Catheter and method of manufacturing same

Abstract

A rapid insertion central venous catheter ("RICC") and method are disclosed. The RICC (100) can include a first section (130) of a first polymeric material at a distal portion of the catheter tube, a second section (132) of a second polymeric material proximal to the first section, and a tapered junction (134) therebetween. The first polymeric material has a first durometer. The second polymeric material has a second, lower durometer. The junction is formed from the second polymeric material or a third polymeric material having a third durometer closer to the second durometer than the first durometer. The first section has a proximal section disposed within a junction receptacle. The abluminal surface of the distal section of the junction smoothly transitions to the abluminal surface of the proximal section of the first section without any edges that may catch on the skin when the RICC is inserted into a patient's insertion site.

Description

[Technical Field]

[0001] The present invention relates to a rapid insertion central venous catheter and a method for making the same. [Background technology]

[0002] Central venous catheters (CVCs) are formed from materials with relatively low durometers, which contributes to CVCs' lack of column buckling strength. Due to this lack of column buckling strength, CVCs are typically introduced into a patient's body and advanced through the vasculature using the Seldinger technique. The Seldinger technique utilizes many steps and medical devices (e.g., needles, scalpels, guidewires, introducer sheaths, dilators, CVCs, etc.). Although the Seldinger technique is effective, the many steps are time-consuming, and the handling of numerous medical devices is cumbersome, all of which can potentially cause trauma to the patient. Additionally, due to the large number of medical devices that need to be replaced during the multiple steps of the Seldinger technique, the potential for contact contamination is relatively high. Therefore, there is a need to reduce the number of steps and medical devices involved in introducing a catheter into a patient's body and advancing the catheter through the vasculature.

[0003] Disclosed herein is a rapidly inserted central catheter ("RICC") and method including a catheter assembly that addresses at least the above. Summary of the Invention

[0004] In some embodiments, the RICC disclosed herein includes a first section of catheter tubing, a second section, and a tapered junction. The first section of the catheter tubing is formed from a first polymeric material having a first durometer. The first section is located in a distal section of the catheter tubing. The second section of the catheter tubing is formed from a second polymeric material having a second durometer that is lower than the first durometer. The second section is located in the distal section of the catheter tubing and proximal to the first section. The junction section of the catheter tubing is formed from the second polymeric material, a third polymeric material having a third durometer that is closer to the second durometer than the first durometer, or a combination thereof. The first section of the catheter tubing is disposed within a receptacle of the junction and has a proximal section fixedly coupled to the receptacle. The abluminal surface of the distal portion of the junction transitions smoothly to the abluminal surface of the proximal portion of the first section without any edges that may catch on the skin when the RICC is inserted into the patient's insertion site.

[0005] In some embodiments, the edge comprises a solvent-interdiffused polymeric material between the first polymeric material and the polymeric material of the joint.

[0006] In some embodiments, the first polymeric material is polytetrafluoroethylene, polypropylene, or polyurethane. In some embodiments, the second polymeric material is polyvinyl chloride, polyethylene, polyurethane, or silicone.

[0007] In some embodiments, the RICC is a three-lumen catheter having a primary lumen, a secondary lumen, and a tertiary lumen. The primary lumen has a primary lumen opening at the distal end of a first section of the catheter tubing. The secondary lumen has a secondary lumen opening on a side of a second section of the catheter tubing. The tertiary lumen has a tertiary lumen opening on a side of the second section proximal to the secondary lumen opening.

[0008] In some embodiments, the junction includes a third polymeric material that is radio frequency ("RF") welded to the second portion of the catheter tube, and only the primary lumen extends from the second portion through the junction to the first portion.

[0009] In some embodiments, the RICC has sufficient column strength to prevent buckling of the catheter tube when inserted into a patient's insertion site and advanced through the patient's vasculature.

[0010] Also disclosed in some embodiments is a method for fabricating a RICC, the method including a mandrel insertion step, a first catheter tube insertion step, a melting step, a pushing step, a first removal step, and a second removal step. The mandrel insertion step includes inserting a stepped mandrel into a primary lumen of a second portion of the catheter tube. The mandrel insertion step forms a mandrel-mounted catheter tube. The first catheter tube insertion step includes inserting the mandrel-mounted catheter tube into a cavity of an RF welding die so that the distal end of the mandrel-mounted catheter tube does not reach the end of the RF welding die. The melting step includes melting a polymer material of the mandrel-mounted catheter tube, a supplemental polymer material, or a combination thereof, in the RF welding die by heating the RF welding die. The melted polymer material conforms to the cavity of the RF welding die during the melting step to form a welded joint to the second portion of the catheter tube. The melting step forms a soft portion of the catheter tube including the second portion of the catheter tube and the joint. The pushing step includes forcing the mandrel and the flexible portion of the catheter tube attached to the mandrel together into the end of the RF welding die as excess molten polymer material seeps out through an exit hole in the end of the RF welding die. The pushing action in the pushing step cuts off the excess molten polymer material from the distal end of the flexible portion of the catheter tube. The first removal step includes removing the mandrel and the flexible portion of the catheter tube attached to the mandrel together from the RF welding die. The second removal step includes removing the mandrel from both the primary lumen of the second portion of the catheter tube and the receptacle of the junction.

[0011] In some embodiments, the method further includes a second catheter tube insertion step and a bonding step. The second catheter tube insertion step includes inserting a proximal portion of the rigid section of the catheter tube into a receptacle of the junction. The bonding step includes securely bonding the rigid and flexible sections of the catheter tube together such that an abluminal surface of the distal section of the junction transitions smoothly to an abluminal surface of the proximal section of the first section without edges that may catch on the skin when the RICC is inserted into an insertion site in a patient.

[0012] In some embodiments, the method further comprises a solvent application step, which comprises applying a solvent to the proximal portion of the rigid section of the catheter tube, the receptacle of the junction, or both, which occurs before the second catheter tube insertion step.

[0013] In some embodiments, the method further includes a first catheter tube obtaining step or a first catheter tube extruding step, wherein the first catheter tube obtaining step or the first catheter tube extruding step includes obtaining or extruding, respectively, a first portion of the catheter tube, the first portion corresponding to a rigid portion of the catheter tube.

[0014] In some embodiments, a first section of the catheter tubing is formed from a first polymeric material having a first durometer, a second section of the catheter tubing is formed from a second polymeric material having a second durometer that is lower than the first durometer, and a joint of the catheter tubing is formed from the second polymeric material, a supplemental polymeric material, or a combination thereof, where the supplemental polymeric material is a third polymeric material having a third durometer that is closer to the second durometer than the first durometer.

[0015] In some embodiments, the method further includes a second catheter tube obtaining step or a second catheter tube extruding step, wherein the second catheter tube obtaining step or the second catheter tube extruding step includes obtaining or extruding, respectively, a second portion of catheter tube, the second portion of catheter tube being multi-lumen, having one or more additional lumens relative to the primary lumen.

[0016] In some embodiments, the method further comprises a polymer rod insertion step, which comprises inserting one or more polymer rods into the one or more additional lumens prior to the melting step, wherein the one or more polymer rods provide a supplemental polymer material.

[