Vascular access catheter

Abstract

A vascular access catheter includes an elongated tubular catheter body enclosing an internal lumen. The catheter body includes a catheter tip ending with a catheter distal end and including a distal rim at the catheter distal end that encircles an opening open to the internal lumen. The distal rim includes a front rim portion spanning a top portion of the opening and a beveled rim portion spanning a bottom portion of the opening and beveled proximally away from the front rim portion relative to a longitudinal axis of the catheter body. The vascular access catheter can be provided in a vascular access kit that also includes an access needle having a hollow needle body and a beveled tip ending with a sharp needle rim.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 030,410, filed May 27, 2020, entitled “OVER-THE-NEEDLE CATHETER,” the entire contents of which are hereby incorporated by reference. Technical Field

[0003] This disclosure relates to apparatus and methods for accessing blood vessels, and more specifically, but not exclusively, to apparatus and methods for inserting a catheter into a blood vessel above an access needle. Background Technology

[0004] Peripherally intravenous (PIV) catheterization is an invasive hospital procedure for administering medications or other fluids, typically involving inserting a needle into a peripheral vein, followed by the introduction of a catheter over the needle. For fluid administration, the needle is withdrawn, leaving at least the catheter tip and opening open for fluid delivery. PIV catheterization traditionally involves a considerable failure rate, indicated by the removal of the catheter from the vein before its intended stay has ended. Common causes of failure include “infiltration” and “occlusion,” in which the catheter and / or needle penetrate a portion of the vein wall (opposite to the point of entry into the vein), and in which occlusion results from thrombosis in the catheter or the vein itself, optionally leading to loss of infusion capacity due to infiltration and phlebitis (phlebitis). Summary of the Invention

[0005] This disclosure relates to apparatus and methods for accessing blood vessels, and more specifically, but not exclusively, to apparatus and methods for inserting a catheter into a blood vessel above an access needle.

[0006] In some embodiments, a vascular access catheter is provided, comprising an elongated tubular catheter body that encloses an inner lumen. The catheter body includes a catheter tip that terminates at a distal end and includes a distal edge at the distal end that surrounds an opening to the inner lumen. The distal edge includes a leading edge portion and a sloping edge portion that crosses a top portion of the opening and crosses a bottom portion of the opening and slopes proximally away from the leading edge portion relative to the longitudinal axis of the catheter body.

[0007] In some embodiments, the lumen is cylindrical along the portion of the catheter body proximal to the catheter tip and tapers towards the catheter tip.

[0008] In some embodiments, the leading edge portion substantially coincides with the transverse plane of the catheter body that spans perpendicularly to the longitudinal axis. In some embodiments, the leading edge portion is parallel to the transverse plane and spans at least half of the cross-section of the catheter body at its distal end. In some embodiments, the inclined edge portion is inclined with an average angle of less than 45° about the transverse plane or the leading edge portion.

[0009] In some embodiments, the front edge portion is at least partially flat. In some embodiments, the sloping edge portion is at least partially curved.

[0010] In some embodiments, the radius of curvature of the sloping edge portion is smallest near the front edge portion and / or largest near the vertex of the sloping edge portion. In some embodiments, the radius of curvature of the sloping edge portion gradually increases between the front edge portion and the vertex of the sloping edge portion.

[0011] In some embodiments, the inclined edge portion includes or is merged with a sliding surface, the sliding surface being at least partially parallel to the inclined edge portion and / or the longitudinal axis, or inclined at a shallow angle with respect to the inclined edge portion and / or the longitudinal axis. In some embodiments, the sliding surface forms a shaped region bounded by a distal parabola and a proximal parabola and between the distal and proximal parabolas, the distal parabola having a focal length smaller than that of the proximal parabola. In some embodiments, the sliding surface is at least partially curved. In some embodiments, the catheter tip varies in thickness along the sliding surface. In some embodiments, the sliding surface has an average radius of curvature significantly larger than the radius of the outer surface portion of the catheter tip opposite the sliding plane in a common transverse section.

[0012] In some embodiments, the inclined edge portion includes two curved surfaces located on opposite sides of the opening relative to the longitudinal axis, each of the sliding surfaces clearly merging with the front edge portion at a different merging portion.

[0013] In some embodiments, the catheter is configured to engage the inner surface of the blood vessel with the sloping edge portion when pushed over the entry needle, and is configured to slide distally on the inner surface of the blood vessel using the sloping edge portion when the entry needle is withdrawn from the catheter tip and the catheter tip is pressed against the blood vessel wall.

[0014] In some embodiments, the front edge portion merges with the sloping edge portion at the merging portion, wherein the merging portion is rounded, curved, and / or sloping.

[0015] In some embodiments, the merging portion is positioned adjacent to or below the longitudinal axis.

[0016] In some embodiments, the catheter tip includes a groove extending along the bottom end of the catheter tip, extending proximally from and opening onto the sloping edge portion. In some embodiments, the catheter tip includes a narrow incision or slit extending along the bottom end of the catheter tip, extending proximally from and opening onto the sloping edge portion.

[0017] In some embodiments, the sloping edge portion near its apex forms a first tangential angle with the longitudinal axis, which is less than approximately 20°. In some embodiments, the sloping edge portion near the front edge portion forms a second tangential angle with the longitudinal axis, which is greater than approximately 45°.

[0018] In some embodiments, the bottom end of the catheter tip has an elastic resistance to inward radial deformation that is less than the elastic resistance to inward radial deformation of the top end of the catheter tip. In some embodiments, when not supported internally by an entry needle, the catheter tip is configured to collapse radially inward when the bottom end of the catheter tip is pressed against the vessel wall at an angle, and when the catheter body transmits a force to the vessel wall that is insufficient to cause mechanical damage to it.

[0019] In some embodiments, the catheter is configured such that when it collapses radially inward, the catheter tip has a footprint on the surface of the vessel wall along its bottom end, which is larger in size than the cross-section of the maximum size of the insertion needle.

[0020] In some embodiments, a vascular access kit is provided, comprising a vascular access catheter and an access needle, the access needle comprising a hollow needle body and a beveled end ending with a distal sharp needle edge. In some embodiments, the catheter is configured to receive the access needle through a lumen and an opening in at least two configurations, including a tissue-penetrating configuration and a safety configuration, in which the beveled end extends fully distal to the lumen at the distal end of the catheter, and in which the beveled end remains fully residing within the lumen proximal to the distal end of the catheter.

[0021] In some embodiments, the lumen decreases in diameter along the catheter tip to a sealing diameter smaller than the diameter of the entry needle proximal to the beveled tip, so that a seal is formed around the entry needle in a tissue penetration configuration to prevent blood from entering the lumen through the opening, and in a secure configuration to allow blood to enter the lumen through the opening.

