Catheter tip structure and manufacturing method

Abstract

The distal tip structure of a rapid insertion central venous catheter (RICC) is required to perform a function different from that of the remaining multi-lumen portion of the RICC catheter. As such, the catheter body can be formed from a first material and the distal tip structure can be formed from a second material. Forming the RICC catheter requires joining these two materials while maintaining a smooth abluminal surface. A bifurcated plug comprising the second material can be placed within the first or second lumen of the catheter body. A mandrel can be placed within the third lumen. The assembly can then be placed within a die and the bifurcated plug can be plastically deformed into the distal tip structure. Advantageously, only one structure is required to occlude the lumen and form the distal tip structure, reducing complexity and associated costs.

Description

[Technical field]

[0001] The present invention relates to a catheter tip structure and a method of manufacture. Summary of the Invention

[0002] Briefly summarized, embodiments disclosed herein relate to a distal tip structure for a catheter, such as a Rapidly Insertable Central Catheter (RICC), and associated methods of manufacture. The RICC system includes a catheter having a multi-lumen section defining two or more lumens, an access section defining a single lumen, and a dilator section disposed therebetween. The RICC catheter configuration allows a clinician to access the vasculature, dilate the access site, and place the multi-lumen section in a single step, reducing the introduction and removal of multiple tools to perform these steps separately. Forming a RICC catheter requires the joining of three distinct structures, the multi-lumen section, the dilator section, and the access section, while maintaining a smooth profile. Each of the three distinct structures is required to exhibit different mechanical properties to fulfill its role in the placement process. Disclosed herein is a method of manufacture for a distal tip structure for a RICC catheter.

[0003] Disclosed herein is a method of forming a catheter, comprising: extruding a multi-lumen section of a catheter body having a first catheter lumen and a second catheter lumen; and forming a distal tip structure of the catheter body, where forming the distal tip structure of the catheter body comprises disposing a first tine of a bifurcated plug within the first catheter lumen, disposing a second tine of the bifurcated plug within the second catheter lumen, a distal tip of the bifurcated plug extending distal to a distal end of the catheter body, and forming the bifurcated plug into the distal tip structure coupled to the multi-lumen section.

[0004] In some embodiments, the multi-lumen portion is formed from a first material and the bifurcated plug is formed from a second material different from the first material. In some embodiments, the first material comprises more compliant or softer durometer mechanical properties compared to the second material. In some embodiments, the distal tip structure comprises one or both of the dilator portion and the access portion. In some embodiments, forming the bifurcated plug into the distal tip structure further comprises placing a portion of the bifurcated plug and a distal end of the multi-lumen portion in a die and applying one or more of pressure, heat energy, radio frequency energy, or ultrasonic energy to plastically deform the bifurcated plug into the distal tip structure. In some embodiments, the method further comprises placing a mandrel in a third lumen of the multi-lumen portion to define a portion of the distal lumen in the distal tip structure. In some embodiments, the bifurcated plug comprises one of a rod or tube folded in half, with a first end defining a first tine and a second end defining a second tine.

[0005] Also disclosed herein is a method of forming a distal tip structure of a catheter, the method including: forming a catheter body having a first material and including a multi-lumen section defining a first lumen and a second lumen; placing a proximal end of a mandrel within the distal end of the first lumen; placing a portion of the mandrel, the distal end of the multi-lumen section, and a pellet of a second material different from the first material in a die; and plastically deforming the pellet around a portion of the mandrel to form a distal tip structure coupled to the distal end of the multi-lumen section.

[0006] In some embodiments, the first material is more compliant, elastically deformable, or softer in durometer compared to the second material. In some embodiments, the distal tip structure includes a dilator portion and a portion of the access portion. In some embodiments, the distal tip structure includes a dilator portion having a recess configured to receive a proximal portion of the access portion. In some embodiments, the method further includes coupling the proximal portion of the access portion to the recess with an adhesive, bonding, or welding.

