Patent Publication Number: US-2023143159-A1

Title: Smart obturator assembly

Description:
RELATED APPLICATIONS 
     This application is a continuation of U.S. Pat. Application No. 16/709,645, filed Dec. 10, 2019, and entitled SMART OBTURATOR ASSEMBLY, which is a continuation of U.S. Pat. Application No. 15/697,165, filed Sep. 6, 2017, and entitled SMART OBTURATOR ASSEMBLY, which are incorporated herein in their entirety. 
    
    
     TECHNICAL FIELD 
     The present application relates generally to an obturator assembly. More specifically, the present application relates to a smart obturator assembly including an obturator movably positioned within a catheter to selectively control a fluid flow through the catheter and a sensor assembly at a distal end of the obturator to sense environmental characteristics including, for example, different markers, proteins, and/or chemicals in the patient’s blood stream. 
     BACKGROUND 
     Conventional obturators are utilized to prevent an IV catheter from becoming occluded with clotting blood. If the IV catheter remains open after use, blood can reflux back into the catheter tip and begin to coagulate, obstructing a flow of blood through the tip portion of the IV catheter and preventing continued use of the IV catheter for subsequent therapy. When this happens, the IV catheter must be removed and a replacement IV catheter set to gain vascular access. Bio-films and fibrin can also form over the tip portion of the IV catheter and obstruct blood flow into the IV catheter. In an attempt to prevent this obstruction, some conventional obturators are formed of a solid plastic piece that is inserted from a proximal end of the IV catheter to close or seal the opening of the lumen at the distal end of the IV catheter. The conventional obturator includes an adapter, such as a Luer connector lock, that fits on the proximal end to create a fluid-tight seal, while the distal tip portion of the obturator is positioned in the distal end of the IV catheter to prevent the IV catheter from becoming occluded. Introducing the conventional obturator through the proximal end of the catheter may increase a risk of patient infection. 
     BRIEF SUMMARY 
     In one aspect, a smart obturator assembly suitable for use with a device, such as a catheter, includes a hub forming a central passage. An obturator is movably positionable within a lumen of the device operatively coupled to the hub. The obturator is movable within the lumen between a first position and a second position. The obturator includes a distal end having a tip portion and an opposing proximal end and a sensor at the distal end of the obturator. 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 fluid flow through the lumen. 
     In another aspect, a smart obturator assembly suitable for use with a device, such as a catheter, includes a hub forming a central passage. A collar on the hub includes electronic circuitry in signal communication with remote reception circuitry. An obturator is movably positionable within a lumen of the device, wherein the hub is coupled to a proximal end of the device such that the central passage is in fluid communication with the lumen. The obturator is movable within the lumen between a first position and a second position. The obturator includes a distal end and a sensor at the distal end. The sensor is configured to sense an environmental characteristic within a patient’s blood stream, generate a signal representative of the environmental characteristic, and transmit the signal to the electronic circuitry. The electronic circuitry is configured to receive the signal and transmit the signal to the remote reception circuitry. 
