Catheter connectors and systems, and methods of using same

Catheter connectors, systems, and methods of use in which a catheter is attached to a connector such that the catheter is retained on the connector by inward radial compression between an outer surface of a hollow pin located within the catheter and a collet fitted over the portion of the catheter containing the pin. The collet may be moved from an unlocked position to a locked position by axial displacement of the collet along a longitudinal axis of the connector.

TECHNICAL FIELD

The present invention relates generally to medical connection systems and, more particularly, to connectors, systems, and methods for connecting a catheter to another catheter or other device.

BACKGROUND

In many medical applications, it is necessary to connect one section of medical tubing, e.g., a catheter, with another. Generally speaking, it is important that these connections be relatively secure and stable so that the catheter does not separate or develop leaks. Security and leak-resistance take on elevated importance in applications where the catheters are implanted within a human body.

One procedure that necessitates implantation of a catheter into the body involves the use of an implantable medical device, e.g., a drug infusion pump. Such implantable medical devices are often used to control pain and/or spasticity, as well as to provide one or more drugs or fluid medications to a particular location within the body. A typical implant procedure may involve implanting a drug infusion pump into a cavity or subcutaneous pocket in the body and delivering a drug, via one or more catheters, to an epidural space or intrathecal space of the spinal column, or to a particular location within the brain.

An exemplary procedure may include positioning a first catheter at the desired location in the body and then connecting the first catheter to a second catheter via a connector. The connection may be made by inserting one end of the connector into a lumen of one catheter and the other end of the connector into the lumen of the other catheter and then sliding both catheter sections towards one another (toward the middle of the connector). The second catheter may then be connected to the drug infusion pump.

While adequate, difficulties have been encountered in the manufacture and use of such connectors. For example, one or both of the catheters may incorporate a braid in the catheter wall. The braid may provide various benefits including, for example, increased radial, longitudinal, and torsional stiffness. While these attributes are beneficial, the braid may also limit the expansion capacity of the catheter(s). As a result, radial expansion of the inner diameter of the catheters resulting from insertion of the ends of the connector into the catheter may be limited. Also, these connectors, which have been sized to fit within the lumens of the catheters, are small and may be difficult to manipulate by a clinician during implantation. Other potential problems may include lack of ability to adequately secure the catheters relative to the connector; and an inability to provide sufficient strain relief to the catheters at the connector. These issues may result in a weakened connection that is susceptible to catheter separation and/or leaks.

SUMMARY OF THE INVENTION

The present invention provides catheter connectors, connection systems, and methods in which a catheter is attached to a connector such that the catheter is retained on the connector by radial compression between a tube or pin located within the catheter and a collet positioned over the portion of the catheter containing the tube.

In one embodiment, a catheter connection system is provided and includes: a connector pin comprising a first end configured for insertion into a lumen of a catheter, the connector pin including an outer surface; a coupling sleeve configured to surround at least a portion of the catheter that contains the connector pin; and a tubular collet surrounding an end of the sleeve. The collet is movable along a longitudinal axis of the sleeve from an unlocked position to a locked position. The collet includes an outer ring; an inner ring; and an annular space between the inner and outer rings. The inner ring includes one or more segments that deflect inwardly to radially compress the catheter against the outer surface of the pin when the collet is in the locked position. In one configuration, the end of the sleeve is received within the annular space of the collet when the collet is in the locked position. The sleeve may define an inner surface having a tapered surface operable to slide along the one or more segments of the inner ring as the collet is moved from the unlocked position to the locked position. In another configuration, the connector pin is fixed within the sleeve. In yet another configuration, an outer surface of the sleeve comprises radially protruding elements. For instance, the radially protruding elements may be tabs that engage openings formed in the collet to secure the collet in the locked position. Alternatively or additionally, the radially protruding elements may include guide tabs configured to slide within slots in the collet. In still yet another configuration, the one or more segments of the inner ring may include four segments. In another configuration, the collet may define a passageway configured to receive the catheter and align the catheter with the first end of the connector pin. In still another configuration, the connector pin includes a tapered section transitioning the outer surface of the pin from a first diameter at the first end, to a second, larger diameter towards a center of the pin. In yet another configuration, the connector pin includes one or more circumferential barbs located proximate the first end. And in yet another configuration, the pin includes a second end for insertion into a lumen of a second catheter.