[0007] A more particular description of the present disclosure will be provided by reference to specific embodiments thereof that are illustrated in the accompanying drawings. These drawings depict only typical embodiments of the invention and therefore should not be considered as limiting its scope. Exemplary embodiments of the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings. [Brief description of the drawings]

[0008] [Figure 1A] 1 illustrates a perspective view of a RICC system according to an embodiment disclosed herein. [Figure 1B] 1B shows a side view of a catheter of the RICC system of FIG. 1A according to an embodiment disclosed herein. [Diagram 2] 1C shows an enlarged detail of a distal portion of the catheter of FIG. 1B according to an embodiment disclosed herein. [Diagram 3] 3 shows a cross-sectional view of the distal portion of FIG. 2 according to an embodiment disclosed herein. [Figure 4] 3 shows a cross-sectional view of the distal portion of FIG. 2 according to an embodiment disclosed herein. [Diagram 5] 3 shows a cross-sectional view of the distal portion of FIG. 2 according to an embodiment disclosed herein. [Figure 6] 3 shows a cross-sectional view of the distal portion of FIG. 2 according to an embodiment disclosed herein. [Figure 7]1 illustrates an exemplary method of forming a distal tip structure of a catheter body according to embodiments disclosed herein. [Figure 8A] 1 illustrates an exemplary method of forming a distal tip structure of a catheter body according to embodiments disclosed herein. [Figure 8B] 1 illustrates an exemplary method of forming a distal tip structure of a catheter body according to embodiments disclosed herein. [Figure 8C] 1 illustrates an exemplary method of forming a distal tip structure of a catheter body according to embodiments disclosed herein. [Figure 9A] 1 illustrates an exemplary method of forming a distal tip structure of a catheter body according to embodiments disclosed herein. [Figure 9B] 1 illustrates an exemplary method of forming a distal tip structure of a catheter body according to embodiments disclosed herein. [Figure 9C] 1 illustrates an exemplary method of forming a distal tip structure of a catheter body according to embodiments disclosed herein. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Before disclosing some specific embodiments in more detail, it should be understood that the specific embodiments disclosed herein do not limit the scope of the concepts provided herein. It should also be understood that the specific embodiments disclosed herein may have features that can be easily separated from the specific embodiment and, optionally, combined with or substituted for features of any of the other embodiments disclosed herein.

[0010] With regard to the terms used herein, it should also be understood that these terms are intended to describe some particular embodiments, and that these terms do not limit the scope of the concepts provided herein. Ordinal numbers (e.g., first, second, third, etc.) are generally used to distinguish or identify different features or steps within a group of features or steps, and do not provide serial or numerical limitations. For example, the "first," "second," and "third" features or steps do not necessarily have to appear in that order, and a particular embodiment including such features or steps is not necessarily limited to three features or steps. Designations such as "left," "right," "up," "down," "front," "rear," etc. are for convenience and do not imply, for example, a particular fixed position, direction, orientation, etc. Instead, such designations are used to reflect, for example, a relative position, orientation, or direction. The singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

[0011] In the following description, the terms "or" and "and / or" as used herein should be interpreted as being inclusive or meaning any one or any combination. As an example, "A, B or C" or "A, B and / or C" means "any of the following: A, B, C, A and B, A and C, B and C, A, B and C." Exceptions to this definition occur only where combinations of elements, components, features, steps or acts are in some way inherently mutually exclusive.

[0012] For example, with respect to the "proximal," "proximal portion," or "proximal end portion" of a catheter disclosed herein, includes the portion of the catheter that is intended to be near the clinician when the catheter is used on a patient. Similarly, for example, the "proximal length" of a catheter includes the length of the catheter that is intended to be near the clinician when the catheter is used on a patient. For example, the "proximal end" of a catheter includes the end of the catheter that is intended to be near the clinician when the catheter is used on a patient. The proximal portion, proximal end portion, or proximal length of a catheter can include the proximal end of the catheter. However, the proximal portion, proximal end portion, or proximal length of a catheter need not include the proximal end of the catheter. That is, unless the context suggests otherwise, the proximal portion, proximal end portion, or proximal length of a catheter is not the terminal portion or terminal length of the catheter.

