Assisted Catheter Advancement

Abstract

The catheter assembly may include an introducer needle (120) coupled to a needle hub (130), an intermediate member (200) having a contact surface (115), a resilient member (300), and a ramp member (220). The resilient member (300) may be coupled to one of the needle hub (130) and the intermediate member (200). The ramp member (220) may be coupled to the other of the needle hub (130) and the intermediate member (200). The resilient member (300) may engage the ramp surfaces (221, 222, 223, 224, 241, 242) of the ramp member (220) and apply a force to the intermediate member (200) in a distal direction. The contact surface of the intermediate member (200) may engage the proximal surface of the catheter adapter body (160) and bias the catheter adapter body (160) in a distal direction such that the catheter (170) protruding from the catheter adapter body (160) translates distally relative to the introducer needle (120).

Description

[Background technology]

[0001] background Catheters are commonly used for a variety of infusion therapies. For example, catheters may be used to infuse fluids, such as saline, medications, total parenteral nutrition, etc. into a patient. Catheters may also be used to withdraw blood from a patient.

[0002] A common type of catheter is the over-the-needle peripheral intravenous catheter ("PIVC"). Other common types of catheters include, but are not limited to, peripherally inserted central catheters ("PICC"), central venous catheters ("CVC"), etc.

[0003] As the name suggests, an over-the-needle PIVC may be mounted on an introducer needle that has a sharp distal tip. The PIVC and introducer needle may be assembled such that the distal tip of the introducer needle extends beyond the distal tip of the PIVC, with the bevel of the needle pointing away from the patient's skin. The PIVC and introducer needle are typically inserted at a shallow angle through the skin and into the patient's blood vessel, such as the patient's artery, vein, or any other vascular system. Once the PIVC is properly positioned within the vessel, the introducer needle may be withdrawn and the catheter adapter (coupled with the PIVC) secured to the patient's skin with a bandage, thereby securing the PIVC within the vessel. Summary of the Invention [Problem to be solved by the invention]

[0004] Some PIVCs can be associated with a variety of additional components, such as valve components, needle safety components, etc., which can provide many additional useful features to the practitioner. However, these additional components can also introduce undesirable characteristics into the PIVC system. For example, these additional components may lead to: (1) an increase in the overall length of the PIVC system, requiring a longer introducer needle; (2) new sources of friction transmitted to the introducer needle by the additional / longer components (e.g., the introducer needle may experience a higher initial tensile force when withdrawing / advancing the introducer needle through the additional / longer components, which can interfere with the practitioner's sense of touch and ability to properly place and maintain the catheter within the patient's vein); and (3) an increase in the length of the introducer needle that is unsupported by other components of the PIVC system as the introducer needle is withdrawn from them. This longer "unsupported portion" of the introducer needle can result in increased bending, which may allow other parts of the PIVC system to "wobble" back and forth thinly, resulting in dislodgement of the catheter from the vein. Thus, improved catheter assemblies, systems, and methods are desirable.

[0005] The subject matter claimed herein is not limited to embodiments that solve any shortcomings, nor does it operate exclusively in the environments described above. Rather, this background is only provided to illustrate one example technology area where some embodiments described herein may be practiced.

[0006] overview The present disclosure relates generally to catheter assemblies, systems, and methods. The various catheter assemblies, systems, and methods of the present disclosure have been developed in response to the current state of the art, and in particular in response to problems and needs in the art that have not yet been fully addressed by currently available catheter assemblies, systems, and methods for catheterizing a patient's blood vessels. [Means for solving the problem]

[0007] In some embodiments, the catheter system may include a needle assembly, a drive spring, and a needle safety shield. The needle assembly may include an introducer needle and a needle hub coupled to the introducer needle. The drive spring may be coupled to the needle hub. The drive spring may include an upper portion having a first spring arm, a second spring arm, and a first cross member coupling the first spring arm to the second spring arm. The drive spring may include a lower portion having a third spring arm, a fourth spring arm, and a second cross member coupling the third spring arm to the fourth spring arm. The drive spring may further include a first resilient portion and a second resilient portion. The first resilient portion may couple the first spring arm to the third spring arm, and the second resilient portion may couple the second spring arm to the fourth spring arm. The first and second resilient portions may apply a biasing force to the first and second cross members to urge the first and second cross members toward one another. The needle safety shield may include a contact surface disposed at a distal end of the needle safety shield, and the needle safety shield may be configured to slidably receive the introducer needle therein. The needle safety shield may also include a ramp member disposed at a proximal end of the needle safety shield. The ramp member may include a first ramp surface configured to receive a first guide surface of the first cross member, a second ramp surface configured to receive a second guide surface of the first cross member, a third ramp surface configured to receive a third guide surface of the second cross member, and a fourth ramp surface configured to receive a fourth guide surface of the second cross member. The drive spring may be configured to engage the ramp member and apply a force to the needle safety shield to urge the needle safety shield distally relative to the needle hub. The contact surface of the needle safety shield may engage a proximal surface of the catheter adapter body to urge the catheter adapter body distally relative to the needle hub, and a catheter protruding from the distal end of the catheter adapter body may translate distally relative to the introducer needle.

[0008] In some embodiments of the catheter system, the first and second cross members may be configured to grip the introducer needle between the first and second cross members when the first and second cross members are biased together.

