidable along needle12, which lies along the longitudinal axis of the catheter assembly. Needle clip22may be made from a metallic material such as stainless steel but with a thickness sufficient to enable the needle clip to be relatively rigid but yet flexible for those parts that require flexibility or bendability when biased. In particular, needle clip has a base22athat has an opening22b. Opening22bis configured to have a dimension that enables needle clip22to slide freely therealong but prevent a needle feature12c(FIG.6) such as a protuberance or an enlarged portion of the needle proximate to distal tip12ato pass through. This is so that when needle feature12cmakes contact with opening22b, further proximal movement of needle12relative to catheter hub4would cause needle clip22to move in unison with needle12in the proximal direction.

With reference toFIGS.5-6and13a-13bwhich do not show the clip guard, needle clip22is shown to have two arms22c1and22c2that extend substantially transversely in the distal direction from opposite ends of base22a. Respective mid-sections22d1and22d2of the arms22c1and22c2are bent inwardly toward the center of needle clip22, with the tip ends of those mid-sections curved to form corresponding catches or barriers. The mid-sections henceforth are referred to as barriers22d1and22d2. As per shown inFIG.6, needle feature12cis in stop contact with opening22bat the base of needle clip22. Thus, distal tip12aof needle12is entrapped in needle clip22, with barriers22d1and22d2returning to their natural positions since they are no longer biased by needle12. As shown, barrier22d1is distal to barrier22d2, with distal tip12aof needle12proximal to both barriers22d1and22d2.FIG.6shows the catheter assembly in the safe state as the contaminated distal tip of the needle is trapped inside needle clip22.

Further with reference toFIGS.5-6and13a-13b, the respective portions of arms22c1and22c2are configured to have slots defined by parallel rails. In particular, parallel rails22e1and22e2extend from the mid-section of arm22c1to a cross end22e3that connects the rails to define a slot22e4with a width that allows needle12to pass through. As shown, rails22e1and22e2extend distally coplanarly with arm22c1to a distance that meets the proximal end of catheter hub4. Rails22e1and22e2are then bent slightly off at right angle downwardly to form a section adapted to contact the proximal end surface of catheter hub4. The end portion of rails22e1and22e2are further bent in the distal direction substantially transverse to the section adapted to contact the proximal end of catheter hub4such that end22e3is configured to be adapted to press against the flange4dof catheter hub4when barriers22d1and22d2are biased by needle12in the ready state, as per shown inFIG.5. Similarly, arm22c2is bent in a reverse manner such that rails22f1and22f2are bent upwardly at a slightly off right angle from the longitudinal portion of arm22c2to form a mid-section that defines a slot22f4with space sufficient to allow needle12to pass through at a distance proximal from rails22e1and22e2. The distal section22c2′ of arm22c2is configured in the shape of a hook2f3adapted to fittingly grasp the part of flange4dopposite to the part of the flange held by end22e3of arm22c1when needle clip22is coupled to catheter hub4in the ready state, as per shown inFIG.5. Hook22f3and distal section22c2′ of arm22c2pass though slot22e4of arm22c1.

Thus, as shown inFIGS.5and13a-13b, when the catheter assembly is in the ready state, barriers22d1and22d2are biased by needle12away from the longitudinal axis of the catheter assembly. Needle12also passes slots22f4and22e4of arms22c2and22c2, respectively, into catheter hub4. With barriers22d1and22d2biased outwardly, transverse portions22c1′ and22c2′ would move in opposite directions inwardly toward the longitudinal axis such that hook22f3catches flange4dand end22e3presses against flange4dof catheter hub4such that needle clip22and catheter hub4are coupled to each other. It should be appreciated that instead of one flange, there may be multiple flanges or protuberances provided at the proximal end of catheter hub4. In which case, hook22f3and end22e3would grasp opposite flanges. It should further be appreciated that hook22f3and end22e3are meant to illustrate grasping mechanisms that may be used. In practice, the arms each may have a hook at their distal end, or some other finger mechanisms that allow the needle clip to grippingly hold catheter hub4. Hook22f3and end22e3as discussed above may be referred to henceforth as grippers. It should furthermore be appreciated that needle clip22as described above may be adapted to be used for safety catheter assembles that do not have a sideport hub as per shown inFIGS.1-3, and CSC assemblies that have an external port that angles towards the open proximal end of the catheter hub and a tubing fixedly extending from the non-catheter hub end of the external port.

