Vascular Access Devices

Abstract

The instrument configured to be inserted through a vascular access device includes a helical coil formed from a wire, the helical coil defining a central passage, and a core wire extending along a longitudinal axis of the helical coil through at least a portion of the central passage of the helical coil, at least a portion of the core wire including a flat surface extending in a direction along the longitudinal axis and a semi-cylindrical surface extending in a direction along the longitudinal axis.

Description

[Technical field]

[0001] The present disclosure relates to a vascular access system having a secondary catheter.

[0002] This application claims priority to U.S. Provisional Application No. 63 / 314,777, entitled "Vascular Access Instrument," filed February 28, 2022, the entire disclosure of which is incorporated herein by reference in its entirety. [Background technology]

[0003] Catheters are frequently used to administer fluids into and out of the body. Patients in various settings, including hospitals and home care, receive fluids, medicines, and blood products via vascular access devices inserted into the patient's vascular system. Catheters of various types and sizes are widely used in a variety of procedures, including, but not limited to, treating infections, providing anesthesia or analgesia, providing nutritional support, treating cancerous tumors, maintaining blood pressure and heart rhythm, and many other clinical applications. A common vascular access device is a plastic catheter that is inserted into a patient's vein. The length of the catheter can vary from a few centimeters for peripheral access to many centimeters for central access. Catheters are commonly incorporated into a catheter adapter to aid in the ease of use, accessibility, and usefulness of the catheter. The catheter adapter can be adapted to accommodate one end of the catheter such that one end of the catheter is supported by the catheter adapter and the body and tip of the catheter extend beyond the first end of the catheter adapter. The catheter adapter generally further includes a second end adapted to accept an additional infusion component for use with the catheter. For example, the second end of the catheter adapter may include a series of threads for attaching an intravenous line or for coupling a syringe to the catheter adapter, thereby providing access to the patient's vascular system via the attached catheter.

[0004] The catheter may be inserted percutaneously. When inserted percutaneously, insertion of the catheter is generally assisted by an introducer needle. The introducer needle is generally housed within the lumen of the catheter such that the gauge of the needle approximates the inner diameter of the catheter. The needle is positioned within the catheter such that the needle tip extends beyond the tip of the catheter, whereby the needle is used to pierce the patient's vein and provide an opening for insertion of the catheter.

[0005] To verify proper placement of the introducer needle and / or catheter within the blood vessel, the clinician will typically confirm that there is a "flashback" of blood within the flashback chamber of the catheter assembly. Once needle placement is confirmed, the clinician may temporarily occlude flow within the vasculature and remove the needle, leaving the catheter in place for subsequent blood draws, infusions or probe access.

[0006] Blood collection or transfusion using a catheter can be difficult for several reasons, especially if the catheter dwells in the patient for more than a day. For example, if the catheter is left in the patient for a long period of time, it may be more susceptible to stenosis, breakage, kinking, blockage by debris (e.g., fibrin or platelet clots), and adhesion of the catheter tip to the vasculature. For this reason, catheters are often used to collect blood samples at the time of catheterization, but much less frequently to collect blood samples during the catheter dwell period. Thus, when a blood sample is required, an additional needle stick is used to provide venous access for blood collection, which can be painful for the patient and results in higher material costs. Summary of the Invention

[0007] In one aspect or embodiment, an instrument configured to be inserted through a vascular access device includes a helical coil formed by a wire, the helical coil defining a central passage, and a core wire extending along a longitudinal axis of the helical coil through at least a portion of the central passage of the helical coil, at least a portion of the core wire including a flat surface extending in a direction along the longitudinal axis and a semi-cylindrical surface extending in a direction along the longitudinal axis.

[0008] The core wire may include a first cross-sectional shape, the first cross-sectional shape having a linear portion and a semicircular portion. The core wire may include a second cross-sectional shape, the second cross-sectional shape being circular. The first cross-sectional shape may be less than 33% of the cross-sectional area of ​​the central passage. The core wire may taper in size from the second cross-sectional shape to the first cross-sectional shape. The semi-cylindrical surface may have a radius equal to or less than the inner radius of the helical coil. The planar surface may extend along a chord of the central passage.