In another embodiment, a catheter connection system is provided that includes a connector body having: a tubular coupling sleeve including a wall defined by an inner surface and an outer surface, wherein the inner surface diverges to form an enlarged mouth at an end of the sleeve; and a tubular connector pin fixed relative to the inner surface of the sleeve such that an end of the pin extends outwardly into or beyond the enlarged mouth. The system further includes a catheter defining a lumen configured to receive the end of the connector pin therein. A first end of the catheter is located within the enlarged mouth of the sleeve when the end of the connector pin is received within the lumen of the catheter. A tubular collet is also included and is configured to both: surround a portion of the catheter containing the connector pin; and interlock with the sleeve. The collet is movable along a longitudinal axis of the sleeve from an unlocked position to a locked position. The collet includes an outer ring; an inner ring; and an annular space between the inner and outer rings, wherein the end of the sleeve is received within the annular space when the collet is in the locked position. In one configuration, the mouth defines a tapered surface that diverges towards the end of the sleeve. In another configuration, the tapered surface is configured to slide along the inner ring and deflect the inner ring radially inwardly as the collet is moved to the locked position. In yet another configuration, an outer surface of the pin comprises a tapered section, while in another configuration, an outer surface of the pin includes a circumferential barb. In still another configuration, the connector pin includes a second end extending into an enlarged mouth at a second end of the sleeve, wherein the system further includes: a second catheter defining a lumen configured to receive the second end of the pin; and a second collet associated with the second end of the sleeve.

In yet another embodiment, a therapeutic substance delivery system is provided that includes: an implantable medical device; a delivery catheter for coupling with the medical device; and a catheter connector. The connector includes: a connector pin comprising a terminal end configured for insertion into a lumen of the delivery catheter, the connector pin including an outer surface; a coupling sleeve configured to surround at least a portion of the delivery catheter that contains the connector pin; and a tubular collet surrounding an end of the sleeve. The collet is movable along a longitudinal axis of the sleeve from an unlocked position to a locked position. The collet further includes an outer ring; an inner ring; and an annular space between the inner and outer rings. The inner ring includes one or more segments that deflect inwardly to radially compress the delivery catheter against the outer surface of the pin when the collet is in the locked position. In one configuration, the catheter connector forms part of the medical device. In another configuration, the catheter connector couples the delivery catheter to a therapy catheter.

In still yet another embodiment, a method of connecting a catheter to a tubular connector pin is provided and includes: inserting an end of the connector pin into a lumen of the catheter, the connector pin surrounded by a coupling sleeve radially spaced-apart from the end of the connector pin; and sliding a tubular collet over the sleeve from an unlocked position to a locked position, wherein the collet comprises an outer ring; an inner ring; and an annular space between the inner and outer rings, and wherein the inner ring includes one or more deflectable segments. The method further includes: locating an end of the sleeve in the annular space of the collet; contacting the inner ring of the collet with an inner surface of the sleeve; deflecting the one or more deflectable segments radially inwardly; and compressing the catheter against an outer surface of the pin. In one configuration, the method further includes engaging a tab associated with the sleeve with an opening associated with the collet when the collet reaches the locked position. In another configuration, contacting the inner ring of the collet with the inner surface of the sleeve includes contacting the inner ring with a tapered surface of the inner surface of the sleeve.

The above summary is not intended to describe each embodiment or every implementation of the present invention. Rather, a more complete understanding of the invention will become apparent and appreciated by reference to the following Detailed Description of Exemplary Embodiments in view of the accompanying figures of the drawing.

The figures are rendered primarily for clarity and, as a result, are not necessarily drawn to scale.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

In the following detailed description of illustrative embodiments of the invention, reference is made to the accompanying figures of the drawing which form a part hereof, and in which are shown, by way of illustration, specific embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present invention.

As used herein, “a,” “an,” “the,” “at least one,” and “one or more” are used interchangeably. The term “and/or” (if used) means one or all of the listed elements or a combination of any two or more of the listed elements. Moreover, where convenient, similar or identical components that are identified with the same reference numeral may be distinguished with the suffix “a” (e.g.,102a). It is understood that a component having such a suffix is, however, similar or identical to the component without the suffix. Further, the description of a component (e.g., catheter102) provided herein is understood, unless, otherwise stated, to apply to both components (e.g., both to the component without the suffix (102) and to the component with the suffix (102a)).

