Patent Description:
Various types of access devices for introducing and/or delivering a medical article have been described, with varying functionality. For instance, <CIT> discloses an introducer sheath set comprising a guide member, a dilator and a sheath, <CIT> shows a locking apparatus for use with a catheter assembly, <CIT> discloses a guidewire system comprising a guidewire jacket, at least two guidewires, and a handle adapted to lock the two guidewires together, and <CIT> shows a medical guide element with a diameter transition to prevent advancement past a chosen point.

A preferred non-claimed method for inserting a catheter or vascular sheath into a blood vessel involves the use of the Seldinger or a modified Seldinger technique, which includes an access needle that is inserted into a patient's blood vessel. A guidewire is inserted through the needle and into the vessel. The needle is removed, and a dilator and sheath in combination or separately are then inserted over the guidewire. The dilator and sheath, together or separately, are then inserted a short distance through the tissue into the vessel, after which the dilator and guidewire are removed and discarded. A catheter or other medical article may then be inserted through the sheath into the vessel to a desired location, or the sheath may simply be left in the vessel.

The above technique requires exchanges over the guidewire, which presents the risk of losing cannulation, lost guidewire, and contamination. The overall technique is time intensive risking movement of the medical article(s) and guidewire relative to the patient. Thus, there exists a need for an easier-to-use and safer vascular access device, especially one that would reduce accidental embolization and other attendant risks of over- wire vascular access.

The access devices described herein advantageously provide improved mechanisms for safely achieving medical device placement within the vasculature. Without limiting the scope of this disclosure, its more prominent features will be discussed briefly. After considering this discussion, and particularly after reading the Detailed Description of the Preferred Embodiments section below in combination with this section, one will understand how the features and aspects of these embodiments provide several advantages over prior access devices.

The invention is directed to an access device for placing a medical article within a body space, as defined in claim <NUM>. Further advantageous embodiments are defined in the dependent claims. The access device includes a dilator having a hub and an elongated dilator body extending from the hub. The access device further includes a guidewire configured to slide within the dilator body and having a guidewire stop. The access device further includes a locking mechanism supported by the dilator and having a guidewire lock. The locking mechanism is configured to interlock with the guidewire at least when the dilator is threaded over the guidewire and the guidewire lock axially aligns with the guidewire stop.

The access device includes a guidewire having a guidewire stop and a dilator configured to be coaxially disposed about the guidewire. The access device further includes a locking mechanism disposed on the dilator and configured to move from an unlocked state to a locked state. The locking mechanism is disengaged from the guidewire when the locking mechanism is in the unlocked state so as to allow axial movement by the guidewire through the locking mechanism in a proximal direction and a distal direction. The locking mechanism is engaged with the guidewire when the locking mechanism is in the locked state so as to limit at least axial movement of a portion of the guidewire in the distal direction relative to at least a portion of the dilator.

A non claimed method of limiting a distance a guidewire can be advanced out of a distal end of a dilator and into a patient's body is also described therein. The method includes puncturing a patient's body with a needle having an interior bore, sliding a guidewire through the interior bore and into the patient's body, and removing the needle from the patient's body. The method further comprises threading a dilator over the guidewire and into the patient's body. The dilator includes a locking mechanism configured to receive the guidewire and interlock to the guidewire so as to inhibit at least relative axial movement between at least a portion of the guidewire and at least a portion of the dilator in one direction.

The locking mechanism may comprise an attachment connecting to at least one area of the guidewire so that the guidewire cannot be inadvertently advanced too far into the patient, resulting in intravascular guidewire loss or embolization.

The locking mechanism can be configured to maintain a maximum guidewire length beyond the needle tip when advanced. The locking mechanism can be configured to retain the guidewire to the access device so that the guidewire is not misplaced or lost in the patient's body.

In some embodiments, the locking mechanism (which can be adjustable) limits the extent to which the guidewire can be moved (e.g., advanced) relative to the needle. In some modes, a groove or recess can be disposed at a proximal region of the guidewire to inhibit the proximal region from disengaging from the locking mechanism and entering the patient. In other modes, the groove or recess can be positioned at other locations along the guidewire to help regulate the length of guidewire that can be advanced from the needle tip. Preferably, an interaction (e.g., interference, engagement, friction, mechanical coupling, adhesion, etc.) exists between the guidewire and the locking mechanism to inhibit relative movement between these components.

These and other aspects of the present invention will become readily apparent to those skilled in the art from the following detailed description of the preferred embodiments, which refers to the attached figures. The invention is not limited, however, to the particular embodiments disclosed, as long as they fall under the scope of the appended claims.

These and other features, aspects, and advantages of the access device disclosed herein are described below with reference to the drawings of various embodiments, which are intended to illustrate and not to limit the invention. Additionally, from figure to figure, the same reference numerals have been used to designate the same components of an illustrated embodiment. The following is a brief description of each of the drawings.

The present disclosure provides an access device for the delivery of a medical article (e.g., catheter or sheath) to a blood vessel or drainage site. <FIG> illustrates an access device <NUM> that is configured to be inserted into a blood vessel (e.g., a vein or an artery) in accordance with an embodiment discussed herein. While the access device is described below in this context (i.e., for vascular access), the access device also can be used to access and place a medical article (e.g., catheter or sheath) into other locations within a patient's body (e.g., a drainage site) and for other purposes (e.g., for draining an abscess).

The access device, in some embodiments, is disclosed in the context of placing an exemplary single-piece, tubular medical article into a body space within a patient. Once placed, the tubular article can then be used to receive other medical articles (e.g., catheters, guidewires, etc.) to provide access into the body space and/or be used to provide a passage way for introducing fluids into the body space or removing (e.g., draining) fluids from the body space. As shown in the illustrated embodiment, the tubular medical article can be a sheath or catheter that is configured primarily to provide a fluid passage into a vein. However, the current disclosure should not be interpreted as being limited to the placement of single piece sheaths or catheters, or to the subsequent insertion of a medical article via the sheath or catheter. Instead, it will be understood by one of skill in this art, in light of the current disclosure, that the access device disclosed herein also can be successfully utilized in connection with placing one or more other types of medical articles, including other types of sheaths, fluid drainage and delivery tubes, and single or multi-lumen catheters directly in the patient or indirectly via another medical article.

For example, but without limitation, the access device disclosed herein can be configured to directly or indirectly place central venous catheters, peripherally inserted central catheters, hemodialysis catheters, surgical drainage tubes, tear-away sheaths, multi-piece sheaths, scopes, as well as electrical conduit for wires or cables connected to external or implanted electronic devices or sensors. The medical articles listed herein may be directly placed in the patient via the dilator and guidewire of the access device or subsequently placed within the patient via a medical article that was placed within the patient via the dilator and guidewire of the access device.

The embodiments disclosed herein are not limited to co-axial insertion of a single medical article. For example, two catheters may be inserted in the patient via an inserted sheath or a second catheter may be inserted in the patient via an inserted first catheter. In some instances, the medical article inserted via the dilator and guidewire can form a lumen that is in addition to the lumen(s) of the subsequently inserted medical article. One skilled in the art can also find additional applications for the devices and systems disclosed herein. Thus, the illustration and description of the access device in connection with a sheath (e.g., for micro puncture applications) is merely exemplary of one possible application of the access device.

<FIG> is a perspective view of an embodiment of an access device <NUM> that includes a dilator <NUM> coaxially aligned with a sheath <NUM>. A guidewire <NUM> is also shown. The components of the access device <NUM> illustrated in <FIG> include a dilator <NUM> and a sheath <NUM>. In the illustrated embodiment, the access device <NUM> also includes the guidewire <NUM>. The sheath <NUM> can be coaxially mounted on the dilator <NUM>. The telescoping nature of the access device's components can also be accomplished by arranging the components with their axes arranged substantially parallel rather than coaxially (e.g., a monorail-type design).

Each of these components includes a luminal fitting at a terminal end or transition (e.g., a hub) and elongated structure that extends from the fitting. Thus, in the illustrated embodiment, the dilator <NUM> includes a dilator shaft <NUM> that extends distally from a dilator hub <NUM>, and the sheath <NUM> includes a sheath body <NUM> that extends distally from a sheath hub <NUM>. In certain embodiments, the guidewire <NUM> includes a guidewire hub or cap.

With reference to <FIG>, the access device <NUM> further includes a stopper or locking mechanism <NUM>. The locking mechanism <NUM> provides one or more interlocks or interconnections between the locking mechanism <NUM> and the guidewire and/or one or more other components of the access device <NUM>. In certain embodiments, the locking mechanism <NUM> provides a first interlock between the locking mechanism <NUM> and the guidewire <NUM>. In certain embodiments, the locking mechanism <NUM> further provides a second interlock between the locking mechanism <NUM> and another component of the access device <NUM>. For example, in certain implementations the first and second interlocks of the locking mechanism <NUM> can engage with the guidewire <NUM> and the dilator <NUM>, respectively. The locking mechanism <NUM> need not include both first and second interlocks. In certain embodiments, the locking mechanism <NUM> further locks to another component of the access device <NUM>. For example, the locking mechanism <NUM> can include an interlock for locking to the sheath <NUM>.