[0009] In one aspect or embodiment, a vascular access system includes a catheter adapter including a catheter configured to be inserted into a patient's vasculature, and an instrument advancement device coupled to the catheter adapter, the instrument advancement device including an instrument of any of the above aspects or embodiments, the instrument advancement device configured to advance the instrument from a stored position to an advanced position beyond a distal end of the catheter, a helical coil of the instrument configured to extend beyond the distal end of the catheter when the instrument is in the advanced position.

[0010] In one aspect or embodiment, an instrument configured to be inserted through a vascular access device includes a helical coil formed by a wire, the helical coil defining a central passage, and a core wire extending along a longitudinal axis of the helical coil through at least a portion of the central passage of the helical coil, the core wire including a first wire having a first diameter and a second wire having a second diameter, the first diameter being greater than the second diameter. At least a portion of the second wire extends within the central passage. The first wire is attached to the second wire to form the core wire.

[0011] The first wire and the second wire may overlap in a direction extending along the longitudinal axis. An end of the first wire may be attached to an end of the second wire. The first core may be attached to the second wire via at least one of welding, brazing, soldering, and an adhesive.

[0012] In one aspect or embodiment, an instrument configured to be inserted through a vascular access device includes a helical coil formed by a wire, the helical coil defining a central passage, and a core wire extending through at least a portion of the central passage of the helical coil along a longitudinal axis of the helical coil, at least a portion of the length of the core wire having a C-shaped cross-section.

[0013] The outer surface of the core wire can have a radius equal to or less than the inner radius of the helical coil. The core wire can include a first portion including a length of the core wire having a C-shaped cross-section and a second portion having a circular cross-section.

[0014] In one aspect or embodiment, an instrument configured to be inserted through a vascular access device includes a tubular member having a first end and a second end disposed opposite the first end, the tubular member defining a central passage and a plurality of sidewall openings in fluid communication with the central passage, the plurality of sidewall openings being disposed from the first end to the second end of the tubular member.

[0015] The instrument may include a core wire attached to a first end of the tubular member. The instrument may include a proximal member extending from and integrally formed with the tubular member, the proximal member having a continuous, uninterrupted sidewall. The tubular member may be formed from a shape memory alloy. [Brief description of the drawings]

[0016] The above and other features and advantages of the present disclosure, as well as the manner in which they are accomplished, will become more apparent, and the disclosure itself will be better understood, by reference to the following description of embodiments of the disclosure taken in conjunction with the accompanying drawings. [Figure 1A] FIG. 1A is a perspective view of a vascular access system according to one aspect or embodiment of the present invention, showing a retracted position of an instrument. [Figure 1B] FIG. 1B is a perspective view of the vascular access system of FIG. 1 showing an advanced position of the instrument. [Figure 1C] FIG. 1C is a partial perspective view of the vascular access system of FIG. 1 showing an advanced position of the instrument. [Figure 1D] FIG. 1D is a partial cross-sectional view of the vascular access system of FIG. 1 showing an advanced position of the instrument. [Figure 1E] FIG. 1E is a cross-sectional view of the vascular access system of FIG. 1 showing an advanced position of the instrument within the patient's vasculature. [Diagram 2] FIG. 2 is a perspective view of a device of the vascular access system of FIG. 1 according to one aspect or embodiment of the present invention. [Diagram 3] FIG. 3 is a cross-sectional view of the device of FIG. [Figure 4] FIG. 4 is a cross-sectional view of the device of FIG. [Diagram 5] FIG. 5 is a perspective view of an apparatus according to a further aspect or embodiment of the present invention. [Figure 6] FIG. 6 is a perspective view of an apparatus according to a further aspect or embodiment of the present invention. [Figure 7] FIG. 7 is a schematic diagram of an apparatus according to a further aspect or embodiment of the present invention. [Figure 8] FIG. 8 is a cross-sectional view of the device of FIG. [Figure 9] FIG. 9 is a partial perspective view of an apparatus according to a further aspect or embodiment of the invention showing an intermediate portion of the apparatus. [Figure 10] FIG. 10 is a partial perspective view of the device of FIG. 9 showing an end of the device. [Figure 11] FIG. 11 is a side view of an apparatus according to a further aspect or embodiment of the present invention. [Figure 12] FIG. 12 is a perspective view of the device of FIG.