[0013] For example, with respect to the "distal," "distal portion," or "distal end portion" of a catheter disclosed herein, includes the portion of the catheter that is intended to be near or within the patient when the catheter is used with the patient. Similarly, for example, the "distal length" of a catheter includes the length of the catheter that is intended to be near or within the patient when the catheter is used with the patient. For example, the "distal end" of a catheter includes the end of the catheter that is intended to be near or within the patient when the catheter is used with the patient. The distal portion, distal end portion, or distal length of a catheter can include the distal end of the catheter. However, the distal portion, distal end portion, or distal length of a catheter need not include the distal end of the catheter. That is, unless the context suggests otherwise, the distal portion, distal end portion, or distal length of a catheter is not the terminal portion or terminal length of the catheter.

[0014] To assist in illustrating the embodiments described herein, as shown in Figure 1A, the longitudinal axis extends generally parallel to the axial length of the catheter, the lateral axis extends normal to the longitudinal axis, and the transverse axis extends normal to both the longitudinal and lateral axes.

[0015] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. 1A and 1B generally show details of an exemplary rapid insertion central venous catheter (RICC) placement system ("placement system") 100 including a needle 120, a guidewire 130, a syringe system 140, and a RICC catheter 150. The RICC catheter 150 may generally include a catheter body 152 supported at a proximal end by a catheter hub ("hub") 160. The hub 160 may include one or more extension legs 162 extending proximally therefrom. Each extension leg of the one or more extension legs 162 may be in communication with a lumen of the catheter body 152. The catheter body 152 may include an access portion 154, a multi-lumen portion 156, and a dilator portion 158 disposed therebetween. The guidewire 130 may extend through a lumen of the RICC catheter 150 from a proximal end of the extension leg 162 to a distal tip of the access portion 154.

[0016] In an exemplary method of placing the RICC catheter 150, the needle 120 can be urged distally towards the patient to access the vasculature and create an insertion site. The syringe system 140 or similar device can withdraw fluid flow proximally through the needle lumen 122 to observe color and / or pulsatile flow and confirm proper vasculature access. Once successful access to the vasculature is confirmed, the guidewire 130 can be advanced through the needle lumen 122 into the vasculature to maintain patency of the insertion site. The needle 120 and syringe system 140 assembly can then be withdrawn proximally. In one embodiment, the distal tip of the guidewire 130 can reside within the needle lumen 122 during venipuncture to facilitate access to the vasculature and maintain patency of the insertion site once venous access is confirmed.

[0017] The RICC 150 may then be advanced over the guidewire 130 and into the vasculature. The access portion 154 of the RICC 150 has only a single lumen and defines a relatively small outer diameter and may be passed over the guidewire 130 into the vasculature to secure the insertion site. The dilator portion 158 then dilates the insertion site to allow the relatively larger diameter multi-lumen portion 156, defining two or more lumens, to enter the vasculature. Once the RICC 150 is positioned, the guidewire 130 may be withdrawn proximally.Further details and embodiments of the RICC system 100 can be found in, for example, U.S. Pat. No. 10,376,675, U.S. Pat. Appl. Pub. No. 2019 / 0255294, U.S. Pat. Appl. Pub. No. 2021 / 0069471, U.S. Pat. Appl. Pub. No. 2021 / 0085927, U.S. Pat. Appl. Pub. No. 2021 / 0113809, U.S. Pat. Appl. Pub. No. 2021 / 0113810, U.S. Pat. Appl. Pub. No. 2021 / 0121661, U.S. Pat. Appl. Pub. No. 2021 / 02288, and U.S. Pat. No. 43, U.S. Patent Application Publication No. 2021 / 0283368, U.S. Patent Application Publication No. 2021 / 0283381, U.S. Patent Application Publication No. 2021 / 0322729, U.S. Patent Application Publication No. 2021 / 0330941, U.S. Patent Application Publication No. 2021 / 0330942, U.S. Patent Application Publication No. 2021 / 0361915, U.S. Patent Application Publication No. 2021 / 0379336, U.S. Patent Application Publication No. 2021 / 0402142, U.S. Patent Application Publication No. US Patent Application Publication No. 2021 / 0402149, US Patent Application Publication No. 2021 / 0402153, US Patent Application Publication No. 2021 / 0121667, US Patent Application Publication No. 2022 / 0001138, US Patent Application Publication No. 2022 / 0032013, US Patent Application Publication No. 2022 / 0032014, US Patent Application Publication No. 2022 / 0062528, US Patent Application Publication No. 2022 / 0126064, US Patent Application Publication No. 2022 / 0152368 , U.S. Patent Application Publication No. 2022 / 0176081, U.S. Patent Application Publication No. 2022 / 0176082, U.S. Patent Application Publication No. 2022 / 0193376, U.S. Patent Application Publication No. 2022 / 0193377, U.S. Patent Application Publication No. 2022 / 0193378, U.S. Patent Application Publication No. 2022 / 0193379, and U.S. Patent Application Publication No. 2022 / 0296862, each of which is incorporated by reference in its entirety.