[0022] In some embodiments, the kit includes a coupling device configured to secure the entry needle in the catheter during tissue penetration.

[0023] In some embodiments, when in a tissue-penetrating configuration, the needle edge has an equal or greater distance to the vertex of the inclined edge portion compared to the distance to the vertex of the leading edge portion.

[0024] In some embodiments, the kit is configured such that when it collapses radially inward, the catheter tip has a footprint on the surface of the vessel wall along its bottom end that is larger in size than the maximum size of damage that can be created in the vessel wall by the insertion needle.

[0025] In some embodiments, a method is provided for inserting a catheter into a blood vessel using a kit, the method comprising: inserting a catheter tip into the blood vessel while the catheter and entry needle are in a tissue-penetrating configuration; converting the catheter and entry needle to a safe configuration by moving a beveled end relative to the catheter tip such that the beveled end is fully residing within the lumen proximal to the distal end of the catheter; engaging the inner surface of the blood vessel with the beveled edge portion; removing the entry needle from the lumen; and advancing the catheter distally within the blood vessel.

[0026] In some embodiments, insertion includes forming a lesion by using a beveled end to pass through the inner surface of the vessel wall, wherein engagement includes sliding a beveled edge portion over a distal portion of the inner surface from the opposite side of the lesion, and wherein advancement includes sliding the beveled edge portion and / or the catheter tip along its bottom end over and across the lesion.

[0027] In some embodiments, insertion includes and / or follows verification of whether blood is drawn from the vessel into the insertion needle. In some embodiments, if verification results in invalid blood drawing into the insertion needle, a switch is followed by catheter withdrawal until verification of blood drawing from the vessel into the lumen is performed. In some such embodiments, withdrawal follows a switch or removal and precedes engagement.

[0028] In some embodiments, the engagement follows the verification of blood being drawn from the blood vessel into the lumen after the conversion.

[0029] In some embodiments, insertion includes: verifying that the catheter is secured to the entry needle in a tissue-penetrating configuration; and penetrating a blood vessel with a beveled end to allow blood to be drawn from the vessel into the entry needle. In some embodiments, insertion includes verifying that the bottom portion is aligned with the blood vessel guide and / or the top portion is away from the blood vessel guide.

[0030] In some embodiments, insertion includes and / or follows verification that the blood vessel is diseased and / or a vein that is equal to or smaller than the diameter of the catheter body, or equal to or smaller than about 1 mm.

[0031] All technical and / or scientific terms, expressions and / or phrases used herein have the same or similar meanings as commonly understood by one of ordinary skill in the art to which this invention pertains, unless otherwise specifically defined or described herein. Illustrative embodiments of methods (steps, procedures), apparatus (devices, systems, components thereof), equipment, and materials described herein are merely exemplary and illustrative and are not intended to be necessarily limiting. Although methods, apparatus, equipment, and materials equivalent to or similar to those described herein may be used in practice and / or testing of embodiments of the invention, exemplary methods, apparatus, equipment, and materials are described illustratively below. In case of conflict, the patent specification (including definitions) shall prevail. Attached Figure Description

[0032] Some embodiments are described herein by way of example only, with reference to the accompanying drawings. Reference will now be made specifically and in detail to the drawings, with emphasis placed on the fact that the details shown are by way of example and for the purpose of illustrative description of some embodiments. In this regard, the description taken in conjunction with the drawings will make it apparent to those skilled in the art how some embodiments can be practiced.

[0033] In the attached diagram:

[0034] Figures 1A-1B illustrate exemplary over-the-needle catheters according to some embodiments;

[0035] Figure 2A-2C An exemplary scenario illustrating steps in a method of representation according to some embodiments is shown, the method being used to insert an exemplary catheter over a needle into a blood vessel;

[0036] Figures 3A-3D A schematic view of a first exemplary end of a needle-covering catheter according to some embodiments is shown;

[0037] Figures 4A-4B A schematic view of a second exemplary end of a needle-covering catheter according to some embodiments is shown; and

[0038] Figures 5A-5E A schematic view of a third exemplary end of a needle-covering catheter according to some embodiments is shown;

[0039] Figures 6A-6C A view showing an exemplary vascular access kit according to some embodiments;

[0040] Figures 7A-7C Illustrations based on some embodiments Figure 6A The image shows an exemplary view of a blood vessel entry catheter for the kit.

[0041] Figures 8A-8EThe illustration schematically shows a first set of exemplary scenarios of steps in a representation method according to some embodiments, the method being used to... Figure 6A The kit shown in the image enters the blood vessel; and

[0042] Figures 9A-9F The second set of exemplary scenarios schematically illustrates steps in a representation method according to some embodiments, the method being used to... Figure 6A The kit shown in the image is inserted into the blood vessel. Detailed Implementation

[0043] Some embodiments relate to means and methods for accessing blood vessels, and more specifically, but not exclusively, to means and methods for inserting a catheter into a blood vessel above an access needle.

[0044] In some embodiments, the catheter has a distal edge terminating over a top portion of the catheter tip in contrast to a bottom portion of the catheter tip. This distal edge possesses different structural and / or functional characteristics such that, under the same forces and conditions, when the catheter tip is not internally supported by a needle, it is configured to interact differently with the inner wall surface of the blood vessel compared to when the vessel wall is engaged with the top portion of the catheter tip, and when the vessel wall is engaged with the bottom portion of the catheter tip. In some embodiments, near the distal edge, the bottom portion of the catheter tip is configured and / or shaped differently from the top portion of the catheter tip. In some such or other embodiments, the distal edge is shaped differently closer to the bottom portion than the top portion of the catheter tip.

[0045] Figures 1A-1B illustrate an exemplary overcoated catheter 100, configured, for example, as a peripheral intravenous catheter. The catheter 100 includes an elongated catheter body 101, which terminates at a catheter tip 102 and is connected to a catheter handle portion 103 via its proximal end. The handle portion 103 includes wings 104 configured for manual handling and / or for securing the catheter to a patient's body, such as by using adhesive. The handle portion 103 may also optionally include a syringe connector 105 configured for connection to a syringe for facilitating the injection of a fluid (e.g., a medication).

[0046] The catheter 100 may be housed in a kit for peripheral intravenous access that also includes an entry needle 107. As shown, the needle 107 is configured to extend through the lumen of the catheter body 101, and its tip 108 is configured to protrude fully distally from the catheter tip 102 when the entry needle 107 has fully extended through and been properly secured to the handle portion 103, and is oriented (rotatably) relative to the handle portion 103 using the needle securing and / or directional member 109. Attached to the proximal end of the entry needle 107 is a wire connector 106 configured for connection to a syringe and / or optionally to an intravenous infusion line. The needle 107 may be partially or completely withdrawn (in the proximal direction) relative to the catheter tip 102 after disengagement from the handle portion 103 and pull of the entry needle 107 using the needle wings 110.

