Patent Description:
Commonly, conventional IV catheters are keep clear of clotting occlusions during their useful life by flushing the IV catheter periodically with saline or another suitable cleansing fluid or liquid. During the flushing process, the fluid is moved through the catheter to flush out any thrombus-forming clotting material contained within the catheter. Alternatively, some conventional IV catheters are keep clear of clotting occlusions by using an obturator to physically occupy a space within the IV catheter lumen. The obturator method is not universally accepted because it requires the doctor or nurse to place the obturator, which may have been recently exposed to an unsterile external environment, into the lumen of the catheter. This method may increase a risk of infection to the patient by positioning the obturator directly into the catheter such that the obturator may contact the patient's blood stream. Further, when the IV catheter is used in a therapy setting, the obturator must be removed and discard, and a replacement obturator is required.

Many conventional obturators are positioned with in the catheter in order to provide the occlusion prevention, and then removed to provide fluid aspiration and/or infusion therapy. The used obturator should be discarded after each use. This process must be repeated every time the IV catheter is accessed. In <CIT>, a catheter apparatus is provided for reducing blood clotting in connection with hemodialysis treatment. The catheter apparatus of <CIT> can comprise a first conduit defining an arterial lumen and a second conduit defining a venous lumen. In <CIT>, large staggered apertures can be provided in side walls of the conduits with at least one of the apertures having a cross-sectional area equal or greater than a cross-sectional area of one of the lumens. The catheter apparatus of <CIT> can further include first and second removable obturators adapted for axial insertion into the conduits and for occluding the apertures while so inserted. Advantageously in <CIT>, the obturators can wipe the apertures during removal, causing blood clots incident on the apertures to be dislodged from the apertures. <CIT> describes a convertible multi-lumen catheter that may be used for hemodialysis or other indications involving infusion and/or withdrawal of fluids from the body. As described in <CIT>, unlike existing catheters having a set number of lumens which may limit their utility as both short and long-term venous vascular devices, the catheter of the invention allows one or more additional lumens during the acute phase of catheter use with removal of these lumens (i.e. conversion) for more permanent use. A typical example of this would be a triple lumen device for hemodialysis and antibiotic therapy during an acute infection with conversion to a chronic dual lumen hemodialysis catheter after successful treatment of the infection. The lumen in <CIT> is permanently or semi-permanently blocked using a biocompatible plastic obturator that is inserted into the unused lumen and locked and/or glued into place. <CIT> describes an anti-clogging catheter includes a tubular cannula defining a fluid passageway and shaped and tipped to removably insert within and be removed from a human body, where the cannula has a proximal end with a first interior surface defining a first interior diameter and a distal end with a second interior surface defining a second interior diameter that is smaller than the first interior diameter. In <CIT>, a stylet is movable within the fluid passageway between the proximal end and the distal end and has an outer diameter substantially equal to the second interior diameter. <CIT> describes a bi-directional flow catheter for insertion into the body of a patient for the simultaneous introduction into and withdrawal therefrom of fluid. The catheter of <CIT> includes a primary tube having open distal and proximal ends, and a pair of branching tubes, each of which branch from a different side of the primary tube. The primary tube in <CIT> also has an opening in one side thereof to allow introduction of fluid. In <CIT> an elongate trocar/valve member is disposed in the primary tube and is movable longitudinally therein between an insert position and a flow position. One end of the trocar/valve member tapers to a cutting edge which protrudes from the opening in the distal end of the primary tube when the member is in the insert position, in <CIT>. The trocar/valve member of <CIT> is formed to prevent communication between the side opening and the opening in the distal end of the primary tube, and to cover the passageways between the primary tube and respective ones of the branching tubes when the member is in the insert position. In <CIT>, when the member is in the flow position, the cutting end thereof is withdrawn from the distal opening and communication is allowed between the side opening and one of the branching tubes and between the distal opening and the other of the branching tubes to thereby allow simultaneous introduction of fluid into and withdrawal of fluid from the body of a patient.

Objects of the invention are achieved with an obturator assembly as defined by claim <NUM>.