[0018] As described herein, different portions of the RICC catheter 150 are required to perform different functions and therefore must exhibit different mechanical properties. For example, the access portion 154 and / or the dilator portion 158 may include a material with stiffer mechanical properties or harder durometer compared to the multi-lumen portion 156. As such, the access portion 154 and the dilator portion 158 can withstand greater axial forces without kinking or collapsing as the portions are forced distally to form and expand the insertion site. The multi-lumen portion 156 may be formed from a relatively softer or more flexible material in durometer to easily navigate tortuous vascular pathways. Forming the RICC catheter 150 requires joining these different structures formed from different materials while maintaining a smooth abluminal surface.

[0019] FIG. 2 shows further details of the distal portion of the RICC catheter 150, including the access portion 154, the dilator portion 158, and the distal portion of the multi-lumen portion 156. In one embodiment, the multi-lumen portion 156 can include a proximal lumen 114A terminating at a proximal lumen opening 116A and an intermediate lumen 114B terminating at an intermediate lumen opening 116B. Each of the proximal lumen opening 116A and the intermediate lumen opening 116B can extend through a sidewall of the multi-lumen portion 156. Each of the proximal lumen opening 116A and the intermediate lumen opening 116B can be disposed proximal to the dilator portion 158. In one embodiment, the proximal lumen opening 116A can be disposed proximal to the intermediate lumen opening 116B. In one embodiment, the proximal lumen opening 116A and the intermediate lumen opening 116B can be disposed equidistant from the catheter hub 160.

[0020] 3 illustrates a cross-sectional view of the access portion 154 at position "A" in FIG. 2. As shown, the access portion 154 can define a single lumen and a relatively small outer diameter. The distal lumen 114C of the RICC catheter 150 can extend to the distal tip 118 of the RICC catheter 150 and can communicate with the distal lumen opening 116C.

[0021] FIG. 4 is a cross-sectional view of the junction between access portion 154 and dilator portion 158 at position "B" of FIG. 2, with a portion of access portion 154 received within dilator portion 158.

[0022] 5 is a cross-sectional view of the dilator portion 158 at position "C" in FIG. 2, where the axis of the distal lumen 114C is offset from the axis of the dilator portion 158 as the distal lumen 114 transitions between the multi-lumen portion 156 and the access portion 154.

[0023] FIG. 6 is a cross-sectional view of multi-lumen section 156 at location "D" or "E" of FIG. 2, showing proximal lumen 114A, intermediate lumen 114B, and distal lumen 114C. Tip formation method FIG. 7 illustrates an exemplary method of manufacturing a catheter 150 including a distal tip structure 170 having one or both of an access portion 154 and a dilator portion 158. In an exemplary method of joining the distal tip structure 170 to the multi-lumen portion 156 to form the catheter body 152 (referred to as "tipping"), the multi-lumen portion 156 can be formed to have one or more lumens 114. In one embodiment, the multi-lumen portion 156 can be extruded and trimmed to a desired length. However, other methods of forming the multi-lumen portion 156 are also contemplated. As shown in FIG. 7, a three-lumen multi-lumen portion 156 is provided that includes a first (proximal) lumen 114A, a second (middle) lumen 114B, and a third (distal) lumen 114C. However, other single or multi-lumen catheters 150 are also contemplated. It should be noted that the lumens 114A, 114B, 114C of the multi-lumen section 156 may be arranged radially about a central axis of the multi-lumen section 156, as shown in Figure 6. In Figure 7, the lumens 114A, 114B, 114C are shown adjacent to one another for clarity, however, other configurations of the multi-lumen catheter 150 are contemplated.