     In yet another aspect, a smart obturator assembly suitable for use with a device, such as a catheter, includes an obturator movably positionable within a lumen of the device. The obturator is movable within the lumen between a first position and a second position. The obturator has a distal end and a sensor assembly at the distal end. The sensor assembly is configured to sense one or more environmental characteristics within a patient’s blood vessel and to generate one or more signals representative of the one or more environmental characteristics. A hub forming a central passage is coupled to the device such that the central passage is in fluid communication with the lumen. A collar is operatively coupled to the hub. The collar includes electronic circuitry in signal communication with the sensor. The electronic circuitry is configured to receive the one or more signals and transmit the one or more signals to remote reception circuitry. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a perspective side view of an example obturator assembly in a closed fluid flow path configuration according to example embodiments; 
         FIG.  2    is a partial perspective side view of the example obturator assembly shown in  FIG.  1   ; 
         FIG.  3    is a perspective side view of an example obturator assembly in an open fluid flow path configuration according to example embodiments; 
         FIG.  4    is a partial perspective side view of the example obturator assembly shown in  FIG.  3   ; 
         FIG.  5    is a schematic side view of an example obturator assembly in a locked closed fluid flow path configuration according to example embodiments; 
         FIG.  6    is a schematic side view of an example obturator assembly in an unlocked open fluid flow path configuration according to example embodiments; 
         FIG.  7    is a schematic side view of an example obturator assembly in a locked open fluid flow path configuration according to example embodiments; 
         FIG.  8    is a partial perspective side view of an example obturator assembly according to example embodiments; 
         FIG.  9    is an exploded, partial perspective side view of an example obturator assembly according to example embodiments; 
         FIG.  10    is a partial perspective side view of an example obturator assembly including a distal end of the obturator flush with a distal end of the catheter according to example embodiments; 
         FIG.  11    is a partial perspective side view of an example obturator assembly including a distal end of the obturator proud of a distal end of the catheter according to example embodiments; 
         FIG.  12    is a partial perspective side view of an example obturator assembly including a distal end of the obturator recessed in a distal end of the catheter according to example embodiments; 
         FIG.  13    is a partial perspective side view of an example obturator including a sensor assembly proud of a distal end of the catheter according to example embodiments; 
         FIG.  14    is a partial perspective side view of an example obturator assembly with a distal end of the obturator flush with a distal end of the catheter according to example embodiments; 
         FIG.  15    is a partial perspective side view of an example obturator assembly with a distal end of the obturator flush with a distal end of the catheter according to example embodiments; and 
         FIG.  16    illustrates steps of an example method for operating an example obturator assembly according to example embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     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., ASTM, ANSI, IEEE, ISO standards) 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). 
     A smart obturator assembly includes a sensor assembly to provide sensing capabilities for a device, such as an IV catheter, and allow access through the IV catheter. The sensor assembly can provide valuable sensing data for one or more environmental characteristics including, without limitation, temperature, potassium, glucose, sodium, pregnancy testing, drug concentration levels, or any combination thereof. The obturator is selectively movable within the catheter to prevent or limit catheter occlusions and provide a fluid flow path for infusion or aspiration of fluids, for example, without removing the obturator from the catheter lumen. 
     The smart obturator assembly can be used to access a patient’s vein or artery. For example, for application within the artery, the sensor assembly may include a pressure transducer configured to measure and communicate the patient’s blood pressure in real time. Conventional methods for measuring a patient’s blood pressure in an artery line requires an extension set, setup, maintenance, and flushing. The embodiments described herein will help to eliminate the need for additional tubing, sets, flushing, and maintenance, for example. When used in the venous system, the smart obturator assembly is configured to measure a temperature or potassium, blood glucose, and/or sodium levels, and any combination thereof, for example. If the data shows that a particular therapy is required, the smart obturator assembly is configured to signal the clinician or the pump nearby. The smart obturator assembly may also be used with a patient control dose of pain medicine or with near real-time blood glucose monitoring and automatic dosing of insulin, for example. 
     In example embodiments, an obturator assembly suitable for use with a device, such as 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 positionable within the lumen and movable 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 position 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 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. 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, the obturator includes a distal end having a tip portion and an opposing proximal end. A sensor assembly at the tip portion is configured to sense one or more environmental characteristics, generate one or more signals representative of the one or more environmental characteristics, and transmit the one or more signals to a hub or a collar, such as the locking collar of the obturator assembly. In example embodiments, the collar includes electronic circuitry, or a suitable electronic connection coupled in signal communication with the sensor assembly. The electronic circuitry, for example, is configured to receive the one or more signals and transmit or pass-through the one or more signals to remote reception circuitry and/or display a datum representative of the one or more environmental characteristics on a display in the hub, the collar, or another suitable component operatively coupled to the obturator. 
     As described herein, an example smart obturator assembly includes a sensor assembly having a sensor or an array of sensors at the distal end of the obturator, e.g., at or near the tip portion of the distal end of the obturator and/or at or near the distal end of the catheter. In certain example embodiments, each sensor is positioned within a vein or an artery to directly contact the patient’s blood stream. Each sensor is operatively coupled to the electronic circuitry using lead wires that are molded into or are attached to an outside surface or an inside surface of the obturator, for example. In example embodiments, the collar at the proximal end of the obturator assembly is configured with one or more of a variety of electronic and/or communication components to provide power, data transmission, data collection, and data analysis capabilities, as well as other capabilities. 