In one aspect, an obturator assembly, includes a hub forming a central passage. A catheter has a distal end and an opposing proximal end. The catheter includes a small-bore connector at the proximal end coupled to the hub. The catheter forms a lumen extending between the distal end and the proximal end of the catheter. The lumen is in fluid communication with the central passage. An obturator is movably positioned within the lumen. The obturator is movable between a first position and a second position. The obturator includes a distal end having a tip portion. With the obturator in the first position, the distal end limits fluid flow through the lumen and, with the obturator in the second position, the distal end provides a fluid flow path through the lumen.

Various embodiments are described below with reference to the drawings in which like elements generally are referred to by like numerals. The relationship and functioning of the various elements of the embodiments may better be understood by reference to the following detailed description. However, embodiments are not limited to those illustrated in the drawings. It should be understood that the drawings are not necessarily to scale, and in certain instances details may have been omitted that are not necessary for an understanding of embodiments disclosed herein, such as - for example -conventional fabrication and assembly.

The invention is defined by the claims, may be embodied in many different forms, and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey enabling disclosure to those skilled in the art. As used in this specification and the claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Reference herein to any industry standards (e.g., <NPL>) is defined as complying with the currently published standards as of the original filing date of this disclosure concerning the units, measurements, and testing criteria communicated by those standards unless expressly otherwise defined herein. The terms "proximal" and "distal" are used herein in the common usage sense where they refer respectively to a handle/doctor-end of a device or related object and a tool/patient-end of a device or related object. The terms "about," "substantially," "generally," and other terms of degree, when used with reference to any volume, dimension, proportion, or other quantitative or qualitative value, are intended to communicate a definite and identifiable value within the standard parameters that would be understood by one of skill in the art (equivalent to a medical device engineer with experience in this field), and should be interpreted to include at least any legal equivalents, minor but functionally-insignificant variants, standard manufacturing tolerances, and including at least mathematically significant figures (although not required to be as broad as the largest range thereof).

With reference to <FIG>, in example embodiments, an obturator assembly includes a catheter having a distal end and an opposing proximal end. The catheter forms a lumen extending between the distal end and the proximal end of the catheter. An obturator is movably positioned within the lumen between a first position and a second position. The obturator includes a distal tip portion. With the obturator in the first position, the distal tip portion prevents or limits fluid communication and/or fluid flow through the lumen. Conversely, with the obturator in the second position, the distal tip portion provides fluid communication and/or fluid flow through the lumen. The obturator can be locked or secured in the first position or the second position. The obturator is movable in at least one of a distal direction with respect to the distal end of the catheter or a proximal direction with respect to the distal end of the catheter from the first position to the second position. A hub forms a central passage that is in fluid communication with the lumen with the hub coupled to the catheter. A collar is operatively coupled to the hub and is configured in a locked configuration to prevent movement of the obturator within the lumen and in an unlocked configuration to allow movement of the obturator within the lumen. In the locked configuration, the collar is configured to prevent movement of the obturator within the lumen with the obturator in the first positon or the second position. The collar may be biased toward the locked configuration with the obturator in the first position or the second position. In example embodiments, at least a portion of the distal end of the obturator, e.g., at least a portion of a tip portion, has a symmetrical profile with respect to a central axis of the obturator or an asymmetrical profile with respect to the central axis.

The example embodiments described herein provide an obturator to prevent catheter occlusion that is not required to be removed prior to therapy. Rather, the multiple state obturator can be positioned in several states. For example, in a first or closed state, the obturator is configured to close or block a lumen of the catheter to prevent occlusion and/or undesirable reverse blood flow, for example. In a second state, the obturator can be moved within the lumen in a distal direction and/or an opposite proximal direction. Further, the obturator may have a reduced outer diameter in certain embodiments such that when the obturator is advanced, the obturator provides a fluid flow path or fluid opening to allow blood return or fluid infusion. As a result, the obturator does not have to be removed from the catheter lumen; thus, reducing a risk for infection and providing a reliable occlusion prevention mechanism. In particular embodiments, the obturator is made of a suitable translucent material to act as a conduit for light-based disinfectant technology used in reducing bioburden in the intraluminal space, for example. As described herein, the example multiple state obturator is selectively controllable to prevent or allow fluid flow through the catheter without having to be removed. The obturator assembly can remain installed for the duration of the therapy and provide both an anti-occlusion mechanism and an infusion capability.