Illustrative embodiments of the present invention include a tubing connector and system for coupling sections of tubing, and to methods for using the same. In one embodiment, the connector provides a pin that may fit into each tubing section. A coupling sleeve associated with the pin may be located over a portion of the pin and the section(s) of tubing into which the pin extends. One or more tubular collets surrounding one or both ends of the sleeve may then slide, relative to the sleeve, and interlock with the same. The collets, via the sleeve, may radially compress the sections of tubing against the pin, thereby providing a compression force to seal the tubing to the pin and secure the various components in place. In one embodiment, the interlocking of the collets with the coupling sleeve may occur without the use of tools.

FIG. 1is a perspective view of a catheter connection system100in accordance with one embodiment of the invention. As shown in this figure, the system100may include a connector101that securely interconnects a first medical tube, e.g., first or delivery catheter102, with a second medical tube, e.g., second or therapy catheter102a. The exemplary connector101may include a tubular connector pin106(seeFIG. 3) and associated tubular coupling sleeve108(also seeFIG. 3), which together form a connector body103, and two tubular connectors or collets110. The sleeve108is, in one embodiment, configured to surround at least a portion of the catheter(s) that contains the connector pin106as further described below. The components102,106,108, and110may, when assembled, lie along a longitudinal axis112as shown inFIG. 1. Embodiments of the components, connectors, and systems described herein may be sized for implantation within a typical human or other mammalian body.

Although the system100is illustrated as incorporating a two-sided connector, i.e., the illustrated connector101, includes a collet110on each of two opposing ends, other embodiments may utilize a connector having a collet on only one end without departing from the scope of the invention, e.g., a single-sided connector. Exemplary two-sided connectors101may be used to, for instance, couple two catheters together, e.g., first and second catheters102,102athat couple an implantable medical device (e.g., an implantable infusion pump200such as a SynchroMed® II programmable infusion pump distributed by Medtronic, Inc., of Minneapolis, Minn. USA) to a remote drug delivery site, as shown in the therapeutic substance delivery system201ofFIG. 2A. A single-sided connector1101may, on the other hand, be utilized to connect a component (e.g., a pump300of a delivery system301) to a catheter (catheter102) as shown inFIG. 2B. In case of the latter, the connector1101, e.g., the body of the connector, may be an integral component of the pump300(or otherwise attached thereto).

In yet other embodiments of the present invention, a connector system may again be configured as a two-sided connector, but include different connector structures on each side. For example, one side of the connector may be configured in accordance with an embodiment of the present invention, while the other side of the connector may include an entirely different connector structure.

In still other embodiments, the connector may include more than two sides. For instance, the connector body could form a “Y”-connector including three or more sides, one or more of which may be a connector in accordance with an embodiment of the present invention.

FIG. 3illustrates the exemplary connector101and connection system100ofFIG. 1in an exploded view. While the sleeve108(as well as the remaining components of the connection system100) is shown as having a generally circular cross-sectional shape, any suitable cross-sectional shape could be utilized (e.g., octagonal, elliptical, oval, etc.). However, for reasons that will become clear, regardless of the shape of the sleeve, the engaging portions of the collets110will typically include a complementary shape to permit the desired attachment.

As discussed herein, the illustrated system100includes a catheter (102,102a) extending from both sides of the connector (although, once again, single and other multi-sided connectors are contemplated). For brevity, however, the description of the connector100may, where appropriate, focus on a single side, with the understanding that the opposite side, if present, is similar or identical.

Each catheter102may be of conventional construction, e.g., an elastomeric tubular body made from a polymer (pure or blended), silicone, or the like. The catheter may define a lumen114extending end-to-end such that fluids may be delivered through the catheter from one end to the other. One or both catheters may include features, e.g., strengthening braids, multiple layers, additives, etc., to satisfy the particular requirements of the intended application. That is, the construction of the catheters may vary without departing from the scope of the invention. In one embodiment, however, the catheters may be constructed in accordance with, and otherwise similar to, any of the catheter embodiments described and/or illustrated in US Pat. App. Pub. No. US 2008/0275429 A1 (Sage), which is incorporated herein by reference in its entirety.

In the illustrated embodiment, the pin106is fixed relative to an inner surface115of the sleeve108, e.g., molded with or otherwise permanently attached to the sleeve, to form the body103. As evident in the figures (see, e.g.,FIG. 4), the pin106may be sized where its terminal end(s)104extends outwardly into or beyond an enlarged mouth118of the sleeve, resulting in the sleeve being radially spaced-apart from the end of the pin. In the illustrated embodiment, the end of the pin106may actually protrude a short distance beyond each end of the sleeve108. However, embodiments wherein the pin is the same length, or even shorter, than the sleeve are certainly possible without departing from the scope of the invention.