[0017] Corresponding reference characters indicate corresponding parts throughout the several views. The illustrations presented herein illustrate exemplary embodiments of the present disclosure, and such illustrations are not to be construed as limiting the scope of the present disclosure in any way. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Spatial or directional terms such as "left," "right," "inner," "outer," "above," "below," etc. should not be considered limiting as the present invention may contemplate various alternative orientations.

[0019] For purposes of description hereinafter, the terms "upper", "lower", "right", "left", "vertical", "horizontal", "top", "bottom", "transverse", "vertical" and their derivatives refer to the present invention as oriented in the drawings. It will be understood, however, that the present invention may be subject to various alternative modifications unless expressly specified to the contrary. It should also be understood that the specific devices illustrated in the accompanying drawings, and described in the following specification, are merely exemplary embodiments of the present invention.

[0020] Unless otherwise indicated, all ranges or ratios disclosed herein should be understood to encompass the starting and ending values, and any and all subranges or subratios contained therein. For example, a specified range or ratio of "1 to 10" should be considered to include any and all subranges or subratios between (and including) the minimum value of 1 and the maximum value of 10, i.e., all subranges or subratios begin with a minimum value of 1 or greater and end with a maximum value of 10 or less.

[0021] The terms "first," "second," and the like are not intended to refer to any particular order or chronology, but rather to different conditions, characteristics, or elements.

[0022] As used herein, "at least one" is synonymous with "one or more." For example, the phrase "at least one of A, B, and C" means any one of A, B, or C, or any combination of any two or more of A, B, or C. For example, "at least one of A, B, and C" includes one or more A alone, or one or more B alone, or one or more C alone, or one or more A and one or more B, or one or more A and one or more C, or one or more B and one or more C, or all of A, B, and C.

[0023] 1A-4, in one aspect or embodiment, a vascular access system 10 includes a catheter assembly 12, which may include a catheter adapter 14 and a catheter 16. The catheter 16 may be a peripheral venous catheter, a peripherally inserted central catheter, or a midline catheter. In some aspects or embodiments, the catheter adapter 14 includes a distal end 18, a proximal end 20, and a lumen extending through the distal end 18 and the proximal end 20. In some aspects or embodiments, the catheter 16 extends distally from the distal end 18 of the catheter adapter 14. The catheter adapter 14 may be integrated with an extension tube 22, which may extend from a side port 24 of the catheter adapter 14. In some aspects or embodiments, an adapter 26, such as, for example, a Y adapter or a T adapter, may be coupled to the proximal end of the extension tube 22. An instrument advancement device 28 may be coupled to the catheter assembly 12 in a variety of ways. In one aspect or embodiment, the instrument advancement device 28 is coupled to a port of the adapter 26. In one aspect or embodiment, the instrument advancing device 28 is coupled to a needleless connector 29 disposed between a port of the adapter 26 and the instrument advancing device 28. The instrument advancing device 28 may also be coupled to the proximal end 20 of the catheter adapter 14. In some aspects or embodiments, another extension tube and / or a blood collection device adapter may be coupled to another port of the adapter 26. The blood collection device adapter may receive a blood collection device, such as, for example, a syringe or a blood collection tube.