The phrase "interlock" means a feature of the locking mechanism <NUM> which inhibits movement of the locking mechanism <NUM> in at least one direction relative a component of the access device <NUM>. An interlock can be an interaction (e.g., interference, engagement, friction, mechanical coupling, mechanical interconnection, mechanical interplay, adhesion, etc.). In certain embodiments, for example, such features include one or more structures of the locking mechanism <NUM> such as tabs, teeth, grooves, etc. as well as a size or shape of the locking mechanism <NUM> itself. For example, an outer portion of the locking mechanism <NUM> could be sized and shaped so as to inhibit movement of the locking mechanism <NUM> relative to an inner surface of a component of the access device <NUM> via contact between the outer portion and the inner surface.

The locking mechanism <NUM> is configured to inhibit a proximal portion of the guidewire <NUM> from being advanced too far through the dilator <NUM>. Advancing the guidewire <NUM> beyond a proximal end of the dilator <NUM> risks the possibility of intravascular guidewire loss. Further, even if the guidewire <NUM> is not advanced beyond the proximal end of the dilator <NUM>, when the dilator <NUM> is withdrawn from the sheath <NUM> there is a risk that any friction occurring between flowing blood and a portion of the guidewire <NUM> inserted into the vasculature will draw the guidewire <NUM> into the vasculature. In certain embodiments, the locking mechanism <NUM> allows the guidewire <NUM> to be withdrawn from the access device <NUM> generally simultaneously with the dilator <NUM>.

In certain embodiments, an advanced guidewire <NUM> is inhibited from being withdrawn back into the dilator <NUM>. For example, the interlock between the locking mechanism <NUM> and the guidewire <NUM> can inhibit proximal and/or distal movement of the guidewire <NUM> relative to the dilator <NUM>. Such an arrangement can reduce the risk of breaking off a distal end of the guidewire <NUM> and having the distal end of the guidewire <NUM> enter the vasculature.

<FIG> is side view of a needle <NUM> which can be employed to facilitate insertion of the guidewire <NUM> from <FIG> into a patient. <FIG> is a side cross-sectional view of the needle <NUM> of the embodiment depicted in <FIG> taken along line 2B-2B. The needle <NUM> includes a needle body <NUM> and a needle hub <NUM>. As best seen in <FIG>, the needle hub <NUM> is disposed on a proximal end of the needle body <NUM>. The needle body <NUM> terminates at a distal end near a distal portion <NUM> of the needle <NUM>, and the needle hub <NUM> lies at a proximal portion <NUM> of the needle <NUM>.

The needle body <NUM> preferably has an elongated tubular shape having a circular, constant-diameter interior bore <NUM> and a circular, constant-diameter exterior surface. In other embodiments, however, the needle body <NUM> can have other bore and exterior shapes (such as, for example, but without limitation, an oval cross-sectional shape). The interior or exterior of the needle <NUM> can also include grooves or channels. The grooves or channels may guide fluids within the needle bore either around or to certain structures of the needle <NUM> or within the needle <NUM> (e.g., around the guidewire <NUM>). In some embodiments, the grooves or channels may assist in maintaining a desired orientation of the needle <NUM> with respect to the dilator <NUM>.

The needle body <NUM> has a sufficiently long length to access a targeted subcutaneous body space and has a sufficient gauge size to withstand the insertion forces when accessing the body space without causing undue trauma. For many applications, the needle body <NUM> can have a length between <NUM>- <NUM> (e.g., between <NUM>-<NUM>). For example, to access a body space (e.g., a vessel) in the thorax of an adult human, the needle body <NUM> preferably has a length of <NUM> or greater, and more preferably has a length of <NUM> or greater, and most preferably has a length of <NUM> to <NUM>. The size of the needle <NUM> preferably is <NUM>,<NUM> (<NUM> gauge) or smaller (e.g., between <NUM>,<NUM>-<NUM>,<NUM> (<NUM>-<NUM> gauge) or between <NUM>,<NUM>-<NUM>,<NUM> (<NUM>-<NUM> gauge) for micro-puncture applications (peripheral IVs)). For applications with a neonate, the length and gauge of the needle body <NUM> should be significantly shorter and smaller, for example between <NUM>-<NUM> and between <NUM>,<NUM>-<NUM>,<NUM> (<NUM>-<NUM> gauge). The needle body <NUM> can have a bevel tip <NUM> disposed on the distal portion <NUM>.

As explained below in greater detail, the guidewire <NUM> is introduced through a hollow portion <NUM> of the needle hub <NUM>, through the needle body <NUM>, and into a punctured vessel. After removing the needle <NUM> from the patient, the remaining guidewire <NUM> allows the healthcare provider to guide the dilator <NUM> and sheath <NUM> into the vessel.

<FIG> is a plan view of a dilator <NUM> that can be used with the access device <NUM> of <FIG> and includes a locking mechanism <NUM>. <FIG> is a side cross- sectional view taken along the lines 3B-3B in <FIG>. The illustrated dilator <NUM> comprises a dilator shaft <NUM>, a dilator hub <NUM>, a distal region <NUM>, and a proximal region <NUM>.

<FIG> is an enlarged view of a portion of the dilator <NUM> illustrated in <FIG> which is circled by line 4A-4A. The dilator <NUM> includes a receptacle <NUM>. In certain embodiments, the receptacle is configured to receive the locking mechanism <NUM>. However, the locking mechanism <NUM> need not reside within the dilator <NUM>. In certain embodiments, the locking mechanism <NUM> resides on top of the dilator <NUM> or outside the dilator <NUM> as long as the guidewire <NUM> passes through the locking mechanism <NUM>.

In certain embodiments, the receptacle <NUM> is sized and shaped so as to allow the locking mechanism <NUM> to be housed in the dilator hub <NUM>. The locking mechanism <NUM> may be removed from the receptacle <NUM> after interlocking with the guidewire <NUM>.

The locking mechanism <NUM> is removably engaged with at least a portion of the dilator hub <NUM> so that the locking mechanism <NUM> can move in or out of the receptacle <NUM> when the dilator hub <NUM> is slid in a proximal or distal direction, respectively, along the guidewire <NUM>. For example, the locking mechanism <NUM> may be removably held within the receptacle <NUM> via any suitable interaction (e.g., interference, engagement, friction, mechanical coupling, adhesion, etc.). In certain embodiments, once the locking mechanism <NUM> interlocks with the guidewire <NUM> and then abuts a surface of the receptacle <NUM>, further distal movement of the guidewire <NUM> relative to the dilator <NUM> is prevented. In such an embodiment, the locking mechanism <NUM> interlocks with the guidewire <NUM> so that the guidewire <NUM> and locking mechanism <NUM> move in unison during removal of the guidewire <NUM>. In some embodiments, once the locking mechanism <NUM> interlocks with the guidewire <NUM>, further proximal movement of the guidewire <NUM> relative to the dilator <NUM> may be sufficient to overcome the interactive force removably holding the locking mechanism <NUM> within the receptacle <NUM>. For example, the locking mechanism <NUM> may be removed from the receptacle <NUM> after the locking mechanism <NUM> is engaged to the guidewire <NUM> by applying a continuing pulling force to move the guidewire <NUM> in a proximal direction relative to the dilator <NUM>. In certain embodiments, one or more walls such as bottom surface <NUM> of the receptacle <NUM> prevent distal movement of the locking mechanism <NUM> relative to the receptacle <NUM>.

<FIG> is a cross-sectional view of the dilator <NUM> depicted in <FIG> taken along line 4B-4B of <FIG> is an end view of the dilator <NUM> depicted in <FIG> looking in a distal direction.

The dilator hub <NUM> may include locking structures at the proximal region <NUM> and the distal region <NUM> of the dilator <NUM>. Each locking structure may be a luer type or other type of connection. In the illustrated embodiment, the dilator hub <NUM> comprises a luer connection <NUM>. In some embodiments, the luer connection <NUM> (e.g., a male luer slip connector) can be configured to engage to the sheath hub <NUM> (e.g., a female luer slip connector) on the sheath <NUM> illustrated in <FIG>. Additionally, the male-female lure slip connectors on these components can be reversed.

The color of the dilator <NUM> may be selected to enhance the contrast between the blood or other fluid and the dilator <NUM>. During blood flash, for example, blood is observed flowing between the dilator <NUM> and the sheath <NUM> to confirm proper placement in a blood vessel. To increase the visibility of the fluid as the fluid flows between the sheath <NUM> and dilator <NUM>, the sheath <NUM> is preferably manufactured from a clear or transparent material with the dilator <NUM> having a color that contrasts with the color of the fluid. For example, the dilator <NUM> may have a white color to enhance its contrast with red blood. Other colors of dilator <NUM> could be employed depending on the color of the fluid and the degree of contrast desired. Further, only a portion of the dilator <NUM> in the region of the blood flash can have the contrasting color with the remainder having a different color.