In example embodiments, an obturator assembly includes an obturator positionable within a lumen of a device, such as a catheter. The obturator is movable between a first position and a second position. The obturator has a distal tip portion, wherein, with the obturator in the first position, the distal tip portion limits fluid communication through the lumen of the device and, with the obturator in the second position, the distal tip portion provides or allows fluid communication through the lumen of the device. The obturator is configured to move automatically in a distal direction with respect to a device, e.g., the catheter, toward a second or open position in response to a pressure causing fluid to flow through the catheter lumen in the distal direction to allow the fluid to be expressed from the distal opening of the lumen. With the pressure decreased or removed, the obturator is configured to move automatically toward a first or closed position. For example, a suitable pump operatively coupled to the obturator assembly may cycle to push fluid into the proximal end of the obturator assembly. In certain embodiments, the obturator includes a spring or another suitable biasing member biasing the spring obturator toward the closed position. The obturator is configured to automatically extend from the device, e.g., the catheter, in a distal direction to allow the fluid to exit the catheter lumen at the opposing distal end of the obturator assembly. Once the fluid has passed through the lumen and the fluid pressure within the lumen is decreased, e.g., removed, the obturator is configured to move automatically toward the first or closed position to seal the distal opening of the catheter. In particular embodiments, the pump may be configured to pump some fluid then reverse its peristaltic condition when used with a movable obturator to more fully re-seat the obturator in the sealed position.

Referring now to the figures, and initially to <FIG>, an example obturator assembly <NUM> includes a hub <NUM> forming a central passage <NUM> as shown in <FIG> and <FIG>. In example embodiments, central passage <NUM> extends between a distal end <NUM> and an opposing proximal end <NUM> of hub <NUM>. As used herein, the terms "distal" and "distally" refer to a location, a position, and/or a direction situated away from the hub, i.e., a point of origin or attachment, while the terms "proximal" and "proximally" refer to a location, a position and/or a direction situated toward the hub, i.e., the point of origin or attachment. Proximal end <NUM> of hub <NUM> is configured to removably couple to any suitable medical device or component, for example, standard medical tubing. As shown in <FIG> and <FIG>, for example, a suitable adapter <NUM> is formed on or coupled to proximal end <NUM> to facilitate coupling hub <NUM> to the medical device or tubing. In certain embodiments, hub <NUM> includes a small-bore connector configured to couple hub <NUM> to a medical device or tubing. The medical device or tubing may include a cooperating element <NUM> shown in <FIG>, such as a small-bore connector lock, to facilitate coupling the medical device or tubing, for example, to hub <NUM>.

A catheter <NUM> is operatively coupled to hub <NUM>. In example embodiments, catheter <NUM> has a distal end <NUM> and an opposing proximal end <NUM>. Catheter <NUM> may include a cannula extending from a distal end <NUM> toward an opposing proximal end <NUM> of catheter <NUM> in certain example embodiments. At proximal end <NUM>, catheter <NUM> includes an adapter or body, such as a small-bore connector <NUM> shown in <FIG> and <FIG>, for example, to couple proximal end <NUM> of catheter <NUM> to distal end <NUM> of hub <NUM>. In certain embodiments, small-bore connector <NUM> is a small-bore connector having a <NUM>% tapered fluid connection per ISO <NUM> for liquids and gases in healthcare applications. In example embodiments, catheter <NUM> forms or defines a lumen <NUM> extending between distal end <NUM> and proximal end <NUM> of catheter <NUM>. In example embodiments shown in <FIG> and <FIG>, lumen <NUM> is in fluid communication with central passage <NUM> to provide a fluid flow path through obturator assembly <NUM>. In example embodiments, each of lumen <NUM> and central passage <NUM> has a suitable diameter or a suitable cross-sectional dimension to facilitate fluid flow through obturator assembly <NUM>. More specifically, in certain embodiments, fluid flows around a distal end of an obturator, such as an obturator <NUM> described below, movably positioned in lumen <NUM> and into and through lumen <NUM> of catheter <NUM> with the obturator in an open position or configuration.