[0047] like Figure 1B As shown, the catheter tip 102 has a distal edge 111 between a top portion 112 and a bottom portion 113 of the catheter tip 102, wherein the distal edge 111 defines a shape and / or is configured to be adjacent to the bottom portion 113 differently than to the top portion 112.

[0048] In some embodiments, the catheter may be inserted into the blood vessel using one or more of the following steps (not necessarily in the same order):

[0049] >Verification: The catheter is properly positioned such that the outer surface of the bottom portion of the catheter tip faces the vascular guide, and / or the outer surface of the top portion of the catheter tip is away from the vascular guide;

[0050] Insert the entry needle into the blood vessel until blood enters the entry needle and can be seen in an optional flashback chamber, which may be provided with the kit or integrated into the catheter or a portion thereof;

[0051] > Push the insertion needle with the catheter toward the inner surface of the blood vessel wall (e.g., the deeper surface), or push the catheter over the insertion needle while the catheter tip is internally supported by the insertion needle;

[0052] >Move the catheter body relative to the insertion needle so that the end of the catheter is no longer supported internally by the insertion needle (which usually results in blood becoming visible on the inside of the catheter between the catheter tube and the needle);

[0053] The inner surface is joined to the bottom portion of the catheter tip and / or to the distal edge near the bottom portion; and

[0054] >The catheter is slid on the inner surface by advancing it distally into the blood vessel.

[0055] Figure 2A-2CAn exemplary scenario illustrating the steps of a method for inserting a catheter 100 into a blood vessel BV above an entry needle 107 is shown schematically. Figure 2A This illustrates a first scenario after catheter 100 has penetrated into blood vessel BV. A sharp needle tip 108 is applied to penetrate through the outer (e.g., shallower) wall portion SW of the skin and blood vessel BV, wherein catheter tip 102 wraps around needle 107 and is located proximal to needle tip 108. Figure 2B An optional second scenario is shown, in which the catheter tip 102 is advanced together with or over the entry needle 107 until it engages the inner (e.g., deeper) wall portion IW of the vessel BV, which is generally opposite the outer wall portion SW. Figure 2C The third scenario is shown, in which the needle 107 is partially or completely withdrawn relative to the catheter tip 102, and the latter is further advanced distally in the vessel BV, while optionally flexing and / or sliding over the inner wall portion IW.

[0056] A common failure involved in the initial needle and catheter penetration into a blood vessel (especially a small vessel) is the formation of an unintended incision or injury by the needle tip on the inner wall portion (IW) of the vessel's blood vessel wall (BV), such as injury to the LS (in...). Figure 2C (As shown in the diagram). In such cases, when a conventional catheter tip is advanced forward (distally) over a needle similar to the entry needle 107, it has a considerable potential to further damage the vessel BV (such as by enlarging or splitting the LS) and / or to penetrate through the lumen of the vessel BV by damaging the LS. Therefore, in some embodiments, the catheter tip 102 is configured to engage the inner wall portion IW immediately after penetration into the vessel BV to reduce the likelihood of contact with possible damage (such as damage to the LS) that could be formed on the inner wall IW by the needle tip 108, the inner wall portion IW being sufficiently far (e.g., distally) from the initial trajectory of the entry needle 107 (which is aligned with the longitudinal axis 114 of the needle). In some such or other embodiments, the catheter tip 102 is configured with a curved bottom portion of the distal edge 111 and / or a bottom portion configured for inward collapse to increase the footprint on the inner wall IW, which is sufficiently larger than the size of the damage to the LS, thereby reducing the likelihood that it will penetrate through the damage. In some such or other embodiments, when the catheter tip 102 is not at least partially supported by the needle 107, such as when the needle tip 108 is partially or completely (proximal) withdrawn relative to the catheter tip 102, the catheter tip 102 is configured to flex forward (e.g., distally) relative to the needle axis 114, for example, as... Figure 2C As shown in the image.

[0057] Figures 3A-3C A view schematically illustrating a first exemplary configuration of the catheter tip 102 in an elastically relaxed (stress-free) state according to some embodiments. Figure 3AAn isometric view of the catheter tip 102 is shown. Figure 3B A front view of the catheter tip 102 is shown, and Figure 3C A bottom view of the catheter tip 102 is shown. As previously described, the catheter tip 102 includes a bottom portion 113 that faces the top portion 112 around a distal edge 111. The distal edge 111 optionally includes at least one sloping edge portion, which is optionally configured as a curved and / or beveled sloping edge portion 115, the curved and / or beveled sloping edge portion 115 being inclined between a more distally protruding portion of the distal edge 111 and a less distally protruding portion of the distal edge, the less distally protruding portion being closer to the bottom portion 113 than the more distally protruding portion. The distal edge 111 may taper at least in its portion to facilitate penetration through the skin and outer wall SW of the blood vessel when pushed forward using the insertion needle 107.

[0058] The bottom portion 113 is configured to engage the vessel wall before the top portion 112 when the catheter body 101 is tilted relative to the vessel wall. In some embodiments, the bottom portion 113 has an elastic resistance to inward radial deformation that is less than the equivalent resistance of the top portion 112 and / or other portions of the catheter tip 102 adjacent to the bottom portion 113.

[0059] As a result of this design, when not supported internally by the insertion needle 107, the catheter tip 102 is configured to collapse radially inward (e.g., flex, compress, or flex, for example) when the base portion 113 is pressed against the vessel wall at an angle, and when the catheter body 101 transmits a force to the vessel wall insufficient to cause mechanical damage to it. Upon collapse, the base portion 113 has a footprint on the surface of the vessel wall (i.e., the contact area during or immediately after collapse) that is larger in size than the maximum size of damage that can be inflicted on the vessel wall by the insertion needle. Since this maximum size of the needle that inflicts damage on the vessel wall is typically approximately the size of the cross-section of the needle tip 108, or smaller, the catheter tip 102 can be designed and constructed with a minimum footprint (under the same reasonable forces and conditions) that is larger in size than the maximum size of the cross-section of the insertion needle 107.

[0060] Although configured to collapse when pressed using the base portion 113, the catheter tip 102 is configured to maintain a generally circular (or another generally rounded) cross-section when the same force is transmitted to the vessel wall when the tip portion 112 is pressed at an angle against the injury. In any case, the catheter tip is configured to elastically restore its nominally circular (or another generally rounded) cross-section when the radially inwardly collapsed base portion 113 is released from the applied force and returns to an elastically relaxed (stress-free) state. Unlike the described difference in elastic resistance to radial compression, the base portion 113 may optionally have elastic resistance to axial compression, which is similar to the elastic resistance to axial compression of the tip portion 112.