As indicated inFIG. 3, each catheter102,102amay connect to an end (first end104and second end104a, respectively) of the tubular pin106by insertion of the opposing first and second ends of the pin into the respective lumens114of the catheters. Stated alternatively, each end of the pin is configured for insertion into the lumen of one of the catheters, and the lumen of each catheter is likewise configured to receive therein an end of the pin. As the pin is hollow (e.g., forms a lumen along its entire length), fluids may thus flow from one catheter through the pin to the other catheter when the connector is fully assembled.

As further shown inFIG. 3, a collet110may be associated with at least one end of the sleeve108and with at least one of the medical tubes (e.g., one of catheters102,102a). In the two-sided connector illustrated inFIG. 3, a collet and a catheter are associated with each end of the sleeve. As described in more detail below, once the catheters are placed over to the ends of the pin106, the sleeve108surrounds the pin106and the portions of the catheters102that overlap with the pin. Each collet110may then be slid towards the center of the sleeve108(along the longitudinal axis112) until it interlocks with the sleeve as further described below. Thus, the collet110may both: surround a portion of the catheter containing the pin106; and interlock with the sleeve108. Interlocking of the collets110with the sleeve108may radially compress the catheters102,102aagainst the pin106, resulting in a strong and leak-free connection.

With this brief introduction, an exemplary embodiment of the connector will now be described with reference primarily toFIGS. 4-7.FIG. 4illustrates a cross sectional view of the body103(e.g., sleeve108and pin106) as taken through the longitudinal axis112, andFIG. 5illustrates an end view of the body taken along line5-5ofFIG. 4. As discussed herein above, the pin106of the illustrated embodiment is not intended for removal from the sleeve, i.e., the two parts may be permanently attached. In the illustrated embodiment, this attachment may be achieved by molding the pin to the sleeve. However, other methods of attachment, e.g., staking, adhering, press-fits, etc., are certainly possible without departing from the scope of the invention.

The pin106may be of a size and material that prevents collapse of the pin under application of radial compression loads applied by the sleeve108and collet110as further described below. For instance, in one embodiment, the pin is an 80-20 Platinum-Iridium alloy having an inner diameter of about 0.2 millimeters (mm) to about 0.4 mm (e.g., about 0.33 mm) and an outer diameter (measured near each end) of about 0.4 mm to about 0.8 mm (e.g., about 0.48 mm). The pin106may further be about 17 mm to about 22 mm (e.g., about 20 mm) long and may include an outer surface having one or more radially protruding, circumferential barbs117located proximate each end of the pin as shown inFIG. 4. The pin may additionally include one or more tapered sections116spaced inwardly from the each end of the pin (e.g., inboard from the barbs). Each tapered section116may transition the outer surface of the pin from a first diameter at the end of the pin, to a second larger diameter towards a center of the pin.

The barbs117may assist with retention of the catheters102once the ends of the pin106are inserted therein. The tapered sections116, on the other hand, may provide increased interference between the pin and the catheters as the latter are slid over the pin. This increased interference may provide feedback (e.g., resistance to sliding) to the clinician as to when the pin106has been adequately inserted into its respective catheter. The tapered sections116may further provide a transition to a larger diameter towards the center of the pin that is beneficial to the manufacture of the body103. Once again, while the pin106is described with some particularity herein, such a construction is intended to be exemplary only as other materials (e.g., titanium), sizes, and configurations are certainly contemplated.

As illustrated inFIG. 4, the sleeve108may also form a tubular member having a wall114defined by an outer surface113and the inner surface115. While again not wishing to be bound to any particular configuration, the sleeve108may, in one embodiment have an outer diameter (measured near its center) of about 2 mm to about 5 mm (e.g., about 2.5 mm). The sleeve may further have a length (measured along the longitudinal axis112) of about 15 mm to about 20 mm (e.g., about 17.5 mm). With the pin106secured within the sleeve108as shown inFIG. 4, the sleeve may surround portions of the pin and, when assembled with the catheters102, portions of the catheters that overlap with the pin (see, e.g.,FIG. 9). In one embodiment, the pin106may protrude longitudinally about 1 mm to about 5 mm beyond each end of the sleeve108.