[0009] In some embodiments of the catheter system, the first angled surface may include a first concave surface portion, the second angled surface may include a second concave surface portion, the third angled surface may include a third concave surface portion, and the fourth angled surface may include a fourth concave surface portion.

[0010] In some embodiments of the catheter system, the first concave surface portion may include a first radius, the second concave surface portion may include a second radius, the third concave surface portion may include a third radius, and the fourth angled surface may include a fourth radius.

[0011] In some embodiments of the catheter system, the first radius, the second radius, the third radius, and the fourth radius may be substantially equal to one another.

[0012] In some embodiments of the catheter system, the ramp member may include at least one plateau portion.

[0013] In some embodiments of the catheter system, the ramp member may include at least one stop ridge adjacent to the at least one plateau portion.

[0014] In some embodiments, the catheter assembly may include an introducer needle coupled to a needle hub, an intermediate member, a resilient member, and a ramp member. The intermediate member may include a contact surface disposed at a distal end of the intermediate member. The intermediate member may be configured to slidably receive the introducer needle therein. The resilient member may be coupled to one of the needle hub and the intermediate member. The ramp member may be coupled to the other one of the needle hub and the intermediate member. The resilient member may be configured to engage at least one ramp surface of the ramp member and apply a force to the intermediate member to urge the intermediate member in a distal direction relative to the needle hub. The contact surface of the intermediate member may engage a proximal surface of the catheter adapter body to urge the catheter adapter body in a distal direction relative to the needle hub, and a catheter protruding from a distal end of the catheter adapter body may be translated in a distal direction relative to the introducer needle.

[0015] In some embodiments of the catheter assembly, the resilient member may include a drive spring. The drive spring may include an upper portion having a first spring arm, a second spring arm, and a first cross member connecting the first spring arm to the second spring arm. The drive spring may include a lower portion having a third spring arm, a fourth spring arm, and a second cross member connecting the third spring arm to the fourth spring arm. The drive spring may also include a first resilient portion and a second resilient portion. The first resilient portion may connect the first spring arm to the third spring arm, and the second resilient portion may connect the second spring arm to the fourth spring arm, and the first and second resilient portions may apply a biasing force to the first and second cross members to urge the first and second cross members toward each other. In some embodiments, the catheter system may include two or more resilient portions and / or four or more angled surfaces.

[0016] In some embodiments of the catheter assembly, the first and second cross members may be configured to grip the introducer needle between the first and second cross members when the first and second cross members are biased together.

[0017] In some embodiments of the catheter assembly, the at least one angled surface of the angled member may include a first angled surface configured to receive a first guide surface of the first cross member, a second angled surface configured to receive a second guide surface of the first cross member, a third angled surface configured to receive a third guide surface of the second cross member, and a fourth angled surface configured to receive a fourth guide surface of the second cross member.

[0018] In some embodiments of the catheter assembly, the at least one angled surface may include a concave surface portion having a first radius.

[0019] In some embodiments of the catheter assembly, the at least one sloping surface may include a plateau portion.

[0020] In some embodiments of the catheter assembly, the at least one sloping surface may include a stop ridge intermediate the concave surface portion and the plateau portion.

[0021] In some embodiments, a method of inserting a catheter into a patient's blood vessel may be facilitated by the use of a catheter assembly that may include an introducer needle coupled to a needle hub, an intermediate member having a contact surface disposed at a distal end of the intermediate member, a resilient member coupled to one of the needle hub and the intermediate member, and a ramp member coupled to the other of the needle hub and the intermediate member. The method may include inserting a distal end of the introducer needle into a patient's blood vessel and proximally advancing the intermediate member relative to the introducer needle, thereby (1) engaging the resilient member with the ramp surface of the ramp member to apply a force to the intermediate member and urging the intermediate member distally relative to the needle hub, (2) engaging the contact surface of the intermediate member with a proximal surface of the catheter adapter body to urge the catheter adapter body distally relative to the needle hub; and (3) urging a catheter coupled to the catheter adapter body distally relative to the introducer needle until the distal end of the catheter is inserted into the blood vessel.

[0022] In some embodiments of the method, the method may further include moving the needle hub and introducer needle proximally relative to the catheter and withdrawing the introducer needle from the catheter.

[0023] In some embodiments of the method, the resilient member may include a drive spring. The drive spring may include an upper portion having a first spring arm, a second spring arm, and a first cross member coupling the first spring arm to the second spring arm. The drive spring may include a lower portion having a third spring arm, a fourth spring arm, and a second cross member coupling the third spring arm to the fourth spring arm. The drive spring may further include a first resilient portion and a second resilient portion. The first resilient portion may couple the first spring arm to the third spring arm, and the second resilient portion may couple the second spring arm to the fourth spring arm, and the first and second resilient portions may apply a biasing force to the first and second cross members to urge the first and second cross members toward one another.

[0024] In some embodiments of the method, the first and second cross members may be configured to grip the introducer needle between the first and second cross members when the first and second cross members are biased toward one another. The method may further include gripping the introducer needle between the first and second cross members of the drive spring when the introducer needle is at least partially withdrawn from the catheter.