     Each sensor may be configured to sense one or more environmental characteristics including, without limitation, different markers, proteins, and/or chemicals in the patient’s blood stream. Alternatively, the sensor assembly may include an array of sensor, with each sensor configured to sense one or more environmental characteristics. The sensor assembly may be integrally formed with the obturator or the sensor assembly may be modularized. In certain example embodiments, the obturator provides a socket or a recessed area for housing the sensor assembly. One or more electrical contacts, e.g., one or more conductive pads, are positioned within or near the recessed area for electrical communication with the sensor assembly. For example, two conductive pads electrically couple the sensor assembly and a thermocouple operatively coupled to the collar or the electronic circuitry on or in the collar to sense a temperature. In alternative example embodiments, a wire configuration including a plurality of lead wires may be operatively coupled to the electronic circuitry to provide suitable communication protocols, e.g., USB level communication, which can enable a wide range of sensors, data rates and/or data types on a well-defined BUS. Other suitable communication protocols include, for example, simple plugin, Wi-Fi, Bluetooth° wireless technology, a universal serial bus connector, Radio Frequency Identification (RFID), Near Field Communication (NCF, a derivative of RFID), and self-contained displays. The distal end of the obturator and/or the sensor assembly may be flush with the distal end of the catheter, proud of the distal end of the catheter (i.e., extend past the distal end of the catheter) or recessed into the distal end of the catheter (i.e., proximal to the distal end of the catheter) depending on a desired configuration for a particular sensor or sensor array. The sensor assembly may also provide access through the catheter for in-vivo monitoring as desired. 
     In certain example embodiments, the obturator assembly has a customizable interface between the obturator and the catheter. This customization may be accomplished with features on the catheter adapter (e.g., a small-bore connector having a 6% tapered fluid connection per International Standard ISO 80369 for liquids and gases in healthcare applications) that must be present in order for the sensor assembly to work properly or with added features. In certain embodiments, a bump, projection, or suitable feature may be present when operatively coupling the obturator to the catheter to sense the bump, projection, or feature and allow the obturator assembly to work properly. As such the obturator assembly can fit properly with catheters having slightly different catheter diameters, lengths, and/or relevant dimensions. Thus, the embodiments described herein may be configured to work properly with various catheters to ensure that the obturator assembly safely and effectively occludes the lumen opening at the distal end of the catheter, as well as provides desired sensing capabilities. 
     Referring now to the figures, and initially to  FIGS.  1 - 4   , an example obturator assembly  10  suitable for use with a device, such as a catheter, having a lumen between a distal end and a proximal end of the device, includes a hub  12  forming a central passage  14  as shown in  FIGS.  1  and  3   . In example embodiments, central passage  14  extends between a distal end  16  and an opposing proximal end  18  of hub  12 . 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  18  of hub  12  is configured to removably couple to any suitable medical device or component, for example, standard medical tubing. As shown in  FIGS.  1  and  3   , for example, a suitable adapter  20  is formed on or coupled to proximal end  18  to facilitate coupling hub  12  to the medical device or tubing. In certain embodiments, hub  12  includes a small-bore connector configured to couple hub  12  to a medical device or tubing. The medical device or tubing may include a cooperating element  21  shown in  FIG.  3   , such as a small-bore connector lock, to facilitate coupling the medical device or tubing, for example, to hub  12 . 
     Hub  12  is configured to operatively couple to a device, such as a catheter  22 . In example embodiments, catheter  22  has a distal end  24  and an opposing proximal end  26 . Catheter  22  may include a cannula extending from a distal end  24  toward an opposing proximal end  26  of catheter  22  in certain example embodiments. At proximal end  26 , catheter  22  includes an adapter or body, such as a small-bore connector  28  shown in  FIGS.  1  and  3   , for example, to couple proximal end  26  of catheter  22  to distal end  16  of hub  12 . In certain embodiments, small-bore connector  28  is a small-bore connector having a 6% tapered fluid connection per International Standard ISO 80369 for liquids and gases in healthcare applications. In example embodiments, catheter  22  forms or defines a lumen  30  extending between distal end  24  and proximal end  26  of catheter  22 . In example embodiments shown in  FIGS.  1  and  3   , lumen  30  is in fluid communication with central passage  14  to provide a fluid flow path through obturator assembly  10 . In example embodiments, each of lumen  30  and central passage  14  has a suitable diameter or a suitable cross-sectional dimension to facilitate fluid flow through obturator assembly  10 . 