[0061] Possible methods for achieving the structural and / or functional configuration (which causes the difference in elastic resistance to radial compression between the top portion 112 and the bottom location 113 of the catheter tip 102) may include different mechanical, thermal, and / or chemical treatments with respect to each of these portions, such as using different materials, or additionally applying coatings of different types or thicknesses as known in relevant practice. For example, the bottom portion 113 may be formed separately from the top portion 112 (or the entire remainder of the catheter body 101), optionally formed from a different material than the top portion 112, or formed under a different process or treatment than the top portion 112, and later attached to the remainder of the catheter body 101, such as by using adhesives or thermal bonding.

[0062] As shown, the bottom portion 113 has at least one slit 116 extending from and opening onto the distal edge 111. The addition of the slit causes a localized reduction in the elastic resistance to radial compression, which increases closer to the slit. The slit 116 forms opposing vertical edges 117 configured to rotate inward toward the longitudinal axis 114 when the bottom portion 113 is pressed radially inward, for example, as... Figure 3D As shown in the diagram, the slit 116 is generally straight and parallel to the longitudinal axis 114 so as to maintain similar (e.g., the same) resistance to axial compression adjacent to the slit 116 (as in the top portion 112). Optionally, instead of or in combination with a slit, the bottom portion 113 has at least one weakening line extending thereal to reduce local structural resistance to radial compression relative to the top portion 112. The weakening line may optionally be configured with reduced thickness and / or reduced structural strength with respect to adjacent portions of the bottom portion 113.

[0063] Figures 4A-4B A view schematically illustrating another exemplary configuration of the catheter tip 102 according to some embodiments is shown. Figure 4A A lateral view of the catheter tip 102 is shown, and Figure 4BA bottom view of the catheter tip 102 is shown. As shown, the catheter body 101 encloses the lumen 118, and the catheter tip 102 terminates with a distal edge 111, thereby forming an opening 119 to the lumen 118 between the top portion 112 and the bottom portion 113. In this exemplary configuration, the distal edge 111 includes: a leading edge portion 120 extending substantially perpendicular to the longitudinal axis 114 from the top portion 112 toward the bottom portion 113, and at least one inclined edge portion optionally configured as an inclined edge portion 121 extending obliquely from the bottom portion 113 toward the leading edge portion 120 about the longitudinal axis 114, and merging with the leading edge portion 120 at a merging portion 122, which is optionally located below or adjacent to the longitudinal axis 114 (which coincides with the centerline of the catheter body 101).

[0064] In this regard, the catheter 100 is configured to engage the inner surface of the blood vessel (as shown in FIG. 2) with the sloping edge portion 121 when pushed over the insertion needle 107. Furthermore, the sloping edge portion 121 is configured to slide distally on the inner surface of the blood vessel when the catheter tip 102 is pressed against the vessel wall (in the case of withdrawal of the insertion needle 107). Optionally, the catheter 100 is also configured to engage the inner surface of the blood vessel with the sloping edge portion 121 proximal to the insertion needle 107.

[0065] The sloping edge portion 120 is curved and forms an angle (optionally about 20° or less) with the longitudinal axis 114 adjacent to the bottom portion 113, which is significantly smaller than the angle (optionally about 45° or greater) formed with the longitudinal axis 114 adjacent to the front edge portion 120.

[0066] The bottom portion 113 includes a groove 123 that extends proximally from and opens to the inclined edge portion 121, optionally in the form of a narrow incision, although it may additionally or alternatively include at least one slit. In some embodiments, the catheter tip 102 tapers and decreases in outer diameter and / or thickness toward the distal edge 111 to facilitate catheter penetration into the skin and to a blood vessel.

[0067] Reference Figures 5A-5E , Figures 5A-5E A view schematically illustrating a third exemplary configuration of end 102 according to some embodiments is shown. Figure 5A and Figure 5B The lateral and top views of the catheter tip 102 are shown respectively; Figure 5C An axonometric projection view of the anterior (distal) portion of the catheter tip 102 is shown; Figure 5D A side view of the catheter tip 102 is shown, which is appropriately positioned above the entry needle 107 for penetration into a blood vessel (e.g., a vein); and Figure 5E for Figure 5D An enlarged view of segment “S5E”. Similar to the previous example, catheter 100 includes an elongated tubular catheter body 101 that encloses an inner lumen 118, which extends along and for its length along a longitudinal axis 114. The catheter is configured to pass over an entry needle (e.g., needle 107) into a blood vessel. Catheter body 101 includes a catheter tip 102 that terminates at a distal edge 111, thereby forming an opening 119 to the inner lumen 118 between a top portion 112 and a bottom portion 113.

[0068] In this exemplary configuration, the distal edge 111 includes a leading edge portion 120 extending from the top portion 112 toward the bottom portion 113, which is generally perpendicular to the longitudinal axis 114. The distal edge 111 also includes at least one sloping edge portion 130, at least a portion of which (e.g., along most or substantially all of its length, as shown) is generally parallel to the longitudinal axis 114 in its contour or boundary. At a curved merging portion located below the longitudinal axis 114, optionally adjacent to the relative height level of the bottom portion 113, the leading edge portion 120 merges with the sloping edge portion 130. In some embodiments, the catheter tip 102 tapers and decreases toward the distal edge 111 in terms of outer diameter and / or thickness to facilitate catheter penetration into the skin and to a blood vessel.

[0069] The catheter 100 is configured to engage the inner surface of the blood vessel (e.g., as shown in FIG. 2) with the inclined edge portion 130 when pushed over the insertion needle 107, and is configured to slide distally on the inner surface of the blood vessel using the inclined edge portion 130 when the catheter tip 102 is pressed against the vessel wall (in the case of withdrawal of the insertion needle relative to it). Optionally, the catheter 100 is configured to first engage the inner surface of the blood vessel with the inclined edge portion 130 proximal to the insertion needle 107.

[0070] The inclined edge portion 130 includes two sliding surfaces 131 and 132 located on different sides of the longitudinal axis 114. The sliding surfaces 131 and 132 are generally flat along at least a majority of their surface area and both extend along a common plane parallel to the longitudinal axis 114 and parallel to a planar view (e.g., as shown in the figure). Figure 5B The top view or bottom view shown in the figure) and the elevation view perpendicular to the conduit 100 (e.g., as shown in the figure) Figure 5A(Side view shown in the figure). In common practice of peripheral IV access, after penetrating into the vessel, the catheter is often further advanced distally at a shallow angle almost parallel to the inner surface of the vessel. Therefore, the potential advantages of this design feature of the inclined edge portion 130 are twofold: (a) unlike catheters with inclined and / or tapered ends, the inclined edge portion 130 inherently facilitates advancement of the catheter toward the inner surface of the vessel at a greater angle, and the inclined edge portion 130 is generally parallel to the longitudinal axis 114 of the catheter, thus inherently facilitating axial sliding movement above the inner surface of the vessel, and / or (b) unlike known catheters that are typically constructed with rounded edges and / or a small footprint, the inclined edge portion 130 has a significantly larger footprint with respect to the sliding surfaces 131 and 132, and is also flat and smooth, thus providing reduced traction and increased sliding potential on the inner surface of the vessel.