Referring further to <FIG>, obturator assembly <NUM> includes an obturator <NUM> movably positioned within lumen <NUM>. Obturator <NUM> is movable between a first position, such as a closed position shown in <FIG>, and a second position, such as an open position as shown in <FIG>. Obturator <NUM> has a distal end <NUM> and an opposing proximal end <NUM>. In certain embodiments, obturator <NUM> includes a tip portion <NUM> at distal end <NUM>. Tip portion <NUM> transitions into a body <NUM> in a midsection of obturator <NUM> and body <NUM> transitions into a base <NUM> at proximal end <NUM> of obturator <NUM>. In certain example embodiments as shown in <FIG>, body <NUM> and/or base <NUM> forms or defines a channel <NUM> providing fluid communication between lumen <NUM> and central passage <NUM>. In example embodiments, with obturator <NUM> in the first position, distal end <NUM> and, in certain embodiments, tip portion <NUM>, prevents or limits fluid communication and fluid flow through lumen <NUM>. With obturator <NUM> in the second position, distal end <NUM> and, in certain embodiments, tip portion <NUM>, provides fluid communication such that fluid is able to flow through lumen <NUM> into central passage <NUM> through channel <NUM>. In particular embodiments, obturator <NUM> is made of a suitable translucent material to act as a conduit for light-based disinfectant technology used in reducing bioburden in the intraluminal space, for example.

In example embodiments, with obturator <NUM> in the first position, distal end <NUM>, e.g., at least a portion of tip portion <NUM>, is positioned within lumen <NUM> to prevent fluid flow into lumen <NUM> and, with obturator <NUM> in the second position, distal end <NUM>, e.g., at least a portion of tip portion <NUM>, extends from catheter <NUM> in a distal direction to allow fluid flow into lumen <NUM>. Alternatively, in certain embodiments, with obturator <NUM> in the second position, distal end <NUM>, e.g., at least a portion of tip portion <NUM>, extends into lumen <NUM> of catheter <NUM> in a proximal direction to allow fluid flow into lumen <NUM>. In example embodiments described herein, obturator <NUM> is movable from the first position to the second position in a distal direction with respect to distal end <NUM> of catheter <NUM>, i.e., away from hub <NUM>, to extend beyond distal end <NUM> to provide a fluid flow path <NUM> as shown, for example, in <FIG>. Fluid flow path <NUM> provides fluid communication between lumen <NUM> and a lumen formed in a vessel, e.g., an artery or vein of a patient in which obturator assembly <NUM> is positioned. Referring to <FIG>, in example embodiments, obturator <NUM> may be used independently of the other components of obturator assembly <NUM> and/or catheter <NUM> or may be used with any suitable combination of one or more components of obturator assembly <NUM> and/or catheter <NUM>.

Referring again to <FIG>, in example embodiments, a fluid flow in obturator assembly <NUM>, e.g., through at least lumen <NUM>, is selectably controllable. For example, in certain example embodiments, obturator <NUM> is urged at proximal end <NUM>, e.g., by pushing at base <NUM> and/or hub <NUM>, to move obturator <NUM> in a first direction within lumen <NUM> in the distal direction with respect to distal end <NUM> of catheter <NUM> until distal end <NUM>, e.g., at least a portion of tip portion <NUM>, extends distally from lumen <NUM> of catheter <NUM> to provide fluid flow path <NUM> through lumen <NUM>, as shown in <FIG>. Conversely, in these embodiments obturator <NUM> is urged at proximal end <NUM>, e.g., by pulling at base <NUM> and/or hub <NUM>, to move obturator <NUM> in a second direction opposite the first direction within lumen <NUM> until distal end <NUM>, e.g., at least a portion of tip portion <NUM> is at least partially positioned within lumen <NUM> to close fluid flow path <NUM>, as shown in <FIG>. In certain embodiments, obturator <NUM> can be moved automatically in the distal direction and the proximal direction using a pump or another suitable device. In alternative example embodiments, obturator <NUM> is moveable in a proximal direction with respect to distal end <NUM> of catheter <NUM>, i.e., toward hub <NUM>, from the first position to the second position to extend into lumen <NUM> a suitable distance to provide a fluid flow path (not shown in the figures). The fluid flow path provides fluid communication between lumen <NUM> and the lumen formed in the patient's vessel.