FIG.7ashows needle clip22and catheter hub4coupled to each other by means of dual finger hooks22f3instead of the single hook discussed above and shown inFIGS.5-6. Also, the end22e3of theFIG.5-6embodiment has been replaced by dual finger hooks22e3. Functionally, the finger hooks inFIGS.7a-7b,8a-8band9operate in the same manner as the grippers discussed with reference toFIGS.5-6.FIG.7bshows needle clip22housed inside clip guard14, which distal portion superposes over so as to cover and protect the proximal portion of catheter hub4. Of course, being housed inside clip guard14, needle clip22is also covered and protected by clip guard14. For illustration purpose, the catheter is removed from the distal end of catheter hub4so that a better view may be had for needle feature12cand distal tip12aof needle12.FIGS.7a-7bshow the catheter assembly in a ready state, or a ready to use position.

FIGS.8a-8billustrate the activated state of the needle assembly. InFIG.8a, needle12is shown to have been withdrawn in the proximal direction as indicated by directional arrow24. it is assumed that the distal tip of needle12has moved into the internal cavity of catheter hub4. At this point, since barriers22d1and22d2of needle clip22continue to be biased by needle12, hooks22f3and22c3remain in the position as shown so that catheter hub4and needle clip22remain coupled to each other.

FIG.8bshows needle12having been further withdrawn in the proximal direction such that distal tip12ais positioned proximal of barriers22d1and22d2and needle feature12cin contact with base22aof needle clip22, so that needle clip22moves in unison with the proximal movement of needle12. At this point, as barriers22d1and22d2are no longer biased by needle12, hooks22e3and22f3would return to their natural position so as to disengage from flange4dof catheter hub4. For the embodiment shown inFIG.8b, further movement of the needle in the proximal direction removes the needle clip from the catheter hub.FIG.9shows needle clip22housed inside clip guard14released from catheter hub4such that the catheter assembly is deemed to be in the safe state.

The catheter assembly with the needle clip embodiment shown inFIGS.5-6is further shown with reference toFIGS.10a-10b,11a-11band12a-12b.FIGS.10a-10bshow needle clip22housed inside clip guard14and catheter hub4being held by needle clip22in a ready or ready to use state. Clip guard14is removed fromFIGS.11a-11band12a-12bto illustrate with greater particularity the interaction between needle clip22and catheter hub4. In each ofFIGS.11a-11band12a-12b, as barriers22d1and22d2are biased by needle22, catheter hub4is coupled to needle clip22. Since needle clip22and the proximal end portion of catheter hub4are covered by clip guard14as per shown inFIGS.10a-10b, needle clip22is hidden from view from the time the catheter assembly is shipped in the ready state, during its use and to when the catheter hub is released from the needle clip to the disposal of the catheter assembly. After disposal, since needle clip22is housed within clip guard14and the distal portion of needle12including distal tip12ais entrapped in needle clip22, the distal tip of the needle is doubly prevented from being exposed to the environment.

With reference toFIGS.14-18, an alternative embodiment of the catheter assembly of the present invention is shown. In the alternate embodiment, components that are the same or function in the same manner as the earlier discussed embodiment are labeled with the same reference numbers. It should be appreciated that the exemplar catheter assembly shown inFIG.14is not the sideport catheter assembly as per shown inFIGS.1-3. It should further be appreciated that the clip guard embodiment ofFIG.14may be adapted to be used with different safety catheter assemblies, including the sideport catheter assembly shown inFIGS.1-3as well as a CSC assembly.