[0071] Each of the sliding surfaces 131 and 132 is distinctly merged with the anterior edge portion 120: the first sliding surface 131 merges at the first merging portion 133, and the second sliding surface 132 merges at the second merging portion 134. The merging portions 133 and 134 are located on different sides of the longitudinal axis 114 and laterally away from it, thus reducing the likelihood of dissecting the vessel wall tissue after accidental puncture of the vessel wall on its inner surface using the needle tip 108. This differs from other catheters that can engage with a single edge portion formed near the needle tip 108 and located on the longitudinal axis 114, which could further enlarge the puncture and ultimately dissect the tissue. Each of the merging portions 133 and 134 is curved and / or angled to allow the catheter 100 to smoothly transition from a larger angle to a shallower angle with respect to the vessel axis when the merging portions 134 and / or 135 directly engage with the inner surface of the vessel. The inclined edge portion 130 also includes a single inclined edge portion 121 at the junction of both sliding surfaces 131 and 132 with the bottom portion 113. The inclined edge portion 121 extends obliquely from the bottom portion 113 toward the front edge portion 120 about the longitudinal axis 114.

[0072] Figures 6A-6C A view of an exemplary vascular access kit 200 is shown, which includes at least a vascular access catheter 201 and an access needle 202. Figure 6A The separated catheter 201 and inlet needle 202 are shown, and Figure 6B The insertion needle 202 is shown, which extends through the catheter 201 and is fixedly connected to the catheter 201 at a predetermined relative longitudinal position. Figure 6C Show Figure 6BA magnified (zoomed-in) view of the distal portion of the kit 200, showing the beveled end 203 of the needle 202 and the catheter end 201 of the catheter 204. Figures 7A-7C The view showing catheter 201 includes a partial isometric view of the distal length of catheter 201, showing a portion of the catheter body having catheter tip 204. Figure 7A ), showing an enlarged view of the anterior portion of the catheter tip 204 ( Figure 7B ), and a side cross-sectional view of the distal length of catheter 201 including catheter tip 204 ( Figure 7C ).

[0073] The catheter 201 includes an elongated tubular catheter body 205 that encloses an inner lumen 206. The inner lumen 206 is cylindrical (e.g., largely) along a portion of the catheter body 205 proximal to the catheter tip 204 and tapers along a portion of the catheter tip 204. The catheter tip 204 (which is the anterior (distal) portion of the catheter body 205) terminates at a distal end 207 and includes a distal edge 208 at the distal end 207 that surrounds an opening 209 opening into the inner lumen 206. The insertion needle 202 includes a hollow needle body 210 and a beveled end 203 ending at a distally pointed needle edge 211. The catheter 201 is configured to receive the insertion needle 202 through the inner lumen 206 and the opening 209 in at least two configurations, including a 'tissue-penetrating configuration' (e.g., Figure 6B , Figure 8A and Figure 9A (as shown in the diagram), wherein the beveled end 203 extends fully from the lumen 206 distal to the distal end 207 of the catheter, and a 'safety feature' (e.g., Figure 8B and Figure 9B (As shown in the diagram), the beveled end 203 is completely residing within the lumen 206 proximal to the distal end 207 of the catheter. The lumen 206 decreases in diameter along the catheter end 204 to a sealing diameter smaller than the diameter of the entry needle proximal to the beveled end 203, so as to form a seal around the entry needle 202 to prevent blood from entering the lumen 206 via the opening 209 (in the tissue penetration configuration) and to facilitate blood entry into the lumen 206 via the opening 209 (in the safety configuration). The catheter 201 and the entry needle 202 include mating portions 212 of a coupling device, optionally in the form of a Luer connector as shown, configured to secure the entry needle 202 within the catheter 201 in the tissue penetration configuration.

[0074] The distal edge 208 includes a front edge portion 213 that spans the top portion of the opening 209; and an inclined edge portion 214 that spans the bottom portion of the opening 209 and is inclined proximally away from the front edge portion 213 relative to the longitudinal axis X of the catheter body 201 (towards the bottom end of the catheter tip 204). The top portion of the opening 209 relates to the cross-sectional area of ​​the opening 209 above the longitudinal axis X, and the bottom portion of the opening 209 relates to the cross-sectional area of ​​the opening 209 below the longitudinal axis X (e.g., ...). Figure 7C (As shown in the diagram). The anterior edge portion 213 substantially coincides with the transverse plane TP of the catheter body 205, which spans perpendicularly to the longitudinal axis X. Optionally, the anterior edge portion 213 spans at least half of the cross-section of the catheter body 205 at the distal end 207. Optionally, at least for most of its portion, the anterior edge portion 213 is substantially parallel to the transverse plane TP. The inclined edge portion 214 is inclined about the longitudinal axis X at an average angle greater than 20° (optionally, particularly, greater than 40°, optionally, particularly, greater than 60°), and / or about the anterior edge portion 213 or the transverse plane TP at an average angle less than 45° (optionally, particularly, less than 30°, optionally, particularly, less than 20°).

[0075] In some embodiments, the front edge portion 213 is at least partially flat, and the sloping edge portion 214 is at least partially curved. Optionally, the radius of curvature of the sloping edge portion 214 is smallest adjacent to the front edge portion 213 and / or largest adjacent to the vertex 215 of the sloping edge portion 214, and the sloping edge portion 214 may optionally gradually increase between the front edge portion 213 and the vertex 215 (optionally, particularly, from the front edge portion 213 to the vertex 215). In some embodiments, the sloping edge portion 214 near its vertex 215 forms a tangential angle of less than approximately 20° with the longitudinal axis X, and / or near its junction with the front edge portion 213 forms another tangential angle of greater than approximately 45° with the longitudinal axis X.