[0025] In some embodiments of the method, the ramped surfaces may include a first ramped surface configured to receive a first guide surface of the first cross member, a second ramped surface configured to receive a second guide surface of the first cross member, a third ramped surface configured to receive a third guide surface of the second cross member, and a fourth ramped surface configured to receive a fourth guide surface of the second cross member. The method further includes (1) engaging the first guide surface with the first ramped surface and applying a first force urging the intermediate member in a distal direction relative to the needle hub, (2) engaging the second guide surface with the second ramped surface and applying a second force urging the intermediate member in a distal direction relative to the needle hub, (3) engaging the second ramped surface with the second ramped surface and applying a third force urging the intermediate member in a distal direction relative to the needle hub, and (4) engaging the fourth guide surface with the fourth ramped surface and applying a fourth force urging the intermediate member in a distal direction relative to the needle hub.

[0026] In some embodiments of the method, the ramped surface may include a concave surface portion having a first radius, and the method may further include engaging a resilient member with the concave surface portion to apply a force to the intermediate member and urging the intermediate member in a distal direction relative to the needle hub.

[0027] It should be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not intended to limit the embodiments of the present disclosure as claimed. It should be understood that the various embodiments of the present disclosure are not limited to the arrangements and equipment shown in the drawings. It should also be understood that the embodiments of the present disclosure may be combined or other embodiments may be utilized, and structural changes may be made without departing from the spirit or scope of the various embodiments of the present disclosure, unless so claimed. Therefore, the following detailed description is not to be taken in a limiting sense.

[0028] Example embodiments will be described and explained with additional specificity and detail through the use of the accompanying drawings. [Brief description of the drawings]

[0029] [Figure 1A] FIG. 1A is an exploded perspective view of an exemplary catheter system according to some embodiments. [Figure 1B] FIG. 1B is an assembled side cross-sectional view of the exemplary catheter system of FIG. 1A. [Figure 2A] FIG. 2A is a top perspective view of a needle safety shield, according to some embodiments. [Figure 2B] FIG. 2B is a bottom perspective view of the needle safety shield of FIG. 2A. [Figure 2C] FIG. 2C is a side view of the needle safety shield of FIG. 2A. [Figure 3A] FIG. 3A is a top perspective view of a drive spring, according to some embodiments. [Figure 3B] FIG. 3B is a front view of the drive spring of FIG. 3A. [Figure 3C] FIG. 3C is a top perspective view of the drive spring of FIG. 3A showing the distal ends of the drive spring pulled apart. [Figure 4A] 4A-4C are various side views of the drive spring of FIG. 3A as it is loaded onto the ramp member of the needle safety shield of FIG. 2A and a side view of the drive spring before it is loaded onto the ramp member. [Figure 4B] 4B is various side views of the drive spring of FIG. 3A as it rests on the ramp member of the needle safety shield of FIG. 2A, including a side view of the drive spring sliding up the ramp member. [Figure 4C] 4A-4C are various side views of the drive spring of FIG. 3A when loaded onto the ramp member of the needle safety shield of FIG. 2A, including a side view of the drive spring when fully loaded onto the ramp member. [Figure 5A] FIG. 5A is a top perspective view of a drive spring loaded on a ramp member according to some alternative embodiments. [Figure 5B] FIG. 5B is a side cross-sectional view of the drive spring fully loaded on the ramp member of FIG. 5A. [Figure 6] FIG. 6 is a side cross-sectional view of an exemplary catheter system incorporating the drive spring and ramp member of FIG. 5A. [Figure 7] FIG. 7 is a partial cross-sectional side view of an exemplary catheter system, according to some alternative embodiments. [Figure 8] FIG. 8 is a flow chart of a method for inserting a catheter into a patient's blood vessel.

[0030] It is understood that the figures are for purposes of illustrating the concepts of the disclosure and may not be drawn to scale. Further, the figures depict example embodiments and are not intended to represent limitations on the scope of the disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] Exemplary embodiments of the present disclosure are best understood by reference to the drawings, where like parts are designated with like numerals throughout. It will be readily understood that the components of the present disclosure, as generally described and illustrated in the figures herein, could be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of device and system embodiments as depicted in the figures is not intended to limit the scope of the present disclosure as claimed in this application or any other application claiming priority to this application, but are merely representative of exemplary embodiments of the present disclosure.

[0032] 1A and 1B show various views of an exemplary catheter system 100 (or catheter assembly) that may be utilized with the teachings of the present disclosure, according to some embodiments. Specifically, FIG. 1A is an exploded view of the exemplary catheter system 100, and FIG. 1B is a side cross-sectional view of the exemplary catheter system 100 after the exemplary catheter system 100 has been assembled.

[0033] The catheter system 100 may generally include a needle assembly 110, a needle safety shield 140, a catheter adapter body 160, and a catheter 170 coupled to and protruding from a distal end of the catheter adapter body 160. The needle assembly 110 may include an introducer needle 120 coupled to a needle hub 130. The needle safety shield 140 may include a septum 141 configured to slidably receive the introducer needle 120 therein and a contact surface 115 disposed at the distal end of the needle safety shield 140. The catheter adapter body 160 may include a proximal surface 165 configured to engage the contact surface 115 of the needle safety shield 140, as described in more detail below with respect to Figures 2A-8.