[0024] The instrument advancing device 28 may include a housing 30 configured to couple to the catheter assembly 12. The instrument advancing device 28 includes an instrument 32. In some aspects or embodiments, the instrument advancing device 28 may include any suitable delivery device. Some examples of instrument advancing devices that may be used with the instrument 32 include U.S. patent application Ser. No. 16 / 037,246, filed July 17, 2018, entitled "Extension for Accommodating a Probe or Intravenous Catheter," U.S. patent application Ser. No. 16 / 38650, filed April 18, 2019, entitled "Instrument Delivery Device with Rotating Elements," U.S. patent application Ser. No. 16 / 037,319, filed July 17, 2018, entitled "MULTI-DIAMER CATHETERS AND RELATED DEVICES AND METHODS," and U.S. patent application Ser. No. 16 / 037,320, filed July 3, 2019, entitled "Delivery Device for Vascular Access Instruments." No. 502,541, entitled "SYRINGE-BASED DELIVERY DEVICE FOR VASCULAR ACCESS DEVICES," U.S. patent application Ser. No. 16 / 691,217, filed Nov. 21, 2019, entitled "CATHETER DELIVERY DEVICE AND RELATED SYSTEMS AND METHODS," U.S. patent application Ser. No. 62 / 794,437, filed Jan. 18, 2019, entitled "CATHETER DELIVERY DEVICE AND RELATED SYSTEMS AND METHODS," and U.S. patent application Ser. No. 62 / 830,286, filed Apr. 5, 2019, entitled "VASCULAR ACCESS DEVICES HAVING FLUID-PERMEABLE STRUCTURES, AND RELATED DEVICES AND METHODS," each of which is incorporated by reference in its entirety.

[0025] In some aspects or embodiments, the instrument advancement device 28 may be configured to introduce the instrument 32 into the catheter assembly 12. As shown in FIG. 1E, in response to the instrument 32 being introduced into the catheter assembly 12, the instrument 32 may access a fluid path of the catheter assembly 12 and / or the instrument 32 may extend through the catheter assembly 12 to access the patient's vasculature. The instrument advancement device 28 may be configured to advance the instrument 32 between a stored position, e.g., as shown in FIG. 1A, and an advanced position, e.g., as shown in FIG. 1B. In some aspects or embodiments, the distal tip 34 of the instrument 32 may be disposed distal to the distal end 36 of the catheter 16 in response to the instrument 32 being in the advanced position. In some aspects or embodiments, in response to the instrument 32 being in the stored position, the distal tip 34 of the instrument 32 may be disposed within the housing 30. The proximal end of the instrument 32 may be coupled to an advancement tab 38 that may be grasped and moved along a slot 40 by a user to move the instrument 32 between the retracted position and the advanced position. The advancement tab 38 may extend through the slot 40, and the portion of the advancement tab 38 coupled to the proximal end of the instrument 32 may fit within the housing 30.

[0026] In some aspects or embodiments, the catheter 16 may be constructed of fluorinated ethylene propylene, TEFLON™, silicone, thermoplastic elastomers, thermoplastic polyurethanes, fluorinated polymers, hydrophilic materials, hydrophobic materials, anti-fouling materials, or another suitable material. In some aspects or embodiments, the catheter 16 may include an anti-thrombogenic coating. In some embodiments, all or a portion of the instrument 32 may be constructed of metal or another suitable material. In some aspects or embodiments, the distal end 36 of the catheter 16 may be symmetrical or asymmetrical.

[0027] 1C-1E, in some embodiments, the device 32 may include a helical coil 42 formed into multiple loops 46 by wire wound around an axis 44. The wire may be of various cross-sectional shapes, including flat, round, oval, half-round, and the like. In some aspects or embodiments, the helical coil 42 may be constructed of metal or other suitable material. In some aspects or embodiments, the helical coil 42 may be disposed at the distal end of the device 32 and / or adjacent the distal tip 34. In some aspects or embodiments, each of the loops 46 of the helical coil 42 may be spaced apart from the next adjacent loop of the loop 46, which may promote fluid permeability of the distal end of the device 32. The helical coil 42 may provide multiple fluid pathways along the length of the device 32, which may facilitate the inflow of blood from a portion of the vasculature more distal from the catheter 16 into the catheter assembly 12. In some aspects or embodiments, the fluid pathways along the length of the instrument 32 and the helical coil 42 may facilitate increased fluid flow rates through the instrument 32 and the catheter 16. In some aspects or embodiments, the fluid pathways along the length of the instrument 32 and the helical coil 42 may facilitate reduced blood draw times. In some aspects or embodiments, the helical coil 42 may reduce shear stress and associated risks of hemolysis of blood in and / or through the catheter 16. In some aspects or embodiments, the helical coil 42 may facilitate soft, gentle contact with the walls of the vasculature in response to insertion of the instrument 32 into the vasculature. In one aspect or embodiment, the instrument 32 includes a core wire 48 extending through at least a portion of the helical coil 42.