In use, the dilator <NUM> expands an opening or passage created by the needle <NUM>. The expanded passage facilitates subsequent introduction of the sheath <NUM>. The needle <NUM> allows the introduction of the guidewire <NUM>, and subsequently the dilator <NUM> and finally the sheath <NUM> into a patient's body.

<FIG> is an end view of a sheath <NUM> that can be used with the access device <NUM> of <FIG>. <FIG> is a side view of the sheath <NUM> depicted in <FIG>. The sheath <NUM> may comprise a sheath body <NUM>, a sheath hub <NUM>, a distal region <NUM>, and a proximal region <NUM>. The sheath body <NUM> may be made partially or completely from clear, translucent, transparent, or semi-opaque material. The sheath body <NUM> can also include one or more radiopaque markers, such as, for example, barium sulfate stripes. In a preferred embodiment, the sheath includes two such radiopaque stripes disposed on diametrically opposite sides of the body <NUM>.

The sheath body <NUM> may be a single piece sheath through which a catheter or other medical article is inserted into the vessel. In such an embodiment, the sheath body <NUM> forms a conduit for insertion of the catheter or other medical article. In addition to providing a conduit, the sheath <NUM> or a portion of the sheath can form a lumen that is in addition to the lumen(s) of the catheter. For example, an equivalent to a triple lumen catheter can be formed by inserting a dual lumen catheter through the sheath body <NUM> with the sheath body <NUM> itself forming a third lumen.

It may be advantageous to remove a portion or the entire sheath body <NUM> depending on the type of catheter or medical article that is to be inserted into the vessel after employing the access device <NUM>. For example, after the catheter or other medical article is inserted into the vessel, a portion of the sheath body <NUM> can be separated or peeled-away and removed. A peel-away sheath can include perforations, serrations, skives, or other structures, or include other materials (e.g., PTFE with bismuth) to allow the physician or healthcare provider to remove easily a portion or the entire sheath body <NUM>.

The sheath hub <NUM> may include a luer slip connection <NUM>. The luer slip connection <NUM> may comprise a locking or attaching structure that mates or engages with a corresponding structure. For example, the luer slip connection <NUM> can be configured to engage with the luer connection <NUM> of the dilator hub <NUM>.

The sheath hub <NUM>, as best seen in <FIG>, preferably is designed so that the luer connection <NUM> of the dilator hub <NUM> can enter the sheath hub <NUM> substantially unobstructed. However, in use, once the sheath hub <NUM> is placed at a desired location over the dilator shaft <NUM>, the physician or healthcare provider can push, pull, or twist the sheath hub <NUM> and possibly disengage or engage the luer slip connection <NUM> with a corresponding connector on another medical article. The luer slip connection <NUM> creates a mechanical fit so that the dilator hub <NUM> and the sheath hub <NUM> are releasably interlocked. The sheath hub <NUM> preferably engages with the corresponding luer connection <NUM> on the dilator hub <NUM>. Preferably, the locked position can be disengaged or engaged by pulling, squeezing, pushing or twisting the dilator hub <NUM> relative to the sheath hub <NUM>.

In additional embodiments, the sheath hub <NUM> may comprise radially extending wings or handle structures to allow for easy release and removal of the sheath body <NUM> from other parts of the access device <NUM>. In some applications, the wings are sized to provide the healthcare provider with leverage for breaking apart the sheath hub <NUM>. For example, the sheath hub <NUM> may comprise a thin membrane connecting the halves of the sheath hub <NUM>. The membrane is sized to keep the halves of the sheath hub <NUM> together until the healthcare provider decides to remove the sheath hub <NUM> from the access device. The healthcare provider manipulates the wings to break the membrane and separate the sheath hub <NUM> into removable halves.

<FIG> is a side cross-sectional view of the access device <NUM> depicted in <FIG> after the access device <NUM> has been threaded over the guidewire <NUM>. Thus, in the illustrated embodiment, the dilator <NUM> includes the dilator shaft <NUM> that extends distally from the dilator hub <NUM>, and the sheath <NUM> includes the sheath body <NUM> that extends distally from the sheath hub <NUM>. In certain embodiments, the guidewire <NUM> includes a guidewire hub or cap (not shown). In the illustrated embodiment, the dilator <NUM> and the sheath <NUM> are releasably interlocked at a proximal end of the access device <NUM>. In some embodiments, the releasable interlock between the dilator <NUM> and the sheath <NUM> is a linear interlock where the sheath <NUM> is locked to the dilator <NUM>. The relative positioning of the terminal ends of the dilator <NUM> and the sheath <NUM> are shown in <FIG>. For example, the terminal end of the dilator body <NUM> extends beyond the terminal end of the sheath <NUM>.

<FIG> are various views of a proximal region <NUM> of the guidewire <NUM> depicted in <FIG> showing a guidewire stop 92A, 92B configured to be used by the locking mechanism <NUM> to secure to the guidewire <NUM>. In certain embodiments, the guidewire stop 92A, 92B is one or more features of the guidewire <NUM> which allow the locking mechanism <NUM> to engage the guidewire <NUM>. In the embodiment illustrated in <FIG>, the guidewire stop 92A is in the form of an annular groove defined by one or more ridges (e.g., two ridges). The groove may be sized and configured to engage with the corresponding locking mechanism <NUM>, as described herein. While the guidewire stop 92A is illustrated as a groove, it will be understood by one having skill in the art that the guidewire stop may comprise any shape or size suitable to engage the locking mechanism <NUM>. For example, as illustrated in <FIG>, the guidewire stop 92B may comprise an outward protrusion configured to inhibit further distal movement of the guidewire <NUM> relative to the locking mechanism <NUM> once the guidewire stop 92B abuts and/or engages the locking mechanism30. The guidewire stop 92B may function in a similar manner as the guidewire stop 92A. In some instances, the guidewire stop 92B may comprise one or more outward protrusions (e.g. cams) protruding from on one or more sides of the guidewire <NUM>. The one or more cams may be sized and configured to separate the opposing clips <NUM> (as described herein and shown in <FIG>) of the locking mechanism <NUM> as the one or more cams pass through the opposing clips <NUM> in a proximal direction relative to the locking mechanism <NUM>. After the one or more cams pass through the opposing clips <NUM>, the opposing clips <NUM> may close behind the one or more cams to prevent distal movement of the one or more cams relative to the opposing clips <NUM>. Additionally, while the guidewire stop 92A, 92B is illustrated as residing on the proximal region <NUM> of the guidewire <NUM>, it will be understood by one having skill in the art that the guidewire stop 92A, 92B may be placed at any location along the guidewire <NUM>. In certain other embodiments, the guidewire stop is in the form of a notch, taper, barb, adhesive, magnet, or other feature.

In some instances, the guidewire stop 92A, 92B can be formed by varying the width of the guidewire <NUM>. For example, the guidewire 92B may comprise a portion of the guidewire <NUM> that comprises an increased width relative to the remainder of the guidewire <NUM>. The increased width portion of the guidewire stop 92B may be followed by a guidewire <NUM> section of reduced width that is located both proximal and distal to the guidewire stop 92B. The increased width of the guidewire stop 92B may be sized and configured to permit the locking mechanism <NUM> to engage the guidewire stop 92B, while also being of a sufficient width to inhibit the guidewire stop 92B from passing through the opening <NUM> of the locking mechanism <NUM>, described herein. The increased width of the guidewire stop 92B can be configured to engage the locking mechanism <NUM>, while also permitting the guidewire stop 92B to pass through the interior bore <NUM> of the needle <NUM>. For example, an outer width of the guidewire stop 92B may be smaller than an interior diameter of the interior bore <NUM> of the needle <NUM>. The increased width of the guidewire stop 92B may be formed by any suitable means. For example, the guidewire stop 92B may comprise an annular flange located along the guidewire <NUM>. By way of another example, the guidewire stop 92B may be formed by stamping and/or compressing a portion of the guidewire <NUM> to form a guidewire stop <NUM> that comprises a pinched surface with an outwardly protruding increased width along the guidewire <NUM>.

The guidewire stop 92A, 92B is preferably disposed in the proximal region <NUM> of the guidewire <NUM> and is configured to engage with the locking mechanism <NUM> at least when the dilator <NUM> is threaded over the guidewire <NUM>. Until the guidewire stop 92A, 92B interlocks with the locking mechanism <NUM> and causes the locking mechanism <NUM> and/or the guidewire stop 92A, 92B to abut against the wall <NUM>, the healthcare provider can freely manipulate the guidewire <NUM> within the dilator <NUM>. However, after the guidewire stop 92A, 92B interlocks and then contacts the wall <NUM>, the healthcare provider is prevented from extending the guidewire <NUM> further in a distal direction relative to the dilator <NUM>.