[0024] In one embodiment, plugs 252 can be disposed in one or more lumens 114. For example, a first plug 252A can be disposed in a distal end of the first lumen 114A, and a second plug 252B can be disposed in a distal end of the second lumen 114B. A distal tip 254 of the plug 252 can be aligned with the distal end 218 of the multi-lumen portion 156. Optionally, the distal tip 254 of the plug 252 can be trimmed to align with the distal end 218 of the multi-lumen portion 156.

[0025] The distal tip structure 170 can then be bonded to the distal end 218 of the multi-lumen portion 156 using adhesives, bonding, solvent bonding, welding, or the like. The lumen of the distal tip structure 170 can be aligned with the lumen of the multi-lumen portion 156 to form a distal lumen 114C that extends to a distal lumen opening 116C. A first plug 252A can seal the distal end of the proximal lumen 114A, and a second plug 252B can seal the distal end of the intermediate lumen 114B, proximal to the dilator portion 158. The proximal lumen opening 116A can then be formed through the wall of the multi-lumen portion 156 to communicate with the proximal lumen 114A. The intermediate lumen opening 116B can then be formed through the wall of the multi-lumen portion 156 to communicate with the intermediate lumen 114B.

[0026] 8A-8C illustrate an exemplary method of forming a catheter 150 having a distal tip structure 170 including one or more of a dilator portion 158 and an access portion 154. As shown in FIG 8A, a multi-lumen portion 156 of a catheter body 152 is formed to include one or more lumens 114 as described herein. In one embodiment, the multi-lumen portion 156 can be formed from a first material.

[0027] In one embodiment, a bifurcated plug 180 can be provided that includes a second material different from the first material and includes one or more teeth 182. As shown in FIG. 8A, the bifurcated plug 180 can include a first tooth 182A and a second tooth 182B. The first tooth 182A can be disposed within the first lumen 114A, and the second tooth 182B can be disposed within the second lumen 114B. In one embodiment, the bifurcated plug 180 can include a bifurcated polymer rod or tube with a first end defining the first tooth 182A and a second end defining the second tooth 182B. Note that a distal end of the bifurcated plug 180 can extend distal to the distal end 218 of the multi-lumen portion 156. In one embodiment, the proximal end of the mandrel 240 can be disposed within the third lumen 114C and can define a path such that a portion of the distal lumen 114C extends from the multi-lumen portion 156 to the access portion 154.

[0028] As shown in FIG. 8B, the distal end 218 of the multi-lumen section 156 can include one or both of the bifurcated plug 180 and the mandrel 240 and can be disposed within the die 260. Energy (thermal energy, radio frequency (RF) energy, ultrasound, etc.) and / or pressure can be applied to the assembly of the distal end 218 of the multi-lumen section 156 and the bifurcated plug 180 to plastically deform the bifurcated plug 180 into at least a portion of the distal tip structure 170. The mandrel 240 can define a portion of the distal lumen 114C through which the mandrel 240 extends. In one embodiment, the distal tip structure 170 can define one or both of the dilator portion 158 and the access portion 154. In one embodiment, the distal tip structure 170 can include the dilator portion 158 and can define a recess configured to receive the proximal end of the access portion 154. Optionally, access portion 154 can be formed of a third material that is different from both the first and second materials and that exhibits different mechanical properties, durometer, etc. The proximal end of access portion 154 can then be coupled to dilator portion 158 using adhesives, bonding, welding, etc.

[0029] Advantageously, the material of the bifurcated plug 180 used to occlude the proximal and intermediate lumens 114A, 114B can be used to form the dilator portion 158. In this manner, only a single structure is required to occlude the lumens and form the distal tip structure 170, rather than two or more separate structures. This simplifies the manufacturing process and reduces associated costs.

[0030] In one embodiment, as shown in Figures 9A-9C, an assembly of a multi-lumen section 156 and a mandrel 240 can be provided as described herein. The multi-lumen section 156 can be formed from a first material. The multi-lumen section 156 can include one or more plugs 252. The assembly of the multi-lumen section 156, the plugs 252 and the mandrel 240 is then placed in a die 260 along with a pellet 230 of a polymeric material formed from a second material in the die 260. Energy (heat, RF, ultrasonic, etc.) and / or pressure can be applied to the assembly of the distal end 218, the mandrel 240 and the pellet 230 to plastically deform the pellet 230 into a distal tip structure 170.