[0034] 2A-2C show various views of a needle safety shield 200 (or intermediate member) according to some embodiments. The needle safety shield 200 may be utilized with the exemplary catheter system 100 of FIGS. 1A and 1B, or with any other suitable catheter system known or contemplated in the art. The needle safety shield 200 may generally include a needle safety shield portion 210 disposed at a distal end 202 of the needle safety shield 200 and a beveled member portion (or beveled member 220) disposed at a proximal end 201 of the needle safety shield 200.

[0035] The needle safety shield portion 210 may include a contact surface 215 at the distal end of the needle safety shield portion 210. The needle safety shield portion 210 may be configured to trap the distal end of the introducer needle 120 therein to protect the practitioner from accidental exposure to the sharp distal end of the introducer needle 120. The needle safety shield portion 210 (and / or the angled member 220) may further include one or more internal septa (not shown), which may be configured to facilitate proper valving of fluids in a catheter system utilizing the modified needle safety shield 200 shown in FIGS. 2A-2C.

[0036] In at least some embodiments, the ramp member 220 may be integrally formed with the needle safety shield portion 210. For example, the ramp member 220 may be integrally formed with the needle safety shield portion 210 via an injection molding process. However, it will be appreciated that in other embodiments, the ramp member 220 may not be integrally formed with the needle safety shield portion 210. For example, the ramp member 220 and the needle safety shield portion 210 may be formed separately and then bonded together via a bonding process, or may not be bonded at all. Furthermore, in some catheter system embodiments, the ramp member 220 may be utilized without the needle safety shield portion 210 to form a simple intermediate member. In still further embodiments, the ramp member 220 may be combined with any number of different components to form any number of different intermediate members incorporating the ramp member 220.

[0037] Generally, the ramp member 220 may include a first ramp surface 221, a second ramp surface 222, a third ramp surface 223, a fourth ramp surface 224, a first plateau portion 231, a second plateau portion 232, a first stop ridge 241, a second stop ridge 242, and a ramp protrusion 250 having a ramp needle opening 251 formed therethrough.

[0038] Each angled surface may be angled relative to the introducer needle 120 that may pass through the angled needle opening 251. The magnitude or slope of the angle associated with a given angled surface generally determines the amount of distally directed force that may be generated by a drive spring pushing against the angled surface, as discussed in more detail below.

[0039] In some embodiments, each sloping surface may also include a surface portion that includes a concave. For example, the first sloping surface 221 may include a first concave surface portion, the second sloping surface 222 may include a second concave surface portion, the third sloping surface 223 may include a third concave surface portion, and the fourth sloping surface 224 may include a fourth concave surface portion. Additionally, each concave surface portion may have a radius associated with each concave surface portion. For example, the first concave surface portion may have a first radius, the second concave surface portion may have a second radius, the third concave surface portion may have a third radius, and the fourth sloping surface portion may have a fourth radius. In at least one embodiment, each of the first radius, the second radius, the third radius, and the fourth radius may be substantially equal to one another. However, it will be appreciated that in other embodiments, the first radius, the second radius, the third radius, and / or the fourth radius may be similar and / or different from one another in any combination.

[0040] The magnitude of the radius associated with the concave ramp surface generally determines the maximum and minimum forces that can be generated by the drive spring pushing against the concave ramp surface (this is discussed in more detail below). The radius of the concave ramp surface also determines the transition force characteristics imparted to the introducer needle as the drive spring moves along the concave ramp surface from the top of the concave ramp surface (maximum force) toward the bottom of the concave ramp surface (minimum force). For example, the concave ramp surface may be designed with a radius that substantially normalizes the initial phase of pulling force experienced by the introducer needle (e.g., when the practitioner first begins to withdraw the introducer needle from the catheter system) by applying an appropriate maximum force to the introducer needle early in the withdrawal. However, as the practitioner continues to withdraw the introducer needle from the catheter system, the pulling force experienced by the introducer needle will typically decrease. Thus, as the drive spring moves along the concave sloped surface and transitions between maximum force (e.g., when the drive spring is at the top of the concave sloped surface) and minimum force (e.g., when the drive spring is at the bottom of the concave sloped surface), the radius of the concave sloped surface also helps the introducer needle maintain a normalized tension force profile by continually reducing the force applied to the introducer needle as it is withdrawn from the catheter system.

[0041] In some embodiments, the first stop ridge 241 may be disposed adjacent and / or intermediate between the first and second angled surfaces 221, 222 and the first plateau portion 231, and the second stop ridge 242 may be disposed adjacent and / or intermediate between the third and fourth angled surfaces 223, 224 and the second plateau portion 232. The shape of the first and second plateau portions 231, 232 and the first and second stop ridges 241, 242 may help bias the drive spring to keep it in place on the angled member 220 (e.g., fully loaded on the angled member 220) until the practitioner is ready to withdraw the introducer needle from the catheter system.

[0042] The angled protrusions 250 may also help reduce bending and "wobble" in the introducer needle passing through the angled needle opening 251. The angled protrusions 250 can accomplish this by reducing the length of the introducer needle that is not supported by other components of the catheter system when the introducer needle is at least partially withdrawn from the catheter system.