[0028] In some aspects or embodiments, the wire may include a first side 50 and a second side 52 opposite and parallel to the first side 50 before the wire is wound into loops 46 around axis 44 during manufacture. The first side 50 forms an outer surface of the helical coil 42. The second side 52 forms an inner surface of the helical coil 42. The core wire 48 may be coupled to the inner surface of the helical coil 42. In some aspects or embodiments, the wire may increase the inner diameter of the helical coil 42 to facilitate increased fluid flow through the device 32. The wire may increase the inner diameter of the helical coil 42 and may allow the outer diameter of the helical coil 42 to be the same length as the outer diameter of a standard vascular access device.

[0029] 1D , the distal end 36 of the catheter 16 includes a distal opening 53. In some aspects or embodiments, the coil 42 may extend through the distal opening 53 of the catheter 16 in response to the instrument 32 being in an advanced position. The outer diameter of the helical coil 42 may be smaller than the diameter of the distal opening 53, which may create a gap through which fluid can flow. The distal end 36 of the catheter 16 may include one or more diffuser holes 54 that may be aligned with a portion of the instrument 32 that includes the coil 42 to facilitate blood flow into the catheter assembly 12 and / or fluid infusion into the vasculature.

[0030] In some aspects or embodiments, the dimensions of the helical coil 42 may vary based on the gauge size of the catheter 16, the stiffness of the device 32, the spacing between each of the loops 46 of the helical coil 42, the number or size of the fluid paths along the length of the device 32, or another factor.

[0031] In some aspects or embodiments, the distal tip 34 may be rounded or blunt, which may prevent damage to the vasculature. The distal tip 34 may be disposed at the distal end of the core wire 48 and / or may be integrally formed with the distal end of the core wire 48 as a single unit. Additionally or alternatively, in some embodiments, the distal tip 34 may be coupled to the distal end of the helical coil 42.

[0032] In some aspects or embodiments, distal tip 34 may be rounded or blunt. Distal tip 34 may be disposed at the distal end of elongated strip 55 and / or may be integrally formed with the distal end of elongated strip 55 as a single unit. Additionally or alternatively, in some aspects or embodiments, distal tip 34 may be coupled to the distal end of helical coil 42.

[0033] 2-4, in one aspect or embodiment, the core wire 48 extends along the longitudinal axis 60 of the helical coil 42 through at least a portion of the central passage 62 of the helical coil 42, and at least a portion of the core wire 48 includes a flat surface 64 extending in a direction along the longitudinal axis 60 and a semi-cylindrical surface 66 extending in a direction along the longitudinal axis 60. As shown in FIG. 4, the core wire 48 can include a first cross-sectional shape, the first cross-sectional shape having a linear portion 68 and a semi-circular portion 70. As shown in FIG. 3, the core wire 48 has a second cross-sectional shape. The second cross-sectional shape is circular. The first cross-sectional shape is less than 33% of the cross-sectional area of ​​the central passage 62. As shown in FIG. 2, the core wire 48 tapers in size from the second cross-sectional shape to the first cross-sectional shape. In certain aspects or embodiments, the radius of the semi-cylindrical surface 66 is equal to or less than the inner radius of the helical coil 42, and the plane 64 extends along a chord of the central passage 62. In one aspect or embodiment, the length of the linear portion 68 is less than the diameter of the central passage 62. In one aspect or embodiment, the first cross-sectional shape is D-shaped. The plane 64 of the core wire 48 may be formed by grinding one side of a round wire or by skiving a round wire. The plane 64 of the core wire 48 is configured to increase flexibility of at least a portion of the instrument 32 while ensuring that a sufficient portion of the central passage 62 remains open to maximize fluid flow therethrough.