     Referring further to  FIGS.  1 - 4   , obturator assembly  10  includes an obturator  40  movably positionable within lumen  30 . Obturator  40  is movable within lumen  30  between a first position, such as a closed position shown in  FIG.  1   , and a second position, such as an open position as shown in  FIG.  3   . Obturator  40  has a distal end  42  and an opposing proximal end  44 . In certain embodiments, obturator  40  includes a tip portion  46  at distal end  42 . Tip portion  46  transitions into a body  48  in a midsection of obturator  40  and body  48  transitions into a base  50  at proximal end  44  of obturator  40 . In certain example embodiments as shown in  FIGS.  5 - 7   , body  48  and/or base  50  forms or defines a channel  52  providing fluid communication between lumen  30  and central passage  14 . In example embodiments, with obturator  40  in the first position, distal end  42  and, in certain embodiments, tip portion  46 , prevents or limits fluid communication and fluid flow through lumen  30 . With obturator  40  in the second position, distal end  42  and, in certain embodiments, tip portion  46 , provides fluid communication such that fluid is able to flow through lumen  30  into central passage  14  through channel  52 . 
     In example embodiments, with obturator  40  in the first position, distal end  42 , e.g., at least a portion of tip portion  46 , is positioned within lumen  30  to prevent fluid flow into lumen  30  and, with obturator  40  in the second position, distal end  42 , e.g., at least a portion of tip portion  46 , extends from catheter  22  in a distal direction to allow fluid flow into lumen  30 . Alternatively, in certain embodiments, with obturator  40  in the second position, distal end  42 , e.g., at least a portion of tip portion  46 , extends into lumen  30  of catheter  22  in a proximal direction to allow fluid flow into lumen  30 . In example embodiments described herein, obturator  40  is movable from the first position to the second position in a distal direction with respect to distal end  24  of catheter  22 , i.e., away from hub  12 , to extend beyond distal end  24  to provide a fluid flow path  54  as shown, for example, in  FIG.  4   . Fluid flow path  54  provides fluid communication between lumen  30  and a lumen formed in a vessel, e.g., an artery or vein of a patient in which obturator assembly  10  is positioned. Referring to  FIGS.  1 - 4   , in example embodiments, obturator  40  may be used independently of the other components of obturator assembly  10  and/or catheter  22  or may be used with any suitable combination of one or more components of obturator assembly  10  and/or catheter  22 . 
     Referring now to  FIGS.  5 - 7   , in example embodiments, a fluid flow in obturator assembly  10 , e.g., through at least lumen  30 , is selectably controllable. For example, in certain example embodiments, obturator  40  is urged at proximal end  44 , e.g., by pushing at base  50  and/or hub  12 , to move obturator  40  in a first direction within lumen  30  in the distal direction with respect to distal end  24  of catheter  22  until distal end  42 , e.g., at least a portion of tip portion  46 , extends distally from lumen  30  of catheter  22  to provide fluid flow path  54  through lumen  30 , as shown in  FIGS.  6  and  7   . Conversely, in these embodiments obturator  40  is urged at proximal end  44 , e.g., by pulling at base  50  and/or hub  12 , to move obturator  40  in a second direction opposite the first direction within lumen  30  until distal end  42 , e.g., at least a portion of tip portion  46  is at least partially positioned within lumen  30  to close fluid flow path  54 , as shown in  FIG.  5   . In certain embodiments, obturator  40  can be moved in the distal direction and the proximal direction using a pump or another suitable device. In alternative example embodiments, obturator  40  is moveable in a proximal direction with respect to distal end  24  of catheter  22 , i.e., toward hub  12 , from the first position to the second position to extend into lumen  30  a suitable distance to provide a fluid flow path (not shown in the figures). The fluid flow path provides fluid communication between lumen  30  and the lumen formed in the patient’s vessel. 