[0043] Figures 3A-3C show various views of a resilient member or drive spring 300, according to some embodiments. Specifically, Figure 3A is a top perspective view of drive spring 300, Figure 3B is a front view of drive spring 300, and Figure 3C is a top perspective view of drive spring 300 shown in a separated view. Generally, drive spring 300 includes an upper portion 301, a lower portion 302, a first resilient portion 341, and a second resilient portion 342.

[0044] The upper portion 301 may include a first spring arm 311, a second spring arm 312, and a first cross member 321 connecting the first spring arm 311 to the second spring arm 312. Similarly, the lower portion 302 may include a third spring arm 313, a fourth spring arm 314, and a second cross member 322 connecting the third spring arm 313 to the fourth spring arm 314. The second resilient portion 342 may connect the first spring arm 311 to the third spring arm 313, and the first resilient portion 341 may connect the second spring arm 312 to the fourth spring arm 314. The first and second resilient portions 341, 342 may each apply one or more biasing forces to the first and second cross members 321, 322 to urge the first and second cross members 321, 322 toward one another. In at least some embodiments, the first and second cross members 321, 322 may be configured to grip an introducer needle between the first and second cross members 321, 322 when the first and second cross members 321, 322 are biased toward one another. For example, as shown in FIG. 3B, a spring needle opening 325 may be formed between the first and second cross members 321, 322. The spring needle opening 325 may be sized to receive and / or grip an introducer needle between the first and second cross members 321, 322 when the first and second cross members 321, 322 are biased toward one another by the first and second resilient portions 341, 342.

[0045] In at least some embodiments, the first cross member 321 may include a first guide surface 331 and a second guide surface 332. The second cross member 322 may include a third guide surface 333 and a fourth guide surface 334. In these embodiments, the first angled surface 221 may be configured to receive the first guide surface 331 of the first cross member 321, the second angled surface 222 may be configured to receive the second guide surface 332 of the first cross member 321, the third angled surface 223 may be configured to receive the third guide surface 333 of the second cross member 322, and the fourth angled surface 224 may be configured to receive the fourth guide surface 334 of the second cross member 322. In this manner, the drive spring 300 may be configured to engage the angled member 220 (when it is loaded onto the angled member 220) and apply a force to the needle safety shield 200 to bias the needle safety shield 200 in a distal direction relative to the needle hub 130. This causes the contact surface 215 of the needle safety shield 200 to engage the proximal surface 165 of the catheter adapter body 160, urging the catheter adapter body 160 in a distal direction relative to the needle hub 130. This, in turn, urges the catheter 170 in a distal direction relative to the introducer needle 120. In this manner, the pulling force experienced by the introducer needle 120 may be reduced and / or normalized in order to provide a uniform handling / feel that aids the practitioner in better guiding the catheter 170 and advancing or placing the catheter 170 within the patient's vasculature.

[0046] 4A-4C show various side views of the drive spring 300 as it is loaded onto the ramp member 220. FIG. 4A shows the drive spring 300 before it is loaded onto the ramp member 220. FIG. 4A also shows how the introducer needle 120 can be gripped between the first and second cross members 321, 322. In this embodiment, there is only a short length of the introducer needle 120 that is "unsupported" between the first and second cross members 321, 322 and the tip of the ramp protrusion 250. This design results in less bending and wobbling experienced by the introducer needle 120. FIG. 4B shows the drive spring 300 sliding across the ramp member 220 as it is loaded onto the ramp member 220, and FIG. 4C shows the drive spring 300 after it has been fully loaded onto the ramp member 220. FIG. 4C also shows how the first and second cross members 321, 322 fit within the first and second plateau portions 231, 232, respectively, of the tilting member 220 to keep the drive spring 300 fully loaded on the tilting member 220.

[0047] Figures 5A-6 show various views of a resilient member or drive spring 400 and an intermediate member or ramp member 500 according to alternative embodiments of the present disclosure. Specifically, Figure 5A is a top perspective view of the drive spring 400 as it is loaded onto the ramp member 500, Figure 5B is a side cross-sectional view of the drive spring 400 after it has been fully loaded onto the ramp member 500, and Figure 6 is a side cross-sectional view of an exemplary catheter assembly or catheter system 600 incorporating the drive spring 400 and ramp member 500 of Figures 5A and 5B.

[0048] The ramp member 500 may include a first ramp surface 521, a second ramp surface 522, a third ramp surface 523, a fourth ramp surface (not visible in FIGS. 5A-6), a first plateau portion 531, a second plateau portion 532, a first stop ridge 541, a second stop ridge 542, and a ramp protrusion 550 having a ramp needle opening 551 formed therethrough. The drive spring 400 may include a first spring arm 411, a second spring arm 412, and a first cross member 421 connecting the first spring arm 411 to the second spring arm 412. The drive spring 400 may also include a third spring arm 413, a fourth spring arm 414, and a second cross member 422 connecting the third spring arm 413 to the fourth spring arm 414. The second resilient portion 442 may couple the first spring arm 411 to the third spring arm 413, and the first resilient portion 441 may couple the second spring arm 412 to the fourth spring arm 414. The first and second resilient portions 441, 442 may each apply one or more biasing forces to the first and second cross members 421, 422 to urge the first and second cross members 421, 422 toward one another. In at least some embodiments, the first and second cross members 421, 422 may be configured to grip an introducer needle between the first and second cross members 421, 422 when the first and second cross members 421, 422 are urged toward one another. For example, first and second spring plates 451 and second spring plates (not visible in Figures 5A-6) may be formed on the first and second cross members 421, 422 to receive and / or grip an introducer needle between the first and second cross members 421, 422 when the first and second cross members 421, 422 are urged toward one another by the first and second resilient portions 441, 442.