In certain embodiments, as the guidewire <NUM> is initially threaded through the dilator hub <NUM>, the locking mechanism <NUM> closes about the outer surface of the guidewire <NUM> so as to pinch the guidewire <NUM>. The pinching force, in some instances, may not be sufficient to engage with the guidewire <NUM>. In certain embodiments, the bite force of the locking mechanism <NUM> on the guidewire <NUM> is insufficient to prevent movement of the guidewire <NUM> relative to the locking mechanism <NUM>. The bite force of the locking mechanism <NUM> on the guidewire <NUM> may still permit movement of the guidewire <NUM> relative to the locking mechanism <NUM> until the locking mechanism <NUM> interlocks or engages with the guidewire stop 92A, 92B. For example, the locking mechanism <NUM> may not sufficiently resist passage of the guidewire <NUM> through the locking mechanism <NUM> before the locking mechanism <NUM> engages the guidewire stop 92A, 92B. Once the locking mechanism <NUM> engages with the guidewire stop 92A, 92B, the locking mechanism <NUM> inhibits at least further distal movement of the guidewire <NUM> relative to the locking mechanism <NUM>.

<FIG> is a perspective view of the locking mechanism <NUM> from <FIG> removed from the dilator <NUM>. <FIG> is an opposite end perspective view of the locking mechanism <NUM> from <FIG>. As discussed herein, the dilator hub <NUM> comprises the locking mechanism <NUM>. In certain embodiments, the locking mechanism <NUM> is disposed in the sheath <NUM> or other medical article. The locking mechanism <NUM> may be configured to lock or secure to the guidewire <NUM>. As shown in <FIG>, the locking mechanism <NUM> comprises a guidewire lock <NUM> and an opening <NUM>. The guidewire lock <NUM> can comprise one or more engaging mechanisms such as a pair of opposing clips, teeth, tabs, or opening, although other types of locking mechanisms comprising tabs and/or slots can also be used.

In the illustrated embodiment, the guidewire lock <NUM> is configured as a pair of opposing clips <NUM>. The locking mechanism <NUM> is generally V-shaped and is configured to be biased towards a closed condition, while still permitting the locking mechanism <NUM> to slide over the guidewire <NUM> when the guidewire <NUM> is advanced through the V-shaped locking mechanism <NUM> and then to spring towards the guidewire <NUM> and into the guidewire stop 92A, 92B.

<FIG> is a view similar to <FIG> except the guidewire lock <NUM> is open or in an unlocked state, allowing the guidewire <NUM> to pass through the locking mechanism <NUM> as the dilator <NUM> and the sheath <NUM> are threaded over the guidewire <NUM>. The guidewire lock <NUM> can be biased towards a closed configuration as illustrated in <FIG>. The degree of bias of the guidewire lock <NUM> towards the closed condition is selected so that the guidewire <NUM> can slide through the guidewire lock <NUM> when the guidewire lock <NUM> is not in contact or engaged with the guidewire stop 92A, 92B. The guidewire lock <NUM> is in a locked state when the guidewire lock <NUM> is engaged with the guidewire stop 92A, 92B (as illustrated in <FIG>).

<FIG> is a view similar to <FIG> but taken from the opposite end of the locking mechanism <NUM> and with the dilator <NUM> and the sheath <NUM> further threaded over the guidewire <NUM> until the locking mechanism <NUM> interlocks with the guidewire stop 92A, 92B on the guidewire <NUM>. <FIG> is an enlarged partial cross-section view from <FIG> of the locking mechanism <NUM> interlocked with the guidewire stop 92A on the guidewire <NUM>. By way of another example, <FIG> is an enlarged partial cross-section view from <FIG> of the locking mechanism <NUM> interlocked with the guidewire stop 92B on the guidewire <NUM>. In the illustrated embodiments, the locking mechanism <NUM> has slid in the distal direction relative to the guidewire <NUM> until the locking mechanism <NUM> interlocks with the guidewire stop 92A, 92B on the guidewire <NUM>. The clips <NUM> of the guidewire lock <NUM> can engage a lipped and/or compressed surface such as the guidewire stop 92A, 92B shown in <FIG>. Once engaged, the guidewire lock <NUM> inhibits the guidewire stop 92A, 92B from undesired slipping or releasing relative to the locking mechanism <NUM>. The guidewire <NUM> can essentially carry the locking mechanism <NUM> and move in unison with the locking mechanism <NUM>. In certain embodiments, the guidewire lock <NUM> is hinged to provide a bias towards the center of the dilator hub <NUM>. The bias may prevent the secured part of the guidewire <NUM> from slipping or disengaging from the guidewire lock <NUM>.

The interlocking structure illustrated in <FIG> is but one example of the types of cooperating structure that can be included to interconnect or interlock the locking mechanism <NUM> with the guidewire <NUM> and/or the dilator <NUM>. The interlocking structure, in some embodiments, does not engage with the guidewire <NUM> until the dilator <NUM> is sufficiently threaded over the guidewire <NUM> to allow the interlocking structure to contact the guidewire lock <NUM>. In this way, the interlocking structure does not inhibit use or appreciably increase contact friction when the healthcare provider is manipulating the guidewire <NUM> until after the guidewire lock <NUM> contacts the guidewire stop 92A, 92B.

<FIG> are various views of the locking mechanism <NUM> and dilator hub <NUM>, according to some embodiments. At least a portion of the locking mechanism <NUM> (e.g., the opposing clips 80A, 80B shown in <FIG>), in some instances, may be engaged with a portion of the dilator hub <NUM> to initially maintain the locking mechanism <NUM> in the open state. As shown in <FIG>, respectively, the locking mechanism <NUM> may have a first open state positioned on the dilator hub <NUM> and a second closed state positioned on and/or engaged with the guidewire <NUM>.

As illustrated in <FIG>, when the locking mechanism <NUM> is in the open state, the locking mechanism <NUM> may be placed along a portion of the dilator hub <NUM>. The locking mechanism <NUM> can be clamped, preformed, or otherwise positioned over or around at least a portion of the dilator hub <NUM> to temporarily maintain the locking mechanism <NUM> in the open state and inhibit the locking mechanism <NUM> from entering the closed state. An interior surface of the dilator hub <NUM> may comprise a ledge, groove, ride, or any suitable protrusion configured to engage one or more of the opposing clips 80A, 80B to hold the locking mechanism <NUM> in the open state before interaction with the guidewire stop.

The protrusion can be sized and configured to extend along any portion and/or length of the receptacle <NUM> of the dilator hub <NUM>. For example, the protrusion can be configured to be positioned within the receptacle <NUM> on a distal end or proximal end of the dilator hub <NUM>. For example, the dilator hub <NUM> may include one or more ledges 76A, 76B configured to engage a corresponding clip 80A, 80B. The protrusion can be configured such that a first portion of the locking mechanism <NUM> (e.g., a first clip 80A) is positioned along a corresponding portion of the protrusion (e.g., a first ledge 76A), and a second portion of the locking mechanism <NUM> (e.g., a second clip 80B) is positioned along a corresponding second portion of the protrusion (e.g., a second ledge 76B) to maintain the locking mechanism <NUM> in the open state. The locking mechanism <NUM> can be configured to interlock, engage or adhere to the protrusion when initially positioned within the receptacle <NUM>. In some embodiments, the first portion and the second portion of the locking mechanism <NUM> (e.g., clips 80A, 80B) can adhere at least to the protrusion comprising an adhesive. In some embodiments, the adhesive can extend along an entire inner perimeter of the protrusion. The protrusion can be made of a single unitary body (e.g., an annular ridge) within the dilator hub <NUM> to that is configured to allow the opposing clips 80A. 80B to position themselves over and/or around the one or more ledges 76A, 76B to temporarily maintain the locking mechanism <NUM> in the open state.

The locking mechanism <NUM> can comprise an opening <NUM> (as shown in <FIG>) that is sized and configured to selectively permit at least a portion of the guidewire <NUM> to pass through. The opening <NUM> can be chamfered to facilitate insertion of the guidewire proximal end through opening <NUM>. An inner diameter of the opening <NUM>, as described herein, can be sufficiently large to permit a portion of the guidewire <NUM> to reside within and/or pass through the opening <NUM>. However, in some embodiments, the inner diameter of the opening <NUM> is not large enough to permit at least another portion of the guidewire <NUM> to pass through the opening <NUM> (e.g., the guidewire stop 92B). As such, the guidewire stop 92B may generally be too large to fit through the opening <NUM> and further proximal movement of the guidewire <NUM> relative to the dilator hub <NUM> will cause the locking mechanism <NUM> to transition into the closed state. For example, the guidewire stop 92B can abut against the locking mechanism <NUM> and cause the locking mechanism <NUM> to move in a proximal direction relative to the dilator hub <NUM> and, consequently, detach the one or more clips 80A, 80B from the protrusion (e.g., one or more ledges 76A, 76B) of the dilator hub <NUM>, as described with reference to <FIG>.