The inner surface115may have a profile that varies along a length of the sleeve108. For instance, at one or both ends of the sleeve108, the inner surface115may transition or expand to form the enlarged mouth118. This transition may be accommodated in a variety of ways. For instance, in one embodiment, the inner surface115may include a tapered portion or surface120that tapers from the mouth118inwardly towards a center portion of the sleeve (e.g., diverges towards the end of the sleeve). The inner surface115, e.g., the mouth118, may optionally include a transition area123extending inwardly from the tapered surface120to a step surface122that is, in one embodiment, perpendicular to the longitudinal axis112of the sleeve. In one embodiment, the transition area of the sleeve108is defined by a generally uniform diameter as shown inFIG. 4that is of a diameter sufficient to receive the catheter and permit it some degree of axial movement during catheter connection.

The sleeve108may further include features that permit and assist with mechanical coupling of the sleeve with the collets110. For instance, in one embodiment, the outer surface113may form one or more radially protruding elements, e.g., tabs124, which extend away from the longitudinal axis112as shown inFIGS. 4 and 5. The outer surface113of the sleeve108may optionally define one or more secondary tabs128. As described below, the tabs124may each foam a surface126that, along with the secondary tab128, interact with corresponding features of the collet110. In the illustrated embodiment, the secondary tabs128allow the collet110to be pre-mounted onto the sleeve108. Pre-mounting the collet to the sleeve may not only reduce the presence of otherwise loose and separate parts, it also provides an alignment feature to assist with placing the catheter over the pin.

As shown inFIG. 5, each end of the body103may include both a tab124and a tab128at two separate locations that are spaced180degrees from one another. Other embodiments may include more or less tabs without departing from the scope of the invention.

In the illustrated embodiment, other radially protruding elements, e.g., guide tabs130, may also be included. For instance, each end of the sleeve may include two guide tabs130evenly spaced from the tabs124(e.g., spaced90degrees to each side of the tabs124). The guide tabs130, as explained below, may fit and slide within slots132(seeFIG. 3) formed in the collets110to index the collets relative to the connector body103, thereby preventing incorrect assembly.

FIGS. 6 and 7illustrate, respectively, a cross-sectional view and a perspective view of the exemplary collet110. The collet110may, in one embodiment, form a tubular cup-shaped member that is formed by an outer ring134and an inner ring136. Between the inner and outer rings an annular space138may be formed. A passageway140extends completely through the collet110(e.g., through the inner ring136) along the longitudinal axis112to accommodate the catheter102and pin106as further described herein.

With reference toFIG. 6, the outer ring134may also define a series of openings, e.g., first and second openings142and144. These openings may interact with the tabs124and128as further described below. The outer ring134may further define the slots132as already described above. The slots may visually divide the outer ring into two halves (see, e.g.,FIG. 3).

The inner ring136may be partitioned into multiple semi-cylindrical segments or members146by slots148. In the illustrated embodiment, the inner ring136has four slots148that partition the ring into four cantilevered segments146(seeFIG. 7). Those of skill in the art, however, will realize that more or less segments146may be formed without departing from the scope of the invention.

As shown inFIG. 7, an inner side of the outer ring134may also include slots150aligned with the openings142and144. These slots150may accommodate the protruding structure supporting the tabs124and128(seeFIG. 3) to permit sliding engagement of the collet110over the sleeve108.

While not wishing to be bound to any particular material, both the sleeve108and collets110may, in one embodiment, be made from nylon 12 (sold under the trade name Grilamid TR55 by EMS-Grivory of Switzerland).

A method of using the exemplary connector101will now be described primarily with reference toFIGS. 3,8, and9. The connector101may be supplied with the collet(s)110attached to the body103and positioned in an unlocked position as shown inFIG. 8. In this manner, the body103and collet(s)110may be assembled and enclosed in a single sterile package. As further described herein, each collet110may be movable, e.g., slidable, along the longitudinal axis112of the sleeve108from the unlocked position ofFIG. 8to a locked position as shown inFIG. 9and as described in more detail below.

In the unlocked position, the collet110may be positioned on the sleeve108such that the secondary tab128is aligned with the opening142formed in the collet. The engagement of the secondary tab128with the opening142is sufficient to hold the collet110in the unlocked position until the clinician positively advances the collet to the locked position as further explained below. The tab124may also assist in holding the collet110in the unlocked position by contact with the edge of the collet as shown inFIG. 8.