Obturator assembly <NUM> includes one or more seals, such as one or more sleeve seals, formed plastic seals, O-ring seals, or any suitable seals known to those having ordinary skill in the art. In certain embodiments, one or more O-ring seals <NUM> or other suitable seals or gaskets, are positioned about an outer periphery <NUM> of proximal end <NUM> of obturator <NUM> and contact an inner surface <NUM> of small-bore connector <NUM> at proximal end <NUM> of catheter <NUM>. In certain embodiments, each O-ring seal <NUM> is positioned within a respective annular slot <NUM> formed in inner surface <NUM> of small-bore connector <NUM> to properly maintain O-ring seal <NUM> positioned about proximal end <NUM> of obturator <NUM> and between obturator <NUM> and catheter <NUM> to provide a fluid-tight seal within obturator assembly <NUM>.

Obturator <NUM> has a central axis <NUM>, shown in <FIG>, <FIG>, extending between distal end <NUM> and proximal end <NUM> of obturator <NUM>. In example embodiments, at least a portion of distal end <NUM>, e.g., at least a portion of tip portion <NUM>, has an asymmetrical profile, such as shown in <FIG> and <FIG>, with respect to central axis <NUM> or a symmetrical profile, as shown in <FIG>, with respect to central axis <NUM>. Distal end <NUM>, e.g., at least a portion of tip portion <NUM>, may have any suitable profile that provides the desired fluid flow through fluid flow path <NUM>. In certain conventional obturator assemblies, as a patient's blood is drawn past the distal end of an obturator and into a lumen of the cooperating catheter, shear forces exerted on the red blood cells may damage the red blood cells and may tear or rupture the red blood cells causing destruction and disassociation of the red blood cells, sometimes referred to as "hemolysis. " Unlike distal ends of conventional obturators, distal end <NUM> and, particularly, at least a portion of tip portion <NUM>, has a smooth, transitioning profile that facilitates administering or drawing fluids, e.g., blood, to or from the patient while preventing or limiting the damage and destruction of fluid material and the occurrence of hemolysis, for example.

In example embodiments, an amount of fluid flow (i.e., a volume of fluid) through fluid flow path <NUM> can be optimized by adjusting a cross-sectional area of an opening formed between an outer surface of obturator <NUM> and an inner wall of catheter <NUM> forming lumen <NUM>. For example, an outer diameter of obturator <NUM> and/or an inner diameter of catheter <NUM> at the distal end of catheter <NUM> may be adjusted to reduce hemolysis and provide a desired blood sample during a blood draw application. For example, referring to <FIG>, a relatively larger fluid flow path <NUM> may reduce or eliminate damage to the blood cells during the blood draw. Conversely, an equal amount of fluid flow through a smaller cross-sectional area, such as shown in <FIG>, may provide better infusion performance because the flow is equally divided around the distal end of obturator <NUM>.