In some instances, when the locking mechanism <NUM> transitions from the open state to the closed state, the locking mechanism <NUM> can be positioned around a portion of the guidewire <NUM> such that the locking mechanism <NUM> prevents the guidewire <NUM> from moving distally beyond the dilator hub <NUM>. As the guidewire <NUM> is moved in a proximal direction relative to the dilator hub <NUM> (shown in <FIG>), the guidewire stop 92B can abut against and/or engage the locking mechanism <NUM>. Further distal movement of the guidewire stop 92B relative to the dilator hub <NUM> can cause the guidewire stop 92B to detach the locking mechanism <NUM> from the protrusion of the dilator hub <NUM>. Removal of the locking mechanism <NUM> from the protrusion may cause the locking mechanism <NUM> to transition to the closed state and engage at least a portion of the guidewire <NUM> (shown in <FIG>). In some instances, the first clip 80A and/or the second clip 80B of the locking mechanism <NUM>, once removed from the protrusion of the dilator hub <NUM>, may engage the guidewire <NUM> to enclose at least a portion of the guidewire <NUM>. The locking mechanism <NUM> can enclose the guidewire <NUM> to inhibit access of the engaged portion of the guidewire <NUM> in a distal direction beyond the dilator hub <NUM>, as described herein. The locking mechanism <NUM>, as described herein, can be biased towards the close state so that when in the locking mechanism <NUM> is disengaged with the protrusion, the locking mechanism <NUM> automatically transitions towards the closed state (as illustrated in <FIG>).

Other types of locking mechanisms can also be used for this purpose. For example, but without limitation, an annular bead can be located within the dilator hub <NUM> and biased towards a closed configuration. Once the guidewire stop 92A, 92B contacts the guidewire lock <NUM>, the bead snaps closed about guidewire <NUM>. In some instances, the dilator hub <NUM> can include one or more annular grooves defined within the receptacle <NUM>. When the bead reaches the annular groove the bead and guidewire <NUM> are prevented from further distal movement.

In some embodiments, the locking mechanism <NUM> may comprise one or more finger or tang or cam elements defining the guidewire lock <NUM> or opening configured to permit the guidewire <NUM> to pass through the locking mechanism <NUM>. The one or more finger elements can project from a distal end of the locking mechanism <NUM> toward a proximal end of the locking mechanism <NUM>. The one or more finger elements may permit the guidewire stop 92A, 92B to pass through the guidewire lock <NUM> or the opening in a proximal direction but inhibit to passage of the guidewire stop 92A, 92B through the guidewire lock <NUM> or the opening in a distal direction. The guidewire stop 92A, 92B can slide through the opening in a proximal direction through the finger elements. As the guidewire stop 92A, 92B passes through, the finger elements can lock into a biased closed position between the guidewire lock <NUM> or the opening and the guidewire stop 92A, 92B. This inhibits and/or substantially irreversibly prevents axial movement of the guidewire stop 92A, 92B at least in the distal direction once the guidewire stop 92A, 92B passes through the opening.

As with the illustrated embodiment, the degree of bias of the locking mechanism <NUM> towards the closed condition is selected so that the guidewire <NUM> can slide through the locking mechanism 30when the locking mechanism 30is not in contact with the guidewire stop <NUM>. Once the locking mechanism 30contacts and locks to the guidewire stop <NUM>, the healthcare provider can generally simultaneously withdraw the dilator <NUM> and the guidewire <NUM> from the sheath <NUM> without risking the embolization of the guidewire <NUM>. The engagement of the locking mechanism <NUM> with the guidewire <NUM> and/or the dilator <NUM> can occur through simple axial movement of the guidewire <NUM> relative to the dilator hub <NUM>, as understood from the embodiments described above.

<FIG> is a cross-sectional view of the needle <NUM> illustrated in <FIG> penetrating a body <NUM>. <FIG> is an enlarged partial cross-sectional view from <FIG> of a distal end of the needle <NUM>. In <FIG>, the needle <NUM> has penetrated the vasculature. <FIG> is an enlarged partial cross-sectional view from <FIG> of a distal end of the needle <NUM>. In use, the bevel tip <NUM> enters the blood vessel <NUM>.

<FIG> is a cross-sectional view similar to <FIG> where a guide wire <NUM> has been fed through the needle <NUM> and into the blood vessel <NUM> of the patient. Once the physician or healthcare provider has located the needle <NUM> within the target blood vessel <NUM>, the physician or healthcare provider feeds the guidewire <NUM> into the vasculature. The needle <NUM> is held still while the guidewire <NUM> is fed through the needle <NUM> and into the patient. During the insertion procedure, the guidewire <NUM> passes through the interior bore <NUM> of the needle <NUM>.

A guide wire advancer as known in the art may be employed when feeding the guidewire <NUM> through the needle <NUM>. For example, if the guidewire <NUM> has a curved or J tip, an advancer may be employed to straighten the tip facilitating feeding of the guidewire <NUM> into the interior bore <NUM> of the needle <NUM>. <FIG> is a cross-sectional view similar to <FIG> except the guidewire <NUM> has been extended further into the vasculature of the patient.

<FIG> is a cross-sectional view similar to <FIG> where the needle <NUM> has been removed and the dilator <NUM> and the sheath <NUM> have been slid along the exterior portion of the guidewire <NUM> until the locking mechanism <NUM> in the dilator <NUM> interlocks with the guidewire stop 92A, 92B. <FIG> is an enlarged partial cross- sectional view from <FIG>. The locking mechanism <NUM> within the receptacle <NUM> of the dilator <NUM> has effectively slid in the distal direction relative to the guidewire <NUM> until the locking mechanism <NUM> interlocks with the guidewire stop <NUM> on the guidewire <NUM>. The clips <NUM> of the guidewire lock <NUM> can engage a lipped surface such as the guidewire stop 92A, 92B shown in <FIG>. Once engaged, the guidewire lock <NUM> prevents the locked part of the guidewire <NUM> from undesired slipping or releasing relative to the locking mechanism <NUM>. The guidewire <NUM> can essentially carry the locking mechanism <NUM> and move in unison with the locking mechanism <NUM>. In certain embodiments, the guidewire lock <NUM> is hinged to provide a bias towards the center of the dilator hub <NUM><NUM>. The bias can prevent the secured part of the guidewire <NUM> from slipping or disengaging from the guidewire lock <NUM>.

In some embodiments, the orientation of the locking mechanism <NUM> within the dilator hub <NUM> may be reversed. For example, <FIG> is an enlarged partial cross- sectional view similar to <FIG>, except where the opposing clips <NUM> of the locking mechanism <NUM> (as described herein) are located in a proximal direction from the opening <NUM> of the locking mechanism <NUM>. While in a reversed orientation (shown in <FIG>), the locking mechanism <NUM> may function in the same manner as described herein; however, the guidewire <NUM> and the guidewire stop 92A, 92B may pass through the opening <NUM> prior to passing through or engaging the opposing clips <NUM>, respectively. In such an embodiment, the guidewire stop 92A, 92B and the opening <NUM> may be sized and configured to permit the guidewire stop 92A, 92B to pass through the opening <NUM>. To further facilitate insertion of the guidewire proximal end through the opening <NUM>, the distal side of opening <NUM> can be chamfered.

<FIG> is a cross-sectional view similar to <FIG> where the dilator <NUM> and sheath <NUM> have been slid further along the exterior portion of the guidewire <NUM> and into the patient's vasculature causing the dilator <NUM> to be spaced from the locking mechanism <NUM>. During threading of the sheath <NUM> and the dilator <NUM> over the guidewire <NUM> and into the blood vessel <NUM>, the guidewire <NUM> freely slides through the locking mechanism <NUM> until the guidewire lock <NUM> interlocks with the guidewire stop 92A, 92B. Once interlocked, the guidewire <NUM> and the locking mechanism <NUM> can move in unison. In this configuration, the guidewire <NUM> is prevented from exiting a distal end of the dilator <NUM> in a distal direction and being lost in the patient.

<FIG> is a cross-sectional view similar to <FIG> where the guidewire <NUM> and interlocked locking mechanism <NUM> have been withdrawn from the dilator <NUM> and the sheath <NUM>. In certain embodiments, the healthcare provider can instead withdraw the dilator <NUM> until the locking mechanism <NUM> contacts or interlocks with the dilator <NUM>. Prior to removing the guidewire <NUM>, the locking mechanism <NUM> can interlock with the dilator <NUM> by abutting the wall <NUM>. Accordingly, further withdrawal of the dilator <NUM> will also withdraw the locking mechanism <NUM> and the guidewire <NUM> from the sheath <NUM>.