Similar to the earlier discussed catheter assembly, theFIG.14catheter assembly includes a catheter hub4, a needle12having a distal tip12aextending beyond the distal end of catheter10. Catheter hub4is captured by a needle clip22in the same manner as discussed above, as for example per shown inFIG.15. Needle clip22is housed in clip guard14, which is shown semi-transparently. Clip guard14in turn is received in distal portion6dof needle housing6. Needle clip22has the same components as the needle clip described inFIGS.5-6. To maintain needle clip22within chamber14bof clip guard14, a pair of opposing projections or tangs26extend distally at an angle from base22aof needle clip22. For the embodiment shown inFIG.15, undercuts28or other structure adapted to coact with tangs26are formed at opposing inner walls of clip guard14. When needle clip22is inserted into chamber14b, tangs26, when coming into contact with the tapered distal surfaces of undercuts28, would bend inwardly to pass the undercuts. Once past the undercuts, tangs26revert back to their unbiased natural position so that their respective edges26awould abut against the proximal back surfaces of the respective undercuts28to prevent needle clip22from moving in the distal direction relative to clip guard14. As a result, needle clip22is non-removably housed in chamber14bof clip guard14. Note that the opposing tangs26extend from opposing sides of base22awhile the arms22c1and22c2of needle clip22extend from the other opposing sides of base22a.

Further with respect to the embodiment shown inFIGS.14-18, a wiper member30that is made from an elastomeric material is fitted to the opened proximal end4cof catheter hub4. Wiper member30may henceforth be referred to as a nose wiper, an elastomeric member or simply a wiper. Wiper30, as best shown in the cross-sectional view ofFIG.17, has a distal portion or section30aand a proximal portion or section30b. Distal section30ahas a smaller dimension or cross section than the dimension of proximal section30b. The distal surface of proximal section30babuts against most of the proximal end surface of the flange4dat the proximal end of catheter hub4. The cross dimension of distal section30ais configured to enable distal section30ato be press fitted to internal cavity4fof catheter hub4, so that distal section30amay be frictionally held to the catheter hub.

As further shown inFIG.17, wiper30may also act as a retainer to prevent a seal member32positioned in internal cavity4fof catheter hub4from moving proximally relative to catheter hub4. As shown, seal member32inFIG.17has a membrane32athat reseals to prevent back flow of blood when needle12is removed from catheter hub4. In place of a seal member, a resealable septum may be positioned inside internal cavity4fof catheter hub4and be held thereat by wiper30. If the catheter assembly ofFIGS.14-18were a closed system catheter (CSC) assembly with an external port from the catheter hub but with no cylindrical sleeve covering the opening to the external port, the septum may be positioned in internal cavity4fproximal the opening of the external port to prevent blood back flow to the portion of the internal cavity proximal the septum when needle12is withdrawn from catheter hub4. While wiper30acts against the septum or seal member to prevent their movement in the proximal direction, an internal barrier for example an circumferential protrusion or shoulder at the inner wall of the catheter hub distal of and in abutment with the septum or seal member prevents the septum or seal member from moving in the distal direction. The septum, seal member and wiper are all made from elastomeric materials including for example silicone and polyisoprene, and each are formed as a unitary or monolithic component through various molding process including for example injection molding processes that are conventionally known.

Further with respect toFIGS.15-18, wiper30is shown to have two upper extensions or arms30cthat extend from the top of proximal portion30band two lower extensions or arms30dthat extend from the bottom of proximal portion30b. A hook or finger30c1is formed at the distal end of each of the upper arms30c, and a hook or finger30d1is formed at the distal end of each of the lower arms30d. The hooks30c1and30d1are configured to be in engagement with respective portions of the distal surfaces of flange4dsuch that wiper30is firmly held to catheter hub4. An opening or orifice30eis provided in wiper30to enable needle12to pass therethrough. The dimension of orifice30eis designed to be slightly smaller than the diameter of the needle so that the needle is in circumferential contact with the wall of orifice30eso that fluid such as blood that may have adhered to the needle is wiped off as needle12is withdrawn from catheter hub4. Thus, for the embodiment ofFIGS.14-18, needle12passes trough the bore of shaft14eof clip guard14(FIG.4b), the opening or aperture22bat base22aof needle clip22, and orifice30eof wiper30in the ready state. As discussed earlier, when needle12is withdrawn in the proximal direction relative to catheter hub4and distal tip12aof needle12is captured by the barriers22d1and22d2inside needle clip22, the hooks or hook/end combination of needle clip22are released from the flange4dof catheter hub4so that clip guard14with needle clip22non-removably housed in its chamber14bis separable from catheter hub4. Once separated from the catheter hub4, clip guard14is connected to needle housing6by the shaft of needle12, and the entrapped needle of the catheter assembly is deemed to be in the safe state or safe position.