As shown in <FIG>, <FIG>, and <FIG>, in example embodiments, obturator assembly <NUM> includes a collar, such as a locking collar <NUM>, operatively coupled to hub <NUM>. Locking collar <NUM> is configurable in a locked configuration, such as shown in <FIG>, to prevent movement of obturator <NUM> within lumen <NUM> and in an unlocked configuration, such as shown in <FIG>, to allow movement of obturator <NUM> in the distal direction and/or the opposite proximal direction within lumen <NUM>. In the locked configuration, locking collar <NUM> is configured to retain obturator <NUM> in a selected position, e.g., the first position or the second position. In <FIG>, locking collar <NUM> is in the locked configuration to retain obturator <NUM> in the first position, e.g., a closed position preventing fluid flow through lumen <NUM>, and prevent obturator from moving from the first position, e.g., to the second position. In <FIG>, locking collar <NUM> is in the unlocked configuration to allow obturator <NUM> to move with respect to catheter <NUM> in a distal direction or an opposite proximal direction. As shown in <FIG>, with locking collar <NUM> in the unlocked configuration, obturator <NUM> can be moved to the second position, e.g., an open position creating fluid flow path <NUM> to allow fluid flow into lumen <NUM>. In <FIG>, with locking collar <NUM> in the locked configuration, obturator <NUM> is retained in the second position, e.g., the open position creating fluid flow path <NUM>, and prevented from moving from the second position, e.g., to the first position.

In certain embodiments, locking collar <NUM> includes a tab <NUM> positionable within or configured to interfere with a depression <NUM> formed in obturator <NUM> with locking collar <NUM> in the locked configuration. Tab <NUM> is actuatable to allow locking collar <NUM> to move between the locked configuration and the unlocked configuration. For example, in example embodiments, tab <NUM> is depressed to allow locking collar <NUM> to move from the locked configuration to the unlocked configuration, which allows obturator <NUM> to move between the first position and the second position. In certain example embodiments, locking collar <NUM> is biased toward the locked configuration in one of the first position and the second position. More specifically, tab <NUM> may be biased, using a spring or other suitable biasing member (not shown in the figures), toward the locked configuration in one of the first position and the second position.

Referring to <FIG>, in alternative example embodiments, one or more diffuser openings <NUM> are formed through catheter <NUM> to provide fluid communication between lumen <NUM> and a lumen formed in a vessel, e.g., an artery or vein of a patient in which obturator assembly <NUM> is positioned. In these embodiments, at least a portion of distal end <NUM>, e.g., at least a portion of tip portion <NUM>, has an asymmetrical profile, such as shown in <FIG>, with respect to central axis <NUM> or a symmetrical profile, as shown in <FIG>, with respect to central axis <NUM>. Distal end <NUM>, e.g., at least a portion of tip portion <NUM>, has a suitable length along central axis <NUM> such that, with obturator <NUM> in the closed position, distal end <NUM> extends into lumen <NUM> to seal the distal opening to lumen <NUM> as well as seal each diffuser opening <NUM> formed in catheter <NUM> to prevent or limit fluid flow through lumen <NUM>, as shown in <FIG>. As shown in <FIG> and <FIG>, with obturator <NUM> in a fully open position, fluid is allowed to flow through the distal opening of lumen <NUM> as well as through one or more diffuser openings <NUM>. In a particular embodiment not shown in the figures, obturator <NUM> having an asymmetrical profile may seal one or more diffuser openings <NUM> preventing fluid flow through the sealed diffuser openings <NUM> while allowing fluid flow through diffuser openings nearest the asymmetrical aspect of obturator <NUM>. Depending on the application of obturator assembly <NUM>, fluid is allowed to flow into (e.g., fluid infusion) and/or out of (e.g., aspiration of fluid/blood drawn) lumen <NUM> through the distal opening of lumen <NUM> and diffuser openings <NUM>. However, as shown in <FIG>, with obturator <NUM> in an intermediate or partially open position, distal end <NUM>, e.g., at least a portion of tip portion <NUM>, extends into lumen <NUM> to seal the distal opening to lumen <NUM> but provides fluid communication or allows fluid flow through diffuser openings <NUM> formed in catheter <NUM>. Again, depending on the application of obturator assembly <NUM>, fluid is allowed to flow into and/or out of lumen <NUM> through diffuser openings <NUM> with the obturator in the partially open position. In these alternative embodiments, obturator <NUM> is configured to occlude diffuser holes <NUM> as well as the distal opening of lumen <NUM>. This provides an added benefit of preventing occlusion at distal end <NUM> of catheter <NUM> and in or around diffuser openings <NUM>. Diffuser openings <NUM> also provide an added benefit for blood draws by providing additional aspiration through diffuser openings <NUM> to further reduce hemolysis and may also be utilized for high-pressure injection.