<FIG> is a cross-sectional view similar to <FIG> where the dilator <NUM> has been removed from the patient and the sheath <NUM>. The sheath <NUM> is left properly inserted within the blood vessel <NUM>. The dilator <NUM> may be removed after or in concert with removal of the guidewire <NUM>.

<FIG> is a cross-sectional view similar to <FIG> where a catheter <NUM> is aligned with the sheath <NUM> for insertion into the patient's vasculature. <FIG> is a cross-sectional view similar to <FIG> where the catheter <NUM> has been inserted through the sheath <NUM> and into the patient's vasculature, specifically the targeted blood vessel <NUM>.

<FIG> is a cross-sectional view similar to <FIG> where two portions of the sheath <NUM> are being peeled away from each other to remove the sheath <NUM> from encircling the catheter <NUM>. The sheath <NUM> is splittable along one or more split lines. A splittable sheath <NUM> provides the advantage of allowing a portion of or the entire sheath body <NUM> to be removed depending on the type of catheter or medical article that is to be inserted into the vessel after employing the access device <NUM>. For example, after the catheter <NUM> is inserted into the blood vessel <NUM>, a portion of the sheath body <NUM> is separated or peeled- away and removed to reduce clutter at the access site. The peel-away sheath <NUM> can be first slid in a proximal direction along the catheter <NUM> until the sheath <NUM> is removed from the patient and then split apart. Alternatively, the sheath <NUM> can be initially split prior to the entire sheath <NUM> being removed from the patient. After the remainder of the sheath <NUM> is removed from the patient, the physician or healthcare provided can continue splitting the sheath <NUM>. Of course, the sheath <NUM> could be split in concert with its removal from the patient as is illustrated in <FIG>. In certain embodiments, the sheath <NUM> is not splittable.

<FIG> are various views of a locking mechanism to engage the guidewire <NUM>, according to some embodiments. In particular, <FIG> is a front view of an embodiment of a locking mechanism <NUM>, and <FIG> are rear and side cross-sectional views of the locking mechanism <NUM>, respectively. <FIG> are side cross-sectional views of an exemplary non-claimed method of engaging the locking mechanism <NUM> with a guidewire <NUM> including a guidewire stop 92B. Unless otherwise noted, the locking mechanism <NUM> as shown in <FIG> may include components that are the same as or generally similar to the components in the remaining figures discussed herein, as identified by similar reference numerals. It will be understood that the features described with reference to locking mechanism <NUM> shown in <FIG> can be used with any of the embodiments described and/or contemplated herein. It will also be understood that any feature, structure, material, step, or component of any embodiment described and/or illustrated herein can be used with or instead of any other feature, structure, material, step, or component of any embodiment of locking mechanism <NUM> shown in <FIG>.

As shown in the illustrated embodiment, the locking mechanism <NUM> may comprise a sphere including an external wall <NUM>. The locking mechanism <NUM>, as illustrated, may be hollow in order to receive at least a portion of the guidewire <NUM> within an internal cavity <NUM> of the locking mechanism. In some embodiments, the locking mechanism <NUM> may comprise one or more openings. A user may utilize the one or more openings to permit a guidewire <NUM> to pass through the locking mechanism <NUM> and engage a guidewire stop 92B within the internal cavity <NUM> to prevent unintended removal of the locking mechanism <NUM> from the guidewire <NUM>. In some embodiments, the locking mechanism <NUM> can comprise an elastomeric material and/or flexible structure capable of slight deformation as the guidewire stop 92B passes through the one or more openings of the locking mechanism <NUM>.

A first opening may function as a guidewire lock <NUM>, as described herein. A second opening <NUM> may allow a portion of the guidewire <NUM> proximal to the guidewire stop 92B to pass through and/or exit the internal cavity <NUM> of the locking mechanism <NUM>, while still maintaining a portion of the guidewire <NUM> (e.g., the guidewire stop 92B) within the internal cavity <NUM>. As shown in <FIG>, the openings may be located on opposite sides of the external wall <NUM>.

In some embodiments, the first opening or locking element <NUM> may be located at a distal end of the locking mechanism <NUM>. The opening of the locking element <NUM> may not comprise a constant diameter along the entire length of the external wall <NUM> of the locking mechanism <NUM> (as shown in <FIG>). For example, the locking element <NUM> may include an external opening <NUM> and an internal opening <NUM> of varying diameters that extend through the external wall <NUM>. In some embodiments, a diameter of the external opening <NUM> of the locking element <NUM> can be larger than a diameter of the internal opening <NUM> of the locking element <NUM>. As such, the locking element <NUM> may taper towards the internal opening <NUM>. The tapering may advantageously permit the guidewire stop 92B to pass through the locking element <NUM> only in a proximal direction and into the internal cavity <NUM>, while inhibiting the guidewire stop 92B from passing through the locking element <NUM> in a distal direction once the guidewire stop d92B has been inserted into the internal cavity <NUM>. The locking element <NUM> can comprise any suitable shape and configuration capable of receiving and/or engaging the guidewire stop 92B. For example, as shown in <FIG>, the locking element <NUM> can comprise a generally conical shape, although it will be appreciated that the locking element <NUM> can comprise any suitable wall structure (e.g., straight and/or curved) and have any suitable shape (e.g., cylindrical, tapered).

As illustrated in <FIG>, the diameter of the external opening <NUM> may be larger than the guidewire <NUM> (e.g., including the guidewire stop 92B), but the diameter of the internal opening <NUM> may be smaller than at least the guidewire stop 92B. In some instances, the diameter of the internal opening <NUM> can be smaller than the outer width or diameter of the guidewire stop 92B, but sufficiently large so that the external wall <NUM> defining the internal opening <NUM> can temporarily resiliently or flexibly increase in size to permit the guidewire stop 92B to pass through the internal opening <NUM> in a proximal direction and into the internal cavity <NUM>, while inhibiting removal of the guidewire stop 92B in a distal direction from the internal cavity <NUM> once inserted.

<FIG> show that, in some embodiments, both the second opening <NUM> and the internal opening <NUM> can each comprise an internal diameter smaller than an external width of an outer surface of the guidewire stop 92B to prevent the unintended removal of the guidewire stop 92B from the internal cavity <NUM> in a distal and/or proximal direction. Accordingly, the second opening <NUM> and the internal opening <NUM> may be sized to permit only portions of the guidewire <NUM> that are located distal and/or proximal to the guidewire stop 92B to extend outside of the internal cavity <NUM>, while the guidewire stop 92B remains contained inside of the internal cavity <NUM>.

The locking element <NUM> can comprise any suitable shape and/or configuration capable of permitting the guidewire stop 92B to access the internal cavity <NUM> of the locking mechanism <NUM>, while resisting removal of the guidewire stop 92B from within the internal cavity <NUM>. The external wall <NUM> may comprise any material suitable to permit engagement with the guidewire <NUM> without causing the locking mechanism <NUM> to tear or irreversibly stretch or otherwise be damaged upon passage of the guidewire stop 92B through the internal opening <NUM>. To prevent accidental disengagement of the locking mechanism <NUM> from the guidewire stop 92B, in some embodiments, the locking mechanism <NUM> can comprise a semi-rigid or resilient or elastomeric material capable of slight deformation when a force is applied. As the guidewire stop 92B is inserted into the internal cavity <NUM>, the internal opening <NUM> can be configured to deform radially outward or in an opening direction that is generally perpendicular to the longitudinal axis of the guidewire stop 92B. In some embodiments, the internal opening <NUM> can be configured to rebound radially inward in a closing direction, generally opposite from the opening direction, after the guidewire stop 92B is inserted into the internal cavity <NUM> (as shown in <FIG>). This may advantageously allow the internal opening <NUM> of the locking element <NUM> to temporarily and/or permanently retain the guidewire stop 92B within the internal cavity <NUM>.

<FIG> are various views of another locking mechanism to engage the guidewire <NUM>, according to some embodiments. In particular, <FIG> is a front view of an embodiment of a locking mechanism <NUM>, and <FIG> is a side cross- sectional view of the locking mechanism <NUM>. <FIG> are side cross- sectional views of an exemplary non-claimed method of engaging the locking mechanism <NUM> with a guidewire <NUM> including a guidewire stop 92B. Unless otherwise noted, the locking mechanism <NUM> as shown in <FIG> may include components that are the same as or generally similar to the components in the remaining figures discussed herein, as identified by similar reference numerals. It will be understood that the features described with reference to locking mechanism <NUM> shown in <FIG> can be used with any of the embodiments described and/or contemplated herein. It will also be understood that any feature, structure, material, step, or component of any embodiment described and/or illustrated herein can be used with or instead of any other feature, structure, material, step, or component of any embodiment of locking mechanism <NUM> shown in <FIG>.