[0076] In some embodiments, catheter 201 is configured to engage the inner surface of the blood vessel with the beveled edge portion 214 when pushed over an insertion needle 202, and is configured to slide distally on the inner surface of the blood vessel using the beveled edge portion 214 when the catheter tip 204 is pressed against the vessel wall (when the insertion needle 202 is withdrawn from the catheter tip 204). When the catheter engages the vessel wall and is pushed against it while tilted relative to the long axis of the vessel, prior art catheters (which include a flat tip with a non-significantly tilted and / or curved portion) can easily damage the vessel wall using their bottom edge, which serves as a sharp edge. Using the curved beveled edge portion 214 overcomes this disadvantage by first reducing the likelihood of damage or penetration of the vessel wall (by reducing or eliminating sharpness, and / or by having a larger footprint area for engaging the vessel wall). Furthermore, because the curved, sloping edge portion 214 has tangents at some or all of its contact points with the vessel wall that are parallel to or nearly parallel to the longitudinal direction of the vessel, it can distribute a larger tangential force component in the longitudinal direction of the vessel lumen, and a smaller normal force component from the force applied by pushing the catheter, directed perpendicularly toward the vessel wall, compared to prior art catheters. It should be noted that the distal edge 208 is not completely sloping and / or curved, so that it includes a significantly sized leading edge portion 213 to maintain sufficient structural integrity of the catheter tip 204 during the penetration of the entry needle 202 through the skin tissue and / or into the vessel in a tissue-penetrating configuration.

[0077] The sloping edge portion 214 includes a sliding surface 217, or is merged with the sliding surface 217. The sliding surface 217 may optionally be at least partially curved and / or flat, and at least partially parallel to the sloping edge portion 214 and / or the longitudinal axis X, or sloping at a shallow angle (e.g., less than 45°, optionally particularly, less than 20°) about the sloping edge portion 214 and / or the longitudinal axis X. The sliding surface 217 forms a shaping region bounded by a distal parabola 218 and a proximal parabola 219, and between the distal parabola 218 and the proximal parabola 219, such that the distal parabola 218 has a focal length less than that of the proximal parabola 219. In some embodiments, when the kit 200 is assembled with a tissue-penetrating construction, compared to the distance to the vertex 216 of the front edge portion 213 (in... Figure 6CAs shown in the figure, the needle edge 211 has a distance equal to or greater than the apex 215 of the inclined edge portion 214 (which is the apex of the distal parabola 218). In some embodiments, the catheter tip 204 varies in thickness along the sliding surface 217, and the sliding surface 217 has an average radius of curvature that is significantly larger than the radius of the outer surface portion of the catheter tip opposite the sliding surface 217 in a common transverse section. In some embodiments, the sliding surface 217 has an elastic resistance to inward radial deformation that is less than the elastic resistance to inward radial deformation of the opposite portion (along the top end) of the catheter tip 204. In some embodiments, the kit 200 is configured such that when collapsing radially inward, the catheter tip 204 has a footprint on the surface of the vessel wall along its bottom portion or end, which is larger in size than the maximum size of damage that can be formed in the vessel wall by the insertion needle 202.

[0078] In addition to preventing damage to the vessel wall by engaging the inner surface of the vessel with the curved, sloping edge portion 214, the catheter tip 204 may also be optionally configured to reduce the likelihood of increased damage (such as accidental vessel wall penetration caused by the sharp needle edge 211) and / or severity (such as by enlarging the puncture size and / or pushing the catheter 201 out of the vessel lumen when the kit 200 is secured with a tissue penetration configuration). The sloping edge portion 214 includes two curved surfaces 220 located on opposite sides of the opening 209 relative to the longitudinal axis X, each of the sliding surfaces 220 being clearly merged with the leading edge portion 213 at a different merging portion 221. Thus, when the catheter tip 204 engages a pre-formed lesion, the initial contact and sliding across the lesion will occur directly with respect to the sliding surface 220, which is farther than the width of the lesion (which is equal to or less than the diameter of the insertion needle 202). Each merged portion 221 may optionally be rounded, curved, and / or tilted, and may optionally be positioned adjacent to or below the longitudinal axis X.

[0079] Figures 8A-8E The first set of exemplary scenarios illustrating the steps in a method for accessing a blood vessel (BV) using kit 200 (inserting catheter 201 into the blood vessel BV) is illustrated schematically. Figure 8AAs shown, the catheter 201 and entry needle 202 of the kit 200 are first assembled and secured together in a tissue-penetrating configuration, and then pushed through the skin layer of a living subject until the blood vessel BV is penetrated using the beveled end 203 to allow blood to be drawn from the blood vessel BV into the entry needle 202. The size of the kit 200 is determined according to the size of the blood vessel so that by properly positioning the beveled end 203 in the lumen of the blood vessel BV in the tissue-penetrating configuration, the catheter end 204 is also (e.g., mostly or completely) inserted into the blood vessel BV. Catheter insertion may include verification that the opening 209 or the bottom portion of the catheter end 204 faces the blood vessel BV guide, and / or the opening 209 or the top portion of the catheter end 204 is away from the blood vessel BV guide, to indicate correct positioning and orientation. When properly penetrated through the skin and into the blood vessel BV (e.g., as shown), the top portion of the anterior edge portion 213 functions as the anterior edge of the catheter, while the sloping edge portion 214 is sufficiently displaced proximally to reduce or avoid a significant contribution to the physical interaction with the surrounding tissues during catheter insertion relative to the contribution of the anterior edge portion 213.

[0080] Once the beveled tip 203 is in the lumen of the blood vessel BV, the practitioner can verify that blood has been drawn from the blood vessel BV into the entry needle 202, which indicates the proper positioning of the beveled needle 203. After this, the catheter 201 and entry needle 202 can be switched to a safe configuration (e.g., by moving the beveled tip 203 relative to the catheter tip 204). Figure 8B (As shown in the diagram), the beveled end 203 is completely residing within the lumen 206 proximal to the distal end 207 of the catheter. This transition step may follow or include changes in the tilt of the catheter 201 and the entry needle 202 relative to the vessel BV, and / or repositioning of the catheter 201 and / or the entry needle 202 within the vessel BV.

[0081] When in a secure configuration, the practicing physician can verify that blood has been drawn from the vessel BV into the lumen 206 of the catheter 201 before proceeding to complete its deployment. This can then be further withdrawn into the needle 202, and / or the catheter 201 can be pushed forward (distally) over the needle 202, which may include engaging the inner (e.g., deeper) surface of the vessel BV with the sloping edge portion 214, as... Figure 8C As shown in the diagram. The insertion needle 202 can be completely removed from the lumen 206 and can optionally be replaced by a fluid source (such as a syringe that can be connected to the catheter 201 using a coupling device 212, which can be used to flush the catheter and / or to administer medication to the vascular BV via the catheter 201). Removal of the insertion needle 202 and / or syringe coupling can be performed when the vascular BV is compressed distal to the catheter tip 204, as shown in the diagram. Figure 8D As shown in the diagram. Catheter 201 can then be advanced distally within the blood vessel. Figure 8E ), for final positioning and deployment.