     Obturator assembly  10  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  56  or other suitable seals or gaskets, positioned about an outer periphery  58  of proximal end  44  of obturator  40  and contacting an inner surface  60  of small-bore connector  28  at proximal end  26  of catheter  22 . In certain embodiments, each O-ring seal  56  is positioned within a respective annular slot  62  formed in inner surface  60  of small-bore connector  28  to properly maintain O-ring seal  56  positioned about proximal end  44  of obturator  40  and between obturator  40  and catheter  22  to provide a fluid-tight seal within obturator assembly  10 . 
     Obturator  40  has a central axis  70 , shown in  FIGS.  2  and  4   , extending between distal end  42  and proximal end  44  of obturator  40 . In example embodiments, at least a portion of distal end  42 , e.g., at least a portion of tip portion  46 , has an asymmetrical profile, such as shown in  FIG.  2   , with respect to central axis  70  or a symmetrical profile, as shown in  FIG.  4   , with respect to central axis  70 . Distal end  42 , e.g., at least a portion of tip portion  46 , may have any suitable profile that provides the desired fluid flow through fluid flow path  54 . 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 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, at least a portion of distal end  42  and, particularly, at least a portion of tip portion  46 , 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  54  can be optimized by adjusting a cross-sectional area of an opening formed between an outer surface of obturator  40  and an inner wall of catheter  22  forming lumen  30 . For example, an outer diameter of obturator  40  and/or an inner diameter of catheter  22  at the distal end of catheter  22  may be adjusted to reduce hemolysis and provide a desired blood sample during a blood draw application. A relatively larger fluid flow path  54  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 may provide better infusion performance because the flow is equally divided around the distal end of obturator  40 . 
     As shown in  FIGS.  1 ,  3 , and  5 - 7   , in example embodiments, obturator assembly  10  includes a collar, such as a locking collar  72 , operatively coupled to hub  12 . Locking collar  72  is configurable in a locked configuration, such as shown in  FIGS.  5  and  7   , to prevent movement of obturator  40  within lumen  30  and in an unlocked configuration, such as shown in  FIG.  6   , to allow movement of obturator  40  in the distal direction and/or the opposite proximal direction within lumen  30 . In the locked configuration, locking collar  72  is configured to retain obturator  40  in a selected position, e.g., the first position or the second position. In  FIG.  5   , locking collar  72  is in the locked configuration to retain obturator  40  in the first position, e.g., a closed position preventing fluid flow through lumen  30 , and prevent obturator from moving from the first position, e.g., to the second position. In  FIG.  6   , locking collar  72  is in the unlocked configuration to allow obturator  40  to move with respect to catheter  22  in a distal direction or an opposite proximal direction. As shown in  FIG.  6   , with locking collar  72  in the unlocked configuration, obturator  40  can be moved to the second position, e.g., an open position creating fluid flow path  54  to allow fluid flow into lumen  30 . In  FIG.  7   , with locking collar  72  in the locked configuration, obturator  40  is retained in the second position, e.g., the open position creating fluid flow path  54 , and prevented from moving from the second position, e.g., to the first position. 