To couple the catheter102to the connector101, the catheter102may be received into the passageway140formed in the collet110as represented by the direction arrow152inFIG. 8. The diameter of the passageway140may be sized to assist with aligning the catheter102(e.g., the lumen114of the catheter) with the end104of the pin106so that the pin may be more easily inserted into the lumen of the catheter.

As the catheter102is slid sufficiently onto the pin106, it eventually passes over the barbs117and ultimately, engages the tapered section116. The tapered section116may provide further resistance to catheter advancement, providing the clinician with feedback that the catheter102has been adequately received over the pin106. If the catheter is advanced further, it may eventually abut the step surface122. When the pin106is adequately received within the lumen114of the catheter102, the catheter is located within the enlarged mouth118of the sleeve as shown inFIG. 9.

With the catheter102attached to the pin106, the collet110may then be advanced, e.g., slid, towards the center of the body103, e.g., in the direction154indicated inFIG. 9. As the collet is advanced from the unlocked position ofFIG. 8to the locked position ofFIG. 9, the outer ring134of the collet may ride over the tab124until the tab124engages the opening142. Each tab124may include a ramped surface125(seeFIG. 9) to assist with advancement of the collet. Once the collet is advanced to the locked position shown inFIG. 9, the tab124associated with the sleeve is aligned and engaged with the opening142of the collet and the tab128is aligned and engaged with the opening144. At this point, the surface126of the tab124is in abutment with an inner surface of the opening142. The surface126may be generally perpendicular to the longitudinal axis to provide positive latching (e.g., a ratcheting or snap-fit connection) of the collet to the body103. Such positive latching may be indicated, for example, by tactile, audible, or visual cues. The surface126is also constructed so that retraction of the collet (e.g., return of the collet to the unlocked position ofFIG. 8) is difficult or nearly impossible (short of damaging or destroying one or more components).

As the collet110advances from the unlocked position to the locked position, the inner ring136of the collet enters the mouth118of the sleeve108and the end of the sleeve is received within the annular space138(seeFIGS. 6 and 8) formed between the inner ring and the outer ring134of the collet. As a result, the tapered surface120slides along the inner ring, e.g., along the segments146(FIG. 6) that form the inner ring. The tapered surface120causes the segments146of the inner ring to deflect inwardly to radially compress the catheter102against the outer surface of the, pin106(as the collet is moved towards the locked position as illustrated inFIG. 9). In one embodiment, the compressive force applied by the segments146is at least partially distributed over a portion of the catheter that is at or near (and, in one embodiment, slightly inboard of) the barbs117. Accordingly, the catheter is securely attached to the pin by a radial compressive force applied by the sleeve108of the body103to the segments146.

In one embodiment, the method may also include tunneling subcutaneously a proximal end of the catheter102(see, e.g.,FIG. 2B), which has its opposite or distal therapy-delivering end implanted at the desired anatomical location, to the area where the implantable pump300is positioned. This proximal end may then be coupled to the connector1101of the pump in accordance with methods described above. In yet another embodiment (e.g., where the connector is configured as a two-sided connector101as shown inFIG. 2A), the method may include positioning the therapy-delivering end of the catheter102ain a similar manner such that its proximal end may couple to a first side of the connector101. In this embodiment, the method may also include coupling a distal end of the catheter102to a port of the implanted pump200and its opposite or proximal end to a second side of the connector101as described herein.

To remove the connector101, the catheter(s)102may be cut and the connector disposed of. Alternatively, a medical instrument, e.g., forceps, may be used to push the tab128radially inwardly and/or the collet may be deformed sufficiently to permit the collet to return to the unlocked position. At this point, the catheters may be retracted from the pin106or cut and removed.

As illustrated inFIG. 9, the collet110, when in the locked position, may extend beyond the length of the pin106. As a result, the catheter102is provided with some degree of strain relief to reduce potential damage to the catheter from the end of the pin.

Illustrative embodiments of this invention are discussed and reference has been made to possible variations within the scope of this invention. These and other variations, modifications, and combinations of the invention will be apparent to those skilled in the art without departing from the scope of the invention, and it should be understood that this invention is not limited to the illustrative embodiments set forth herein. Accordingly, the invention is to be limited only by the claims provided below and equivalents thereof.