[0034] 5 and 6, in a further aspect or embodiment, the core wire 48 includes a first wire 80 having a first diameter and a second wire 82 having a second diameter, the first diameter being greater than the second diameter. At least a portion of the second wire 82 extends into the central passage 62 with the first wire 80 attached to the second wire 82 to form the core wire 48. As shown in FIG. 6, in one aspect or embodiment, the first wire 80 and the second wire 82 overlap in a direction extending along the longitudinal axis 60. As shown in FIG. 5, in one aspect or embodiment, an end of the first wire 80 is attached to an end of the second wire 82. The first wire 80 may be attached to the second wire 82 via at least one of welding, brazing, soldering, and adhesives. In some aspects or embodiments, core wire 48 includes a connection 84, such as an adhesive connection, configured to hold second wire 82 to the side of helical coil 42. For clarity, connection 84 is shown as being larger in diameter than first wire 80 and second wire 82, but connection 84 may be the same diameter as or smaller than the diameter of first wire 80.

[0035] 7 and 8, in a further aspect or embodiment, at least a portion of the length of core wire 48 has a C-shaped cross-section. An outer surface 90 of core wire 48 can have a radius equal to or less than the inner radius of helical coil 42. Core wire 48 can include a first portion 92 that includes the length of core wire 48 having a C-shaped cross-section and a second portion 94 that has a circular cross-section. The C-shaped cross-section provides rigidity and support for insertion of instruments while maintaining sufficient area within central passageway 62 and maximizes fluid flow through central passageway 62.

[0036] With reference to Figures 9-12, an instrument 100 according to a further aspect or embodiment of the present application is shown. The instrument 100 may generally function in the same manner as the instrument 32 described above. Instead of providing a helical coil 42, the instrument 100 includes a tubular member 102 having a first end 104 and a second end 106 disposed opposite the first end 104, the tubular member 102 defining a central passageway 108 and a plurality of sidewall openings 110 in fluid communication with the central passageway 108. The plurality of sidewall openings 110 are disposed from the first end 104 to the second end 106 of the tubular member 102. The fluid pathway of the instrument 100 of Figures 9-12 may be contained within the tubular member 102, rather than being allowed to flow outside the catheter lumen, as shown in Figure 1E. The sidewall openings 110 may be only distal to the catheter tip or may be both distal and proximal to the catheter tip to reduce the possibility of mixing and / or contamination of fluids from within the catheter. In this manner, a pathway to a blood collection device such as the instrument advancing device 28 can be provided, such as a pathway that extends through the instrument advancing device 28 rather than through the adapter 26.

[0037] In one aspect or embodiment, as shown in Figure 9, a core wire 112 is attached to the first end 104 of the tubular member 102. In one aspect or embodiment, as shown in Figure 11, rather than providing a core wire 112, the instrument 100 includes a proximal member 114 extending from and integrally formed with the tubular member 102, the proximal member 114 having a continuous, uninterrupted sidewall 116.

[0038] In one aspect or embodiment, the tubular member 102 is formed from a shape memory alloy. The sidewall openings 110 may be laser cut or otherwise formed in the tubular member 102. The tubular member 102 is configured to retain an outer diameter and an inner diameter without the use of a core wire disposed within the tubular member 102, which increases the size of the flow passage through the central passage 108 to improve fluid flow therethrough. In one aspect or embodiment, the tubular member 102 is formed from a polymeric material. The location and size of the sidewall openings 110 may be adjusted to improve manufacturability or increase flexibility in a portion of the tubular member 102, such as the distal tip 118, by increasing the size or frequency of the sidewall openings 110. In one aspect or embodiment, the shape or direction of access of the sidewall openings 110 is configured to increase flexibility in a portion of the tubular member 102. For example, the sidewall openings 110 may be formed from one side or in an intermittent spiral pattern. In one aspect or embodiment, the multiple sidewall openings 110 are configured to improve thrombus passage prevention by having smaller holes near the distal tip 118 of the device 100 or by providing smaller openings 110 at the proximal end of each opening 110. In one aspect or embodiment, the device 100 is formed from metal and configured to pass electrical signals to enable communication with a sensor (not shown). The tubular member 102 may be configured to inhibit mixing and contamination in the catheter assembly 12 and the joints.