The locking mechanism <NUM>, as illustrated, can comprise a sheath or disc that is configured to interact with at least a portion of the guidewire <NUM> (e.g., the guidewire stop 92B), as shown in <FIG>. The locking mechanism <NUM>, as described herein, can be folded, wrapped, or otherwise positioned over or around the guidewire <NUM> to enclose at least a portion of the guidewire stop 92B, or otherwise interact with the guidewire stop 92B, to inhibit the locking mechanism <NUM> and the guidewire stop 92A from moving in a distal direction beyond the dilator hub <NUM> (e.g., into the dilator shaft).

The locking mechanism <NUM> can be made of a single unitary body that can fold, be folded, be wrapped, or otherwise automatically position itself over or around, be positioned over or around, or be folded over or around the dilator hub <NUM> and/or the guidewire <NUM> to inhibit unintentional distal movement of the guidewire <NUM> relative to the dilator hub <NUM>. As shown in <FIG>, respectively, the locking mechanism <NUM> may have a first configuration positioned on the proximal portion <NUM> of the dilator hub <NUM> and a second configuration positioned on and engaged with the guidewire <NUM>.

As illustrated in <FIG>, when the locking mechanism is in the first configuration, the locking mechanism <NUM> may be placed along a proximal portion <NUM> of the dilator hub <NUM>. The locking mechanism <NUM> can be sized and configured to extend along and enclose any portion and/or length of the receptacle <NUM> of the dilator hub <NUM>. For example, the locking mechanism <NUM> can be configured to be positioned over and enclose the receptacle <NUM> on a proximal end of the proximal portion <NUM> of the dilator hub <NUM>. The locking mechanism <NUM> can be configured such that a first portion 244a of the locking mechanism is positioned along a corresponding first portion of the dilator hub <NUM>, and a second portion 244b of the locking mechanism <NUM> is positioned along a corresponding second portion of the dilator hub <NUM> to substantially enclose the receptacle <NUM>. The locking mechanism <NUM> can be configured to adhere to the dilator hub <NUM> when positioned. In some embodiments, the first portion 244a and the second portion 244b of the locking mechanism <NUM> can adhere at least to the dilator hub <NUM> along an engagement portion comprising an adhesive. In some embodiments, the engagement portion can extend along an entire outer perimeter of the locking mechanism <NUM>.

The locking mechanism <NUM> can comprise an opening <NUM> that is sized and configured to selectively permit at least a portion of the guidewire <NUM> to pass through. An inner diameter of the opening <NUM>, as described herein, can be sufficiently large to permit a portion of the guidewire <NUM> to reside within and/or pass through the opening <NUM>. However, the inner diameter of the opening <NUM> is not large enough to permit at least another portion of the guidewire <NUM> to pass through the opening <NUM> (e.g., the guidewire stop 92B). As such, the guidewire stop 92B may generally be too large to fit through the opening <NUM> and further proximal movement of the guidewire <NUM> relative to the dilator hub <NUM> will remove the locking mechanism <NUM> from the dilator hub <NUM> in a proximal direction to detach the locking mechanism <NUM> from the dilator hub <NUM>, as described with reference to <FIG>.

In some instances, when the locking mechanism <NUM> is in the second configuration, the locking mechanism <NUM> can be positioned around the guidewire stop 92B such that the locking mechanism <NUM> prevents the guidewire stop 92B from moving distally beyond the dilator hub <NUM>. As the guidewire <NUM> is moved in a proximal direction relative to the dilator hub <NUM> (shown in <FIG>), the guidewire stop 92B can abut against and/or engage the locking mechanism <NUM>. Further distal movement of the guidewire stop 92B relative to the dilator hub <NUM> can cause the guidewire stop 92B to peel off and/or detach the locking mechanism <NUM> from the dilator hub <NUM>. Removal of the locking mechanism <NUM> from the dilator hub <NUM> may cause the locking mechanism <NUM> to become folded over the guidewire stop 92B (shown in <FIG>). In some instances, the first portion 244a and/or the second portion 244b of the locking mechanism <NUM>, once removed from the dilator hub <NUM>, may adhere to and/or engage the guidewire <NUM> to enclose at least a portion of the guidewire stop 92B. The locking mechanism <NUM> can enclose the guidewire stop 92B to inhibit access of the guidewire stop 92B in a distal direction beyond the dilator hub <NUM>, as described herein. The locking mechanism <NUM> can be folded in the lateral direction and/or the longitudinal direction to cover the guidewire stop 92B.

In some embodiments, the locking mechanism <NUM>, when in the second configuration (as illustrated in <FIG>), can be formed by folding, wrapping, enveloping, or crimping the locking mechanism <NUM> around or over at least a portion of the guidewire <NUM> to cover at least the guidewire stop 92B. The first portion 244a and/or the second portion 244b can be configured to engage and/or adhere to a portion of the locking mechanism <NUM> itself and/or any portion of the guidewire <NUM>.

The locking mechanism <NUM> can be circular (as illustrated), square, rectangular, oval, or any other suitable size and/or shape to enclose and/or form a radial extension from a portion of a guidewire. The locking mechanism <NUM> can initially be substantially flat for ease of manufacturing and assembly. The locking mechanism <NUM> can be made of a variety of flexible or semi-rigid materials such as polyester film or sheet, plastic sheet or film, or PET (polyethylene terephthalate). For example, the locking mechanism <NUM> can comprise Mylar® polyester film. The locking mechanism <NUM> can be formed by adhering a plastic sheet or film over the dilator hub <NUM>, as described herein.

As shown in the illustrated embodiment, the locking mechanism <NUM> may comprise a cylinder including an external wall <NUM>. The locking mechanism <NUM>, as illustrated, may be substantially hollow in order to receive at least a portion of the guidewire <NUM> within an internal cavity <NUM> of the locking mechanism <NUM>. In some embodiments, the locking mechanism <NUM> may comprise one or more openings. A user may utilize the one or more openings to permit a guidewire <NUM> to pass through at least a portion of the locking mechanism <NUM>. A first opening <NUM> may permit at least a portion of the guidewire <NUM> to enter the internal cavity <NUM> of the locking mechanism <NUM>. A second opening <NUM> may allow a portion of the guidewire <NUM> proximal to the guidewire stop 92B to pass through and/or exit the internal cavity <NUM> of the locking mechanism <NUM>, while still maintaining a portion of the guidewire <NUM> (e.g., the guidewire stop 92B) within the internal cavity <NUM>. As shown in <FIG>, the openings may be located on opposite sides of the external wall <NUM>.

The locking mechanism <NUM> can comprise a locking element <NUM> to engage a guidewire stop 92B within the internal cavity <NUM> and to prevent unintended removal of the locking mechanism <NUM> from the guidewire <NUM>. In some embodiments, the locking element <NUM> can comprise an adhesive, elastomeric, and/or gel-like material (e.g., silicone or acrylic gel) capable of interacting and/or interlocking with at least a portion of the guidewire <NUM> (e.g., the guidewire stop 92B), as shown in <FIG>. The locking mechanism <NUM>, as described herein, can adhere, attach, engage, or otherwise interact with (e.g., mold around or envelop) at least a portion of the guidewire stop 92B to inhibit the locking the locking mechanism <NUM> and the guidewire stop 92B from moving in a distal direction beyond the dilator hub <NUM> (e.g., into the dilator shaft).

The locking element <NUM> can be made of a single unitary body that can be positioned within the internal cavity <NUM> of the locking mechanism <NUM> to inhibit unintentional distal movement of the guidewire <NUM> relative to the dilator hub <NUM>. In some embodiments, the locking element <NUM> may be located at least along a proximal end of the internal cavity <NUM>. As shown in the illustrated embodiment, the locking element <NUM> may comprise a generally cylindrical shape that may be substantially hollow in order to receive at least a portion of the guidewire <NUM> within the locking element <NUM>. In some embodiments, the locking element <NUM> may comprise one or more element openings. A user may utilize the one or more element openings to permit at least a portion of the guidewire <NUM> to pass through the locking element <NUM>.

In some embodiments, an internal passage defined by an element internal wall <NUM> extending through the locking element <NUM>. The internal wall <NUM> of the locking element <NUM> may not comprise a constant internal diameter along the entire length of the internal wall <NUM> of the locking element <NUM> (as shown in <FIG>). For example, the locking element <NUM> may include a first element opening <NUM> and a second element opening <NUM> of varying diameters that are located on opposite ends of the internal wall <NUM> (e.g., a distal end and a proximal end, respectively). In some embodiments, a diameter of the first element opening <NUM> of the locking element <NUM> can be larger than a diameter of the second element opening <NUM> of the locking element <NUM>. As such, the internal wall <NUM> may taper towards the smaller diameter of the second element opening <NUM>. The tapering may advantageously facilitate passage of at least a portion of the guidewire <NUM> through the locking element <NUM> in a proximal direction, while inhibiting the guidewire stop 92B from passing through the locking element <NUM> in a distal direction once the guidewire stop 92B has interlocked with the locking element <NUM>, as described herein. For example, the tapering of the internal wall <NUM> may facilitate guiding (e.g., funneling) a proximal end of the guidewire <NUM> through the locking mechanism <NUM>.