[0031] In one embodiment, the multi-lumen portion 156 can be formed from a first material and the plug 252 and / or pellet 230 can be formed from a second material that is different from the first material. In one embodiment, the second material can exhibit different mechanical properties than the first material. In one embodiment, one of the first material, the second material, or the third material can be a plastic, polymer, polyurethane, composite, elastomer, or the like. In one embodiment, the second material can exhibit stiffer or harder mechanical properties relative to the first material, which can exhibit softer or softer mechanical properties in durometer. In one embodiment, the third material can exhibit higher or lower stiffness or higher or lower durometer relative to one or both of the first and second materials.

[0032] Some specific embodiments are disclosed herein, and although the specific embodiments are disclosed in some detail, the specific embodiments are not intended to limit the scope of the concept provided herein. Additional adaptations and / or modifications may be apparent to those skilled in the art, and the broader aspects also encompass these adaptations and / or modifications. Thus, one may deviate from the specific embodiments disclosed herein without departing from the scope of the concept provided herein.

Claims

1. A method of forming a catheter extruding a multi-lumen portion of a catheter body having a first catheter lumen, a second catheter lumen, and a third catheter lumen; forming a distal tip structure coupled to the multi-lumen portion of the catheter body, wherein forming a distal tip structure coupled to the multi-lumen portion of the catheter body comprises: placing a first tine of a bifurcated plug within the first catheter lumen; disposing a second tine of the bifurcated plug within the second catheter lumen, the distal tip of the bifurcated plug extending distally of the distal end of the catheter body; and forming a distal tip of the bifurcated plug in the distal tip structure of a catheter, thereby occluding the first and second catheter lumens at the distal end of the catheter body and extending the third catheter lumen from the distal end of the catheter body through the distal tip structure of the catheter.

2. The method of claim 1 , wherein the multi-lumen portion of the catheter body is formed from a first material and the distal tip structure of the catheter is formed from a second material that is different from the first material.

3. The method of claim 2 , wherein the first material is more flexible or has a softer durometer than the second material.

4. The method of any one of claims 1 to 3, wherein the distal tip structure of the catheter includes a dilator portion, an access portion, or both.

5. 4. The method of claim 1, wherein forming the distal tip of the bifurcated plug into the distal tip structure of the catheter further comprises: placing a portion of the bifurcated plug and the distal end of the catheter body in a die; and applying one or more of pressure, heat energy, radio frequency energy, or ultrasonic energy to plastically deform the distal tip of the bifurcated plug into the distal tip structure of the catheter.

6. 4. The method of claim 1, further comprising: disposing a mandrel within a third lumen of a multi-lumen portion of the catheter body to define the third catheter lumen within the distal tip structure when forming the distal tip of the bifurcated plug in the distal tip structure of the catheter.

7. 4. The method of claim 1, wherein the bifurcated plug comprises one of a rod or a tube bifurcated in half, a first end defining the first tooth and a second end defining the second tooth.

8. 1. A method of forming a distal tip structure of a catheter, comprising: forming a catheter body from a first material including a multi-lumen portion defining a first lumen and a second lumen; placing a proximal end of a mandrel within the distal end of the first lumen; placing a portion of the mandrel, a distal end of the multilumen portion of the catheter body, and a pellet of a second material different from the first material into a die; and plastically deforming the pellet about a portion of the mandrel to form the distal tip structure of a catheter coupled to a distal end of a multi-lumen section of the catheter body, thereby occluding the second lumen at the distal end of the catheter body and extending the first lumen from the distal end of the catheter body through the distal tip structure of the catheter.

9. The method of claim 8 , wherein the first material is more flexible, elastically deformable, or has a softer durometer than the second material.

10. The method of claim 8 or 9, wherein the distal tip structure of the catheter includes a dilator section and a portion of an access section.

11. 10. The method of claim 8 or 9, wherein the distal tip structure of the catheter includes a dilator portion having a recess configured to receive a proximal portion of an access portion.

12. The method of claim 11 , further comprising coupling a proximal portion of the access portion with a recess in the dilator portion using adhesive, bonding, or welding.

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