[0049] As shown in FIG. 6 , the drive spring 400 may be coupled to the needle hub 130 and the ramp member 500 may be coupled to the needle safety shield 140. However, it will be appreciated that in at least some embodiments, the drive spring 400 may be coupled to the needle safety shield 140 and the ramp member 500 may be coupled to the needle hub 130. The drive spring 400 may be configured to engage the ramp member 500 and apply a force to the needle safety shield 140 to urge the needle safety shield 140 distally relative to the needle hub 130. This, in turn, causes the contact surface of the needle safety shield 140 to engage the proximal surface of the catheter adapter body 160, urging the catheter adapter body 160 distally relative to the needle hub 130. This, in turn, urges the catheter 170 distally relative to the introducer needle 120. In this way, the pulling forces experienced by the introducer needle 120 from other components of the catheter system 600 are reduced and / or normalized in order to provide a uniform operation and "feel" to the practitioner, which can assist the practitioner in better guiding and positioning the catheter 170 within the patient's vasculature.

[0050] 7 is a partial side cross-sectional view of an exemplary catheter assembly or catheter system 700 according to an alternative embodiment of the present disclosure. In general, the catheter system 700 may include an introducer needle 710 with a needle ridge 711, a needle hub 720 coupled to the introducer needle 710, an intermediate member 730 with a contact surface 715, a first resilient member 741, a first bearing member 781 coupled to the first resilient member 741, a second resilient member 742, a second bearing member 782 coupled to the second resilient member 742, a ramp member 750 with a first ramped surface 751 and a second ramped surface 752, a catheter adapter body 760 with a proximal surface 765, and a catheter 770 extending from a distal end of the catheter adapter body 760.

[0051] The catheter system 700 can function similarly to other catheter systems described herein. However, in at least some embodiments, the first and second bearing members 781, 782 may be configured to rotate relative to the first and second resilient members, respectively. In this manner, friction between the first resilient member 741 and the first angled surface 751 may be reduced, and friction between the second resilient member 742 and the second angled surface 752 may also be reduced. Additionally, the first and second resilient members 741, 742 may be coupled to the intermediate member 730, and the angled member 750 may be coupled to the needle hub 720, unlike other catheter system embodiments disclosed herein. In this aspect, the first and second resilient members 741, 742 may engage the first and second angled surfaces 751, 752 to apply a force to the intermediate member 730, urging the intermediate member 730 in a distal direction relative to the needle hub 720. This may cause the contact surface 715 of the intermediate member 730 to engage the proximal surface 765 of the catheter adapter body 760, urging the catheter adapter body 760 in a distal direction relative to the needle hub 720. This, in turn, may urge the catheter 770 in a distal direction relative to the introducer needle 710. In this manner, the pulling force experienced by the introducer needle 710 (from other components within the catheter system 700) may be reduced and / or normalized in order to provide a uniform pulling force to the practitioner to aid the practitioner in guiding the catheter 770 into the patient's vasculature.

[0052] 8 is a flow chart of a method 800 for inserting a catheter into a patient's blood vessel, according to some embodiments of the present disclosure. Method 800 may be facilitated by use of a catheter assembly or system including an introducer needle coupled to a needle hub, an intermediate member having a contact surface disposed at a distal end of the intermediate member, a resilient member coupled to one of the needle hub and the intermediate member, and a ramp member coupled to the other of the needle hub and the intermediate member.

[0053] The method 800 may begin at step 810 where a distal end of an introducer needle is inserted into a patient's blood vessel by a practitioner.

[0054] When the practitioner has inserted the distal end of the introducer needle into the patient's blood vessel, the method 800 may proceed to step 820, where the practitioner advances the intermediate member proximally relative to the introducer needle.

[0055] When the practitioner advances the intermediate member proximally relative to the introducer needle, the method 800 may proceed to step 830, where the resilient member engages the angled surface of the angled member to apply a force to the intermediate member, urging the intermediate member distally relative to the needle hub.

[0056] Once the resilient member engages the angled surface and applies a force to the intermediate member to urge the intermediate member in a distal direction relative to the needle hub, method 800 may proceed to step 840, where a contact surface of the intermediate member is engaged with a proximal surface of the catheter adapter body to urge the catheter adapter body in a distal direction relative to the needle hub.

[0057] Once the catheter adapter body has been urged distally relative to the needle hub, method 800 may proceed to step 850 of urging a catheter coupled to the catheter adapter body distally relative to the introducer needle. In some embodiments, a catheter coupled to the catheter adapter body may be urged distally relative to the introducer needle for purposes of inserting a distal end of the catheter into a blood vessel or for purposes of advancing the introducer needle further within the blood vessel.