[0082] Figures 9A-9F A second set of exemplary scenarios illustrating the steps in a method for accessing a blood vessel (BV) using kit 200 is illustrated. In this set of scenarios, the practitioner may intentionally (e.g., deliberately) or unintentionally push an entry needle 202 with catheter 201 across the entire width of the blood vessel BV in a tissue-penetrating configuration, such that the beveled end 203 penetrates both the top (shallow) portion and the opposite bottom (deep) portion of the blood vessel BV, for example, as... Figure 9A As shown in the illustration. In this example, when inserting the catheter tip 204 into the blood vessel BV in a tissue-penetrating configuration, it includes or causes damage LS to be formed by using the beveled tip 203 to penetrate the inner surface of the blood vessel BV wall (e.g., in...). Figure 9C (as shown in the diagram). Then, before proceeding to the final deployment phase of catheter 201 in the vessel BV, catheter 201 may be withdrawn back into the lumen of the vessel BV until correct positioning is achieved and / or confirmed. Before withdrawing catheter 201, the insertion needle 202 may be partially withdrawn from catheter 201 (e.g., to a safety configuration) or completely withdrawn from catheter 201 (e.g., removed).

[0083] "Penetrating" penetration of blood vessel BV (such as...) Figure 9A Afterwards (as shown in the diagram), the practicing physician may first verify that blood has been drawn from the vessel BV into the entry needle 202, although in this scenario, verification may result in invalid blood being drawn into the entry needle (i.e., indicating or proving that no blood was actually drawn from the vessel BV into the entry needle 202). Regarding such results, catheter 201 and entry needle 202 may first be switched to a safety configuration (…). Figure 9B Alternatively, the insertion needle 202 is removed from the catheter 201, and the catheter 201 can then be gradually withdrawn, optionally wherein the insertion needle 202 remains in a safety configuration. Figure 9C This continues until blood is verified to be drawn from the vessel BV into the lumen 206 (indicating or proving that the catheter tip 204 is inserted into the vessel BV). The catheter 201 can then be advanced and engage the inner surface of the vessel BV with the inclined edge portion 214. Figure 9D (Optionally, the sliding surface 220 of the inclined edge portion 214 can be used to slide across the injured LS from the opposite side of the lesion LS over the distal portion of the inner surface of the vessel BV, without penetrating through the lesion LS again or damaging the surrounding tissue.) If this is not completed in the early stages, the insertion needle 202 can be completely removed from the lumen 206 of the catheter 201. Figure 9E ), and the catheter 201 can be advanced distally to the selected deployment location ( Figure 9FAdvancement of catheter 201 may optionally include sliding the inclined edge portion 214 and / or catheter tip 204 along its bottom end, which includes a sliding surface 217, over and across the lesion LS.

[0084] In some embodiments, the advantages of using catheter 201 and / or kit 200 are particularly relevant for accessing diseased or very small veins. In small veins, the diameter at the point of entry may be approximately the size of the catheter body or even smaller, thus at any given time along the entry and deployment process, there may be at least some engagement with the vessel wall via the distal edge or portion of the distal end of the prior art catheter. By applying catheter 201 with a sloping edge portion 214, this results in a smaller relative height during sloping penetration into the vessel compared to using a standard catheter. In some such embodiments, the preparatory steps in the method for deploying catheter 201 using kit 200 may include verifying that the vessel is diseased and / or a vein that is equal to or smaller than the catheter body in diameter, or equal to or smaller than approximately 1 mm.

[0085] Each of the following terms (written in the singular grammatical form: 'a', 'an', and 'the', as used herein) means 'at least one' or 'one or more'. The use of the phrase 'one or more' herein does not alter the intended meaning of 'a', 'an', and 'the'. Thus, the terms 'a', 'an', and 'the' as used herein may also refer to and include multiple described entities or objects, unless otherwise expressly defined or stated herein, or unless the context clearly indicates otherwise. For example, the phrases 'unit', 'device', 'component', 'mechanism', 'building block', 'element', and 'step or procedure' as used herein may also refer to and include multiple units, multiple devices, multiple components, multiple mechanisms, multiple building blocks, multiple elements, and multiple steps or procedures, respectively.

[0086] As used herein, each of the following terms—'including,' 'containing,' 'having,' 'possessing,' 'comprising,' and 'including', and their linguistic / grammatical variations, derivatives, and / or conjugates—means 'including but not limited to,' and will be considered to indicate (multiple) components, (multiple) features, (multiple) properties, (multiple) parameters, (multiple) integers, or (multiple) steps of a statement, without excluding the addition of one or more additional (multiple) components, (multiple) features, (multiple) properties, (multiple) parameters, (multiple) integers, (multiple) steps, or groups thereof. Each of these terms is considered semantically equivalent to the phrase "substantially composed of...".

[0087] As used herein, the term 'method' refers to steps, procedures, ways, means, or / and techniques for accomplishing a given task, including but not limited to those steps, procedures, ways, means, or / and techniques that are known to those skilled in the art of the disclosed invention(s) or readily developed from known steps, procedures, ways, means, or / and techniques.

[0088] Throughout this disclosure, numerical values ​​of parameters, features, characteristics, objects, or sizes may be described or narrated in a number range format. Such number range formats used herein illustrate implementations of some exemplary embodiments of the invention and do not inflexibly limit the scope of exemplary embodiments of the invention. Therefore, a number range narrated or described also refers to and includes all possible subranges and individual numerical values ​​within the number range narrated or described (wherein the numerical value may be represented as a non-negative integer, integer, or fraction). For example, the stated or described range of numbers 'from 1 to 6' also refers to and includes all possible subranges (such as 'from 1 to 3', 'from 1 to 4', 'from 1 to 5', 'from 2 to 4', 'from 2 to 6', 'from 3 to 6', etc.), as well as individual numerical values ​​(such as '1', '1.3', '2', '2.8', '3', '3.5', '4', '4.6', '5', '5.2', and '6' within the stated or described range of numbers 'from 1 to 6'). This applies regardless of the width, range, or size of the stated or described range of numbers.

[0089] Furthermore, to describe a range of numbers, the phrase 'between approximately the first value and approximately the second value' is considered equivalent to 'between approximately the first value and approximately the second value' and has the same meaning; therefore, the two equivalent phrases can be used interchangeably. For example, to describe a range of room temperature, the phrase 'room temperature refers to the temperature between approximately 20°C and approximately 25°C' is considered equivalent to the phrase 'room temperature refers to the temperature between approximately 20°C and approximately 25°C' and has the same meaning.

[0090] As used in this article, the term "approximately" refers to a numerical value. 10%.

[0091] It will be fully understood that certain aspects, features, and characteristics of the invention (which are illustratively described and presented in the context or format of several individual embodiments for clarity) may also be illustratively described and presented in the context or format of a single embodiment in any suitable combination or sub-combination. Conversely, various aspects, features, and characteristics of the invention (which are illustratively described and presented in the context or format of a single embodiment in combination or sub-combination) may also be illustratively described and presented in the context or format of several individual embodiments.