     In certain embodiments, locking collar  72  includes a tab  74  positionable within or configured to interfere with a depression  76  formed in obturator  40  with locking collar  72  in the locked configuration. Tab  74  is actuatable to allow locking collar  72  to move between the locked configuration and the unlocked configuration. For example, in example embodiments, tab  74  is depressed to allow locking collar  72  to move from the locked configuration to the unlocked configuration, which allows obturator  40  to move between the first position and the second position. In certain example embodiments, locking collar  72  is biased toward the locked configuration in one of the first position and the second position. More specifically, tab  74  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 further to  FIGS.  8 - 15   , in example embodiments, obturator  40  forms a recessed area  78  at distal end  42  of obturator  40 . A sensor assembly  80  is positioned at or near distal end  42 , e.g., on distal end  42  and/or at least partially within recessed area  78  at tip portion  46 . In example embodiments, such as shown in  FIGS.  10 - 12   , sensor assembly  80  is positioned within recessed area  78  such that an end surface  82  of sensor assembly  80  is flush with an end surface  84  of obturator  40  at distal end  42 . In alternative example embodiments, sensor assembly  80  may be only partially positioned within recessed area  78  such that end surface  82  extends outwardly from end surface  84  of obturator  40  at distal end  42 . Referring further to  FIGS.  14  and  15   , in certain example embodiments, sensor assembly  80  has a constant diameter along a length of sensor assembly  80 . An outer diameter of obturator  40  at distal end  42  may vary to properly fit in a lumen of differently-sized catheters, e.g.,  14 ,  16 ,  18 ,  20 , and  22  gauge catheters. In particular embodiments, the size, i.e., a diameter and/or a length, of sensor assembly  80  is minimized to fit in smaller-sized catheters. Sensor assembly  80  may be coupled to distal end  42  by press-fitting, molding, gluing, snapping, or pinning sensor assembly  80  to distal end  42 , for example. Other coupling means known to those skilled it the art may be used to couple sensor assembly  80  to distal end  42 . 
     Sensor assembly  80  is configured to sense one or more environmental characteristics within or related to a patient’s blood or blood stream and generate and transmit one or more signals representative of the one or more environmental characteristics. For example, in example embodiments, sensor assembly  80  includes one or more sensors  90 , e.g., one sensor  90  or a plurality of sensors  90 . Referring further to  FIGS.  9  and  13   , for example, each sensor  90  is positioned at or on end surface  82  of sensor assembly  90 , as shown in  FIGS.  9  and  13   , and/or positioned on a perimeter surface  94  of sensor assembly  80 , as shown in  FIG.  13   . In example embodiments, each sensor  90  of sensor assembly  80  is configured to measure one or more environmental characteristics including, without limitation, a temperature within a body lumen, a blood glucose level, a sodium level, a potassium level, a drug concentration level, a white blood cell count, a blood pressure within the body lumen, or any combination thereof. Further, sensor assembly  80  may include one or more particular sensors  90  including, without limitation, a temperature sensor, a sensor that senses a chemical within a patient’s blood, a sensor that senses a marker in the patient’s blood, a sensor that senses a protein in the patient’s blood, or any combination thereof. 
     In example embodiments, sensor assembly  80  includes a plurality of sensors  90 , as shown in  FIGS.  9  and  13   . Each sensor  90  is electrically coupled to, e.g., coupled in signal communication with, an electronic circuit board  96  of sensor assembly  80 . A first electrical contact interface  98  including one or more first electrical contacts, such as one or more spring contacts  100 , e.g., a plurality of spring contacts, is electrically coupled to, e.g., coupled in signal communication with, electronic circuit board  96 . With sensor assembly  80  positioned within recessed area  78 , first electrical contact interface  98  is electrically coupled to a second electrical contact interface  102  positioned on and/or in distal end  42  of obturator  40  to electrically coupled second electrical contact interface  102  with sensor assembly  80 . Second electrical contact interface  102  includes one or more second electrical contacts, such as one or more contact pads  104 . Each contact pad  104  of the one or more contact pads  104  is electrically coupled to a respective spring contact  100  of the one or more spring contacts  100 . Referring further to  FIGS.  8  and  9   , one or more electrical lead wires  106 , e.g., a plurality of lead wires  106 , extend through obturator  40  to electrically couple, e.g., couple in signal communication, sensor assembly  80  via second electrical contact interface  102  with electronic circuitry  108 , operatively coupled to hub  12  and/or locking collar  72 , as shown in  FIG.  1   . In example embodiments, electric circuitry  108  is positioned on and/or within locking collar  72 . In certain example embodiments, each electrical lead wire  106  is molded onto tip portion  46  or molded into tip portion  46 . Electrical lead wire  106  may extend along a surface of a wall of obturator  40  or may be embedded or molded within at least a portion of a length of the obturator wall between distal end  42  and proximal end  44 . 