[0058] Alternatively, or in addition, method 800 may proceed to any one or more of steps 860, 870, and / or 880. For example, once the catheter is urged distally relative to the introducer needle, method 800 may proceed to step 860 and / or step 870, where the needle hub and introducer needle are moved proximally relative to the catheter to completely or at least partially withdraw the introducer needle from the catheter. Once the introducer needle is at least partially withdrawn from the catheter, method 800 may further proceed to step 880, where the introducer needle is grasped between first and second cross members of the elastic member as the introducer needle is at least partially withdrawn from the catheter, and method 800 may end.

[0059] Any method disclosed herein includes one or more steps or actions for carrying out the described method. One or more of the method steps and / or actions may be omitted from any of the methods disclosed herein. Further, any of the method steps and / or actions may be interchanged with one another. In other words, the order and / or use of certain steps and / or actions may be modified, unless a specific order of steps or actions is required for proper operation of an embodiment.

[0060] It will be appreciated that any number of different drive spring configurations and / or styles may be utilized with the general concepts disclosed herein to reduce the initial tensile force imparted to an introducer needle in a given catheter system. For example, other drive spring configurations contemplated herein may include a helical spring configuration (not shown) that may be utilized to impart a force to an intermediate member to reduce the initial tensile force imparted to an introducer needle in a given catheter system.

[0061] Additionally, any number of ramped surfaces, configurations, and / or shapes are contemplated herein that achieve a desired force profile that optimally reduces and / or normalizes the pulling force applied to the introducer needle for a given catheter system without departing from the spirit or scope of the present application. Thus, the number of ramped surfaces, plateaus, and stop ridges, as well as their configurations and / or shapes, can be varied to fine-tune any number of parameters, including, but not limited to: (1) the timing of the release of the drive spring; (2) the smoothness of the actuation of the drive spring before / during its release and / or along its full range of motion; (3) adjusting the maximum and / or minimum force applied by the drive spring; (4) adjusting any transition characteristics of the drive spring force as it transitions between given maximum and minimum forces; (5) adjusting the average force applied by the drive spring (e.g., by adjusting the angle of the ramp and / or by adjusting the strength of the drive spring itself), etc.

[0062] It will also be noted that in at least some embodiments, the maximum driving force may be selected so as not to exceed the pulling force applied to the introducer needle by a given catheter system. In this way, unintentional self-advancement of the catheter may be avoided and / or advancement of the catheter at a more rapid rate than anticipated by the practitioner.

[0063] Reference throughout this specification to an "embodiment" or "said embodiment" means that a particular feature, structure, or characteristic described in connection with that embodiment is included in at least one embodiment. Thus, references or variations thereof mentioned throughout this specification do not necessarily all refer to the same embodiment. It is understood that any of the disclosed embodiments, or any portion(s) of the disclosed embodiments, can be combined together in any number of different ways.

[0064] Similarly, in the description of the above embodiments, it should be understood that various features may be grouped together in a single embodiment, drawing, or description thereof for the purpose of streamlining the disclosure. However, this format of disclosure should not be interpreted as reflecting an intention that any claim requires more features than are expressly recited in that claim. Rather, as the following claims reflect, inventive aspects lie in combinations of fewer than all features of any single such disclosed embodiment. Thus, the claims following the description of the present embodiments are expressly incorporated into this description of the present embodiments, with each claim standing on its own as a separate embodiment. This disclosure includes all permutations of the independent claims and their dependent claims.

[0065] The term "first" used in a claim with respect to a feature or element does not necessarily imply the presence of a second or additional such feature or element. Elements described in means-function form are intended to be construed pursuant to 35 U.S.C. §112, paragraph 6. It will be apparent to those skilled in the art that changes can be made to the details of the above-described embodiments without departing from the underlying principles described herein.

[0066] Standard medical directions, planes of reference, and descriptive terminology are employed herein. For example, anterior means toward the front of the body; posterior means toward the rear of the body; superior means toward the head; inferior means toward the feet; medial means toward the midline of the body; lateral means away from the midline of the body; axial means toward the central axis of the body; dorsal means away from the central axis of the body; ipsilateral means on the same side of the body; and contralateral means on the opposite side of the body. Sagittal plane refers to a plane that divides the body into left and right sides. Midsagittal plane is a plane that divides the body symmetrically. Coronal plane is a plane that divides the body into anterior and posterior parts. Transverse plane divides the body into upper and lower parts. These descriptive terms may be applied to living or inanimate bodies.

[0067] The phrases "connected," "coupled," "engaged with," and "in communication with" refer to any type of interaction between two or more entities, including mechanical, electrical, magnetic, electromagnetic, fluid, and thermal interaction. Two components may be functionally coupled even if they are not in direct contact with each other. The term "abutting" refers to items that are in direct physical contact with each other, although the items may not necessarily be attached together. The term "fluid communication" refers to two features that are connected such that fluid in one feature can pass to the other feature.

[0068] As defined herein, "substantially equal" means "equal to" or within about + or -10% relative variation from each other.

[0069] The word "exemplary" is used herein to mean "serving as an example, explanation, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. While various aspects of the embodiments are illustrated in the drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

[0070] While particular embodiments and applications of the present disclosure have been illustrated and described, it is to be understood that the appended claims are not limited to the precise configuration and components disclosed herein. Various modifications, changes and variations may be made in the arrangement, operation and details of the devices and systems disclosed herein, which will be apparent to those skilled in the art.