<FIG> illustrates an example method <NUM> for selectively controlling a fluid flow in an obturator assembly. In example embodiments, the obturator assembly includes a catheter forming a lumen and an obturator positioned within the lumen and movable between a first position and a second position. The method includes moving <NUM> the obturator in a first direction within the lumen in one of a distal direction and a proximal direction with respect to a distal end of the catheter to provide a fluid flow path through the lumen. Moving <NUM> may include urging a proximal end of the obturator to move the obturator in a first direction within the lumen in a distal direction with respect to a distal end of the catheter, for example, to provide a fluid flow path through the lumen. As desired, the method also includes moving <NUM> the obturator in a second direction opposite the first direction within the lumen until the distal end, e.g., at least a portion of the tip portion, of the obturator is at least partially positioned within the lumen to close the fluid flow path. Moving <NUM> may include urging the proximal end of the obturator to move the obturator in a second direction opposite the first direction within the lumen until the distal end, e.g., at least a portion of the tip portion, of the obturator is at least partially positioned within the lumen to close the fluid flow path.

A collar, such as a locking collar, is operatively coupled to the hub of the obturator assembly. In example embodiments, the method includes configuring <NUM> the collar in a locked configuration to prevent movement of the obturator within the lumen or in an unlocked configuration to allow movement of the obturator in the distal direction and/or the opposite proximal direction within the lumen. In the locked configuration, the collar is configured to retain the obturator in a selected position, e.g., the first position or the second position. For example, the collar can be positioned in the locked configuration to retain the obturator in the first position, e.g., a closed position preventing fluid flow through the lumen, and prevent the obturator from moving from the first position, e.g., to the second position. The collar can also be positioned in the locked configuration to retain the obturator in the second position, e.g., the open position creating a fluid flow path, and prevent the obturator from moving from the second position, e.g., to the first position. The collar can also be positioned in the unlocked configuration to allow the obturator to move with respect to the catheter in a distal direction or an opposite proximal direction. With the collar in the unlocked configuration, the obturator can be moved between the first position and the second position, for example. In certain example embodiments, the collar is biased toward the locked configuration in one of the first position and the second position. More specifically, a tab of the collar may be biased, using a spring or other suitable biasing member, toward the locked configuration in one of the first position and the second position.

Claim 1:
An obturator assembly (<NUM>), comprising:
a hub (<NUM>) forming a central passage (<NUM>);
a catheter (<NUM>) having a distal end (<NUM>) and an opposing proximal end (<NUM>), the catheter (<NUM>) including a small-bore connector (<NUM>) at the proximal end coupled to the hub (<NUM>), the catheter (<NUM>) forming a lumen (<NUM>) extending between the distal end and the proximal end of the catheter (<NUM>), the lumen (<NUM>) in fluid communication with the central passage (<NUM>); and
an obturator (<NUM>) movably positioned within the lumen (<NUM>), the obturator movable between a first position and a second position, the obturator (<NUM>) including a distal end (<NUM>) having a tip portion (<NUM>), wherein, with the obturator (<NUM>) in the first position, the distal end (<NUM>) of the obturator (<NUM>) limits fluid flow through the lumen (<NUM>) and, with the obturator (<NUM>) in the second position, the distal end (<NUM>) of the obturator (<NUM>) provides a fluid flow path through the lumen (<NUM>);
further comprising: a locking collar (<NUM>) operatively coupled to the hub (<NUM>), the locking collar (<NUM>) configurable in a locked configuration to prevent movement of the obturator (<NUM>) within the lumen (<NUM>) and in an unlocked configuration to allow movement of the obturator (<NUM>) within the lumen (<NUM>), wherein, in the locked configuration, the locking collar (<NUM>) is configured to prevent movement of the obturator (<NUM>) within the lumen (<NUM>) whether the obturator (<NUM>) is in the first position or in the second position, wherein the locking collar (<NUM>) comprises a tab configured to selectively interfere with a depression (<NUM>) formed in the obturator (<NUM>) with the locking collar (<NUM>) in the locked configuration.