As illustrated in <FIG>, the diameter of the first element opening <NUM> may be larger than the guidewire <NUM> (e.g., including the guidewire stop 92B), but the diameter of the second element opening <NUM> may be smaller than at least the guidewire stop 92B. In some instances, the diameter of the second element opening <NUM> can be smaller than the outer width or diameter of the guidewire stop 92B, such that the internal wall <NUM> tapering towards the second element opening <NUM> can engage the guidewire stop 92B as the guidewire stop 92B passes through the locking element <NUM> (as shown in <FIG>).

The second element opening <NUM> may be comprise a similar sized to the opening <NUM>, such that the second element opening <NUM> allows a portion of the guidewire <NUM> proximal to the guidewire stop 92B to pass through and/or exit the internal cavity <NUM> of the locking mechanism <NUM>, while still maintaining a portion of the guidewire <NUM> (e.g., the guidewire stop 92B) within the internal cavity <NUM>. The second element opening <NUM> may be coaxially aligned with the opening <NUM>.

The locking element <NUM> can comprise any suitable shape and configuration capable of receiving and/or engaging the guidewire stop 92B to inhibit removal of the guidewire stop 92B in a distal direction from the locking element <NUM> once inserted. For example, as shown in <FIG>, the locking element <NUM> can comprise a generally cylindrical shape, although it will be appreciated that the locking element <NUM> can comprise any suitable wall structure (e.g., straight and/or curved) and have any suitable shape (e.g., cylindrical, rectangular, tapered). In some embodiments, the locking element <NUM> may be configured to temporarily resiliently or flexibly increase in size to permit the guidewire stop 92B to continue to pass through the locking element <NUM> in a proximal direction once the guidewire wire stop 92B initially engages the locking element <NUM>. The locking element <NUM>, in some instances, can be made of a variety of flexible or semi-rigid materials having adhesive-like properties such as a silicone gel. The locking element <NUM> can be formed by attaching an adhesive substance within the internal cavity <NUM> of the locking mechanism <NUM>.

The engaging and/or adhesive force of the locking element <NUM>, in some instances, may not be sufficient to engage with the guidewire <NUM> as the guidewire <NUM> is initially passed through the locking element <NUM>. In certain embodiments, the adhesive force of the locking element <NUM> on the guidewire <NUM> is insufficient to prevent movement of the guidewire <NUM> relative to the locking mechanism <NUM>. The adhesive force of the locking element <NUM> on the guidewire <NUM> may still permit relatively-free movement (e.g., with minimal resistance) of the guidewire <NUM> relative to the locking element <NUM> until the locking element <NUM> interlocks or engages with the guidewire stop 92B. For example, the locking element <NUM> may not sufficiently resist passage of the guidewire <NUM> through the locking element <NUM> before the locking element <NUM> engages the guidewire stop 92B. Once the locking element <NUM> engages with the guidewire stop 92B, the locking element <NUM> inhibits at least further distal movement of the guidewire <NUM> relative to the locking element <NUM>.

As illustrated in <FIG>, the locking mechanism <NUM> may be placed within the receptacle <NUM> of the dilator hub <NUM>. The locking mechanism <NUM> can be sized and configured to extend along and enclose any portion and/or length of the receptacle <NUM>. The locking mechanism <NUM> can be configured to be positioned within the dilator hub <NUM> through any mechanism described herein. The locking mechanism <NUM> can be removably engaged with at least a portion of the dilator hub <NUM> so that the locking mechanism <NUM> can move in or out of the receptacle <NUM> when the dilator hub <NUM> is slid in a proximal or distal direction, respectively, along the guidewire <NUM> once the locking mechanism <NUM> interlocks with the guidewire <NUM>. For example, the locking mechanism <NUM> may be removably held within the receptacle <NUM> via any suitable interaction (e.g., interference, engagement, friction, mechanical coupling, adhesion, etc.). In certain embodiments, once the locking mechanism <NUM> interlocks with the guidewire <NUM>, the guidewire <NUM> and locking mechanism <NUM> move in unison during removal of the guidewire <NUM>. For example, once the locking mechanism <NUM> interlocks with the guidewire <NUM>, further proximal movement of the guidewire <NUM> relative to the dilator <NUM> may be sufficient to overcome the interactive force removably holding the locking mechanism <NUM> within the receptacle <NUM>.

As described, an inner diameter of the second element opening <NUM> can be sufficiently large to permit a portion of the guidewire <NUM> to reside within and/or pass through the second element opening <NUM>. However, the inner diameter of the second element opening 348is not large enough to permit at least another portion of the guidewire <NUM> to pass through the second element opening <NUM> (e.g., the guidewire stop 92B). As such, the guidewire stop 92B may generally be too large to fit through the second element opening 348and further proximal movement of the guidewire <NUM> relative to the dilator hub <NUM> will engage the locking mechanism <NUM> with at least a portion of the guidewire <NUM> (e.g., the increased width of the guidewire stop 92B) to interlock the locking mechanism <NUM> with the guidewire <NUM>, as described with reference to <FIG>.

When the guidewire stop 92B engages with the locking mechanism <NUM>, the locking element <NUM> attaches to the guidewire stop 92B such that the locking mechanism <NUM> prevents the guidewire stop 92B from moving distally beyond the dilator hub <NUM>. As the guidewire <NUM> is moved in a proximal direction relative to the dilator hub <NUM> (shown in <FIG>), the guidewire stop 92B can abut against and/or engage the locking element <NUM>. The locking element <NUM> can engage the guidewire stop 92B to inhibit access of the guidewire stop 92B in a distal direction beyond the dilator hub <NUM>.

The embodiments herein described are comprised of conventional, biocompatible materials. For example, the needle preferably consists of ceramic, a rigid polymer, or a metal such as stainless steel, nitinol, or the like. The other elements can be formed of suitable polymeric materials, such as polycarbonate, nylon, polyethylene, high- density polyethylene, polypropylene, fluoropolymers and copolymers such as perfluoro (ethylene-propylene) copolymer, polyurethane polymers or co-polymers.

As noted above, the present access device can be used to place a catheter at other locations within a patient's body. Thus, for example, but without limitation, the access device can be used as or with a variety of catheters to drain fluids from abscesses, to drain air from a pneumotorax, and to access the peritoneal cavity.

Claim 1:
An access device (<NUM>) for placing a medical article within a body space, the access device (<NUM>) comprising:
a guidewire (<NUM>) having a guidewire stop (92A, 92B), the guidewire stop (92A, 92B) being shaped to enlarge a cross-sectional dimension of the guidewire (<NUM>) relative to adjacent sections of the guidewire (<NUM>);
a dilator (<NUM>) configured to be coaxially disposed about the guidewire (<NUM>);
characterized in that the access device (<NUM>) further comprises
a locking mechanism (<NUM>, <NUM>, <NUM>, <NUM>) being removably engaged with and disposed on the dilator (<NUM>) prior to the dilator (<NUM>) being coaxially disposed about the guidewire (<NUM>), the locking mechanism (<NUM>, <NUM>, <NUM>, <NUM>) comprising a portion having an opening being of a size and shape configured to receive the guidewire (<NUM>) and to inhibit the guidewire stop (92A, 92B) from passing through the opening, the locking mechanism (<NUM>, <NUM>, <NUM>, <NUM>) being configured to move from an unlocked state to a locked state, the locking mechanism (<NUM>, <NUM>, <NUM>, <NUM>) being disengaged from the guidewire (<NUM>) when the locking mechanism (<NUM>, <NUM>, <NUM>, <NUM>) is in the unlocked state so as to allow axial movement by the guidewire (<NUM>) through the locking mechanism (<NUM>, <NUM>, <NUM>, <NUM>) in a proximal direction and a distal direction relative to the dilator (<NUM>), the locking mechanism (<NUM>, <NUM>, <NUM>, <NUM>) being engaged with the guidewire (<NUM>) when the locking mechanism (<NUM>, <NUM>, <NUM>, <NUM>) is in the locked state so as to limit at least axial movement of a portion of the guidewire (<NUM>) in the distal direction relative to at least a portion of the dilator (<NUM>), the locking mechanism (<NUM>, <NUM>, <NUM>, <NUM>) and the dilator (<NUM>) further being configured to permit removal of the locking mechanism (<NUM>, <NUM>, <NUM>, <NUM>) from the dilator (<NUM>) by moving the guidewire (<NUM>) axially in a proximal direction relative to the dilator (<NUM>) with the guidewire stop (92A, 92B) abutting at least part of the portion of the locking mechanism (<NUM>, <NUM>, <NUM>, <NUM>) that the opening extends through.