[0039] While the present invention has been described in detail for purposes of illustration based on what are currently considered to be the most practical and preferred embodiments or aspects, it is to be understood that such detail is for this purpose only, and that the present invention is not limited to the disclosed embodiments or aspects, but on the contrary, is intended to cover modifications and equivalent arrangements within the spirit and scope of the appended claims. For example, it is to be understood that the present invention contemplates that, to the extent possible, one or more features of any embodiment may be combined with one or more features of any other embodiment.

Claims

1. 1. An instrument configured to be inserted through a vascular access device, comprising: a helical coil formed from wire, the helical coil defining a central passage; a core wire extending through at least a portion of the central passage of the helical coil along a longitudinal axis of the helical coil, at least a portion of the core wire comprising a flat surface extending in a direction along the longitudinal axis and a semi-cylindrical surface extending in a direction along the longitudinal axis.

2. The instrument of claim 1 , wherein the core wire includes a first cross-sectional shape, the first cross-sectional shape having a linear portion and a semicircular portion.

3. The instrument of claim 2 , wherein the core wire includes a second cross-sectional shape, the second cross-sectional shape being circular.

4. The instrument of claim 2 , wherein the first cross-sectional shape is less than 33% of a cross-sectional area of ​​the central passageway.

5. The device of claim 3 , wherein the core wire tapers in size from the second cross-sectional shape to the first cross-sectional shape.

6. The device of claim 1 , wherein the semi-cylindrical surface has a radius less than or equal to an inner radius of the helical coil.

7. The device of claim 6 , wherein the plane extends along a chord of the central passage.

8. 1. A vascular access system comprising: a catheter adapter including a catheter configured to be inserted into the vascular system of a patient; an instrument advancement device coupled to the catheter adapter, the instrument advancement device including a helical coil formed by a wire, the helical coil defining a central passage, and a core wire extending along a longitudinal axis of the helical coil through at least a portion of the central passage of the helical coil, at least a portion of the core wire comprising a flat surface extending in a direction along the longitudinal axis and a semi-cylindrical surface extending in a direction along the longitudinal axis; Including, A vascular access system, wherein the instrument advancement device is configured to advance the instrument from a stored position to an advanced position over a distal end of the catheter, and the helical coil of the instrument is configured to extend beyond the distal end of the catheter when the instrument is in the advanced position.

9. 1. An instrument configured to be inserted through a vascular access device, comprising: a helical coil formed from wire, the helical coil defining a central passage; a core wire extending along a longitudinal axis of the helical coil through at least a portion of the central passage of the helical coil, the core wire including a first wire having a first diameter and a second wire having a second diameter, the first diameter being greater than the second diameter, at least a portion of the second wire extending into the central passage, the first wire being attached to the second wire to form the core wire; Including, fixtures.

10. The device of claim 9 , wherein the first wire and the second wire overlap in a direction extending along the longitudinal axis.

11. The device of claim 9 , wherein an end of the first wire is attached to an end of the second wire.

12. The apparatus of claim 10 , wherein the first wire is attached to the second wire via at least one of welding, brazing, soldering, and an adhesive.

13. 1. An instrument configured to be inserted through a vascular access device, comprising: a helical coil formed from wire, the helical coil defining a central passage; a core wire extending through at least a portion of the central passage of the helical coil along a longitudinal axis of the helical coil, the core wire having a C-shaped cross-section along at least a portion of its length; An apparatus comprising:

14. The device of claim 13 , wherein an outer surface of the core wire has a radius less than or equal to an inner radius of the helical coil.

15. 14. The device of claim 13, wherein the core wire comprises a first portion having the C-shaped cross-section including the length of the core wire and a second portion having a circular cross-section.

16. 1. An instrument configured to be inserted through a vascular access device, comprising: a tubular member having a first end and a second end disposed opposite the first end, the tubular member defining a central passage and a plurality of sidewall openings in fluid communication with the central passage, the plurality of sidewall openings being disposed from the first end to the second end of the tubular member; An apparatus comprising:

17. The apparatus of claim 16, further comprising a core wire attached to the first end of the tubular member.

18. The instrument of claim 16, further comprising a proximal member extending from and integrally formed with said tubular member, said proximal member having a continuous, uninterrupted sidewall.

19. The instrument of claim 16 , wherein the tubular member is formed from a shape memory alloy.

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