     Referring further to  FIG.  1   , electronic circuitry  108  is configured to transmit or pass-through signals to and receive signals from sensor assembly  80 . Electronic circuitry  108  is also configured to transmit signals to and receive signals from remote reception circuitry  110  including an external processor operatively coupled to electronic circuitry  108 . Additionally or alternatively, electronic circuitry  108  may be configured to display a datum representative of the one or more environmental characteristics on a display (not shown) on or in hub  12  or on or in locking collar  72 , for example. In certain embodiments, communication circuitry  112  in locking collar  72  is electrically coupled to, e.g., coupled in signal communication with, electronic circuitry  108  for wireless communication with remote reception circuitry  110  or an external processor. In these embodiments, communication circuitry  112  includes a radio frequency identification transmitter, a near field communication transmitter, a Bluetooth ®  wireless technology transmitter, a universal serial bus connector, or any suitable combination thereof. In particular embodiments, a connection port  114 , e.g., a USB port, on and/or in locking collar  72  is configured for connecting electronic circuitry  108  with remote reception circuitry  110  or an external processor. Locking collar  72  may also include a compartment  116  housing a power source  118 , e.g., a battery pack, as shown in  FIG.  1    electrically coupled to electronic circuitry  108  to provide power to electronic circuitry  108  and/or sensor assembly  80 . Power supply  118  may be integral to locking collar  72  or externally coupled to locking collar  72 . 
     Locking collar  72 , e.g., electronic circuitry  108 , may include one or more processors and one or more computer-readable media, one or more communication interfaces, and one or more power sources. The communication interfaces may support both wired and wireless connection to various networks, such as cellular networks, radio, Wi-Fi networks, short range networks (e.g., Bluetooth® technology), and infrared (IR) networks, for example. 
     Depending on the configuration of electronic circuitry  108 , the computer-readable media (and other computer-readable media described throughout) is an example of computer storage media and may include volatile and nonvolatile memory. Thus, the computer-readable media may include, without limitation, RAM, ROM, EEPROM, flash memory, and/or other memory technology, and/or any other suitable medium that may be used to store computer-readable instructions, programs, applications, media items, and/or data which may be accessed by electronic circuitry  108 . The computer-readable media may be used to store any number of functional components that are executable on a processor. Electronic circuitry  108  may have additional features or functionality. For example, electronic circuitry  108  may also include additional data storage devices (removable and/or non-removable). The additional data storage media, which may reside in a control board, may include volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information, such as computer readable instructions, data structures, program modules, or other data. In addition, some or all of the functionality described as residing within electronic circuitry  108  may reside remotely from electronic circuitry  108 , e.g., in remote reception circuitry  110 , in some implementations. In these implementations, electronic circuitry  108  may utilize communication interfaces to communicate with remote reception circuitry  110  and utilize this functionality. 
       FIG.  16    illustrates an example method  200  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  202  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  202  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  204  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  204  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  206  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. 
     In an example embodiment, a method for selectably controlling a fluid flow in an obturator assembly is provided. The obturator assembly includes a catheter forming a lumen and an obturator movably positioned within the lumen between a first position and a second position. The method includes pushing a proximal end of the obturator to move the obturator within the lumen in a distal direction until a distal tip portion of the obturator extends beyond a distal end of the catheter to provide a fluid flow path. The method further includes pulling the proximal end of the obturator to move the obturator within the lumen in a proximal direction until the distal tip portion of the obturator is at least partially positioned within the lumen to close the fluid flow path. 
     Those of skill in the art will appreciate that embodiments not expressly illustrated herein may be practiced within the scope of the claims, including that features described herein for different embodiments may be combined with each other and/or with currently-known or future-developed technologies while remaining within the scope of the claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation unless specifically defined by context, usage, or other explicit designation. It is therefore intended that the foregoing detailed description be regarded as illustrative rather than limiting. And, it should be understood that the following claims, including all equivalents, are intended to define the spirit and scope of this invention. Furthermore, the advantages described above are not necessarily the only advantages of the invention, and it is not necessarily expected that all of the described advantages will be achieved with every embodiment. In the event of any inconsistent disclosure or definition from the present application conflicting with any document incorporated by reference, the disclosure or definition herein shall be deemed to prevail.