[0071] All examples and conditional statements described herein are intended for educational purposes to help the reader understand the invention and the concepts the inventor has contributed to further the art, and are not to be construed as being limited to such specifically described examples and conditions. Although the embodiments of the present disclosure have been described in detail, it should be understood that various changes, substitutions, and alterations can be made therein without departing from the spirit and scope of the present disclosure.

Claims

1. The catheter system 1. A needle assembly comprising: An introducer needle, and a needle assembly including a needle hub coupled to the introducer needle; a drive spring coupled to the needle hub, the drive spring comprising: an upper portion, said upper portion comprising: A first spring arm, A second spring arm, and an upper portion including a first cross member connecting the first spring arm to the second spring arm; A sub-portion, said sub-portion comprising: A third spring arm, A fourth spring arm, and a lower portion including a second cross member connecting the third spring arm to the fourth spring arm; A first elastic portion, and a second elastic portion; the second resilient portion connects the first spring arm to the third spring arm; the first resilient portion connects the second spring arm to the fourth spring arm; and a drive spring, the first and second resilient portions applying a biasing force to the first and second cross members to urge the first and second cross members toward one another; and 1. A needle safety shield, comprising: a contact surface disposed at a distal end of the needle safety shield, the needle safety shield configured to slidably receive the introducer needle therein; and a ramp member disposed at a proximal end of the needle safety shield, the ramp member comprising: a first angled surface configured to receive a first guide surface of the first cross member; a second angled surface configured to receive a second guide surface of the first cross member; a third angled surface configured to receive a third guide surface of the second cross member; and a fourth angled surface configured to receive a fourth guide surface of the second cross member; the drive spring engages the ramp member and applies a force to the needle safety shield, urging the needle safety shield distally relative to the needle hub; the contact surface of the needle safety shield engages a proximal surface of a catheter adapter body to bias the catheter adapter body distally relative to the needle hub; and a needle safety shield configured to bias a catheter protruding from a distal end of the catheter adapter body in the distal direction relative to the introducer needle; A catheter system comprising:

2. 2. The catheter system of claim 1, wherein the first and second cross members are configured to grip the introducer needle between the first and second cross members when the first and second cross members are biased together.

3. 2. The catheter system of claim 1, wherein the first angled surface comprises a first concave surface portion, the second angled surface comprises a second concave surface portion, the third angled surface comprises a third concave surface portion, and the fourth angled surface comprises a fourth concave surface portion.

4. 4. The catheter system of claim 3, wherein the first concave surface portion has a first radius, the second concave surface portion has a second radius, the third concave surface portion has a third radius, and the fourth angled surface portion has a fourth radius.

5. The catheter system of claim 4 , wherein the first radius, the second radius, the third radius, and the fourth radius are substantially equal to one another.

6. The catheter system of claim 1 , wherein the ramp member comprises at least one plateau portion.

7. The catheter system of claim 6 , wherein the ramp member comprises at least one stop ridge adjacent the at least one plateau portion.

8. A catheter assembly comprising: an introducer needle coupled to a needle hub; an intermediate member including a contact surface disposed at a distal end thereof, said intermediate member configured to slidably receive said introducer needle therein; a resilient member coupled to one of the needle hub and the intermediate member; and a ramp member coupled to the other of the needle hub and the intermediate member; the resilient member is configured to engage at least one ramped surface of the ramped member and apply a force to the intermediate member to urge the intermediate member in a distal direction relative to the needle hub; the contact surface of the intermediate member engages a proximal surface of a catheter adapter body to bias the catheter adapter body distally relative to the needle hub; and a catheter protruding from the distal end of the catheter adapter body is biased in the distal direction relative to the introducer needle.

9. The elastic member comprises a drive spring, the drive spring comprising: an upper portion, said upper portion comprising: A first spring arm, A second spring arm, and a first cross member connecting the first spring arm to the second spring arm; A sub-portion, said sub-portion comprising: A third spring arm, A fourth spring arm, and a second cross member connecting the third spring arm to the fourth spring arm; A first elastic portion, and A second elastic portion is provided. the second resilient portion connects the first spring arm to the third spring arm; the first resilient portion connects the second spring arm to the fourth spring arm; 9. The catheter assembly of claim 8, wherein the first and second resilient portions apply a biasing force to the first and second cross members to urge the first and second cross members toward one another.

10. 10. The catheter assembly of claim 9, wherein the first and second cross members are configured to grip the introducer needle between the first and second cross members when the first and second cross members are biased together.

11. The at least one sloping surface of the sloping member is a first angled surface configured to receive a first guide surface of the first cross member; a second angled surface configured to receive a second guide surface of the first cross member; a third angled surface configured to receive a third guide surface of the second cross member; and 10. The catheter assembly of claim 9, further comprising a fourth angled surface configured to receive a fourth guide surface of the second cross member.

12. The catheter assembly of claim 8 , wherein the at least one angled surface includes a concave surface portion having a first radius.

13. The catheter assembly of claim 12 , wherein the at least one sloping surface comprises a plateau portion.

14. The catheter assembly of claim 13 , wherein the at least one sloping surface comprises a stop ridge intermediate the concave surface portion and the plateau portion.

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