Another embodiment of the present invention safety catheter assembly is shown with reference toFIGS.19-22. As is with the earlier embodiments, components that are the same or perform the same functions are labeled with the same reference numbers as above. The catheter assembly ofFIGS.19-22does not have a wiper, and is not a sideport catheter assembly or a CSC assembly.

As shown inFIGS.19-22, the catheter assembly has a catheter hub4that has side wings4aand at least opposing flanges4dat it proximal end4c. A catheter10extends from distal end4bof catheter hub4, and a needle12having a sharp distal tip12aextends beyond the distal end of catheter10. Also as discussed above, wall4eof catheter hub4defines an internal cavity4fthat has an opened proximal end4c. For the embodiment ofFIGS.19-22, a multiuse seal member32(also shown inFIGS.17-18) is provided within internal cavity4f. No wiper is provided at opened proximal end4cof catheter hub4.

Seal member32is a substantially cylindrical multiuse valve shown to include a proximal cylindrical portion32band a distal cylindrical portion32c. The portion of wall32dthat defines proximal portion32bis substantially uniform along its length, whereas the portion of wall32dthat defines distal portion32chas a corrugated shape and may be in the shape of an accordion along most if not all of its length. Membrane32ais integral of seal member32and partitions internal cavity4fof catheter hub4into respective bores of proximal portion32band distal portion32c. When fitted into the interior cavity4fof catheter hub4, given that the seal member32is made of an elastomeric material such as silicone or polyisoprene, accordion shaped distal portion32cis compressible when proximal portion32bis under pressure or its proximal end is impacted by a distal driving force. Distal portion32cand would return to its natural position when the pressure or impact force is removed from proximal end4c. Although shiftable axially, seal member32is non-removably secured to the interior cavity4fof catheter hub4, as an internal circumferential flange or shoulder32emay be provided at approximately the juncture between proximal portion32band distal portion32cto catchingly engage the step4hat interior cavity4fof catheter hub4. Step4hprevents seal member32from proximal movement out of catheter hub4once seal member32is fittingly inserted and seated into interior cavity4fby way of opened proximal end4cof catheter hub4.

The coupling of catheter hub4with needle clip22is done in the same manner as discussed above, in that opposing flanges4d(or portions of one flange) are grasped by hooks22f3at the distal ends of arms22c1and22c2of needle clip22. Other than hooks are provided at both distal ends of the arms (instead of a combination of hook/end as shown inFIGS.13a-13b), the coupling and decoupling of needle clip22and catheter hub4are the same as discussed above. Briefly, once distal tip12aof needle12is captured in needle clip22proximal to barriers22d1and22d2, hooks22f3of needle clip22are released from flange4dof catheter hub4so that further proximal movement of needle12relative to catheter hub4would cause needle clip and clip guard14to separate from catheter hub4. Needle clip22and clip guard14move in unison proximally from catheter hub4since needle clip22is non-removably housed in clip guard14due to the interaction of tangs26of needle clip22and undercuts28of needle clip22as discussed above.

The embodiment ofFIGS.19-22has a sheath36that covers the catheter hub and the distal portion of needle housing6when clip guard14is received in the ready state. As shown, sheath36has an enlarged semi-funnel shaped proximal portion having an internal dimension adapted to be frictionally held by the distal portion of clip guard14by means of its upright14fand the respective planar side surfaces and the bottom surface of clip guard14. It should be noted that the proximal end configuration of the clip guard14shown inFIGS.19-22is slightly different from the clip guard shown inFIGS.10a-10b, in particular with respect to the positioning of upright14f. Sheath36prevents damage to the catheter hub, the catheter and the needle during transit and is removed when the catheter assembly is to be used.

It is the intension of the inventors that all matter described throughout this specification and shown in the accompanying drawings be interpreted as illustrative only and not in a limiting sense. Accordingly, it is intended that the invention be limited only by the spirit and scope of the hereto appended claims.