[0092] Although the invention has been illustratively described and presented through specific exemplary embodiments and examples, it will be apparent to those skilled in the art that many alternatives, modifications, and / or variations thereof will be readily apparent. Therefore, it is intended that all such alternatives, modifications, and / or variations fall within and are encompassed by the broad scope of the appended claims.

[0093] To the same extent that each individual publication, patent, and / or patent application is expressly and individually indicated as incorporated herein by reference, all publications, patents, and / or patent applications cited or mentioned in this disclosure are incorporated herein by reference in their entirety. Furthermore, any reference or designation in this specification should not be construed or interpreted as an admission that such reference represents or corresponds to prior art of the invention. The use of section headings should not be construed as necessarily limiting.

Claims

1. A vascular access catheter, comprising: A slender tubular catheter body encloses an inner lumen, the catheter body including a catheter tip, the catheter tip ending at a distal end and including a distal edge at the distal end, the distal edge surrounding an opening to the inner lumen; The vascular access catheter is configured to accommodate an access needle that passes through the lumen and the opening; The distal edge includes a front edge portion and a sloping edge portion, the front edge portion extending across the top portion of the opening, and the sloping edge portion extending across the bottom portion of the opening and sloping proximally away from the front edge portion relative to the longitudinal axis of the catheter body; The inclined edge portion of the opening is at least partially bent in the longitudinal section; The distal edge (111, 208) includes a merged portion (122, 133, 134, 221) adjacent to the front edge portion (120, 213), which connects the front edge portion (120, 213) to the inclined edge portion; The merging portion (122, 133, 134, 221) and the inclined edge portion extend across the bottom portion of the opening; The inclined edge portion is inclined proximally away from the anterior edge portion (213) relative to the longitudinal axis (X) of the catheter body (101, 205); And wherein the inclined edge portion is less curved than the merging portion (122, 133, 134, 221) to form a sliding surface on the bottom portion of the conduit near the opening (119, 209).

2. The vascular access catheter according to claim 1, wherein, The inner lumen is cylindrical along a portion of the catheter body proximal to the catheter tip and tapers along the portion of the catheter tip to seal around the entry needle as it extends through the inner lumen.

3. The vascular access catheter according to claim 1, wherein, The radius of curvature in the longitudinal section of the inclined edge portion is at least one of the following: (a) the smallest adjacent to the front edge portion, or (b) the largest adjacent to the vertex of the inclined edge portion.

4. The vascular access catheter according to claim 1, wherein, The radius of curvature of the inclined edge portion gradually increases between the front edge portion and the vertex of the inclined edge portion.

5. The vascular access catheter according to claim 1, wherein, The sliding surface forms a shaping region, which is bounded by a far parabola and a near parabola and lies between the far parabola and the near parabola, wherein the far parabola has a focal length smaller than that of the near parabola.

6. The vascular access catheter according to claim 1, wherein, The sliding surface is at least partially curved.

7. The vascular access catheter according to claim 1, wherein, The thickness of the catheter tip varies along the sliding surface.

8. The vascular access catheter according to claim 1, wherein, The sliding surface has an average radius of curvature that is significantly larger than the radius of the outer surface portion of the conduit end opposite the sliding surface in the common transverse section.

9. The vascular access catheter according to claim 1, wherein, The inclined edge portion includes two curved surfaces located on opposite sides of the opening relative to the longitudinal axis.

10. The vascular access catheter according to claim 1, wherein, The catheter is configured to engage the inner surface of the blood vessel with the inclined edge portion when pushed over the insertion needle, and is configured to slide distally on the inner surface of the blood vessel using the inclined edge portion when the insertion needle is withdrawn from the catheter tip and the catheter tip is pressed against the blood vessel wall.

11. The vascular access catheter according to claim 1, wherein, The front edge portion merges with the inclined edge portion at the merging portion, wherein the merging portion is curved or inclined.

12. The vascular access catheter according to claim 1, wherein, The merged portion is positioned below and adjacent to the longitudinal axis.

13. The vascular access catheter according to claim 1, wherein, The catheter tip includes a groove or slit that extends along the bottom portion of the catheter tip, extends proximally from the sloping edge portion, and opens to the sloping edge portion.

14. The vascular access catheter according to claim 1, wherein, The inclined edge portion near its vertex forms a first tangential angle with the longitudinal axis, the first tangential angle being less than 20°.

15. The vascular access catheter according to claim 1, wherein, The inclined edge portion adjacent to the front edge portion forms a second tangential angle with the longitudinal axis, the second tangential angle being greater than 45°.

16. The vascular access catheter according to claim 1, wherein, The bottom portion of the catheter tip has an elastic resistance to inward radial deformation that is less than the elastic resistance to inward radial deformation of the top portion of the catheter tip.

17. The vascular access catheter according to claim 1, wherein, When not supported internally by the insertion needle, the catheter tip is configured to collapse radially inward when the bottom portion of the catheter tip is pressed against the vessel wall at an angle, and when the catheter body transmits a force to the vessel wall that is insufficient to cause mechanical damage to it.

18. The vascular access catheter of claim 1, wherein the catheter is configured such that when it collapses radially inward, the distal end of the catheter has a berthing area on the surface of the vessel wall along its bottom portion that is larger in size than the cross-section of the maximum size of the access needle.

19. A vascular access kit comprising: Vascular inlet catheter according to any one of the preceding claims; as well as The insertion needle comprises a hollow needle body and a beveled end that terminates at a distal, sharp needle edge.

20. The kit of claim 19, wherein, The vascular access catheter is configured to accommodate the access needle passing through the lumen and the opening in at least two configurations, including a tissue penetration configuration and a safety configuration, wherein in the tissue penetration configuration the beveled end extends fully from the lumen to the distal end of the catheter, and in the safety configuration the beveled end remains fully within the lumen to the proximal end of the catheter.

21. The kit of claim 20, wherein, The lumen decreases in diameter along the distal end of the catheter to a sealing diameter smaller than the diameter of the entry needle proximal to the beveled distal end, so as to form a seal around the entry needle in the tissue penetration configuration to prevent blood from entering the lumen through the opening, and to facilitate blood entry into the lumen through the opening in the safety configuration.

22. The kit of claim 20, the kit comprising a coupling device configured to secure the entry needle in the catheter within the tissue penetration configuration.

23. The kit according to claim 20, wherein, When the tissue penetration structure is in place, the needle edge has a distance equal to or greater than the distance to the vertex of the inclined edge portion compared to the distance to the vertex of the front edge portion.

24. The kit of claim 19, wherein the kit is configured such that when collapsing radially inward, the catheter tip has a footprint on the surface of the vessel wall along its bottom portion that is larger in size than the maximum size of damage that can be formed in the vessel wall by the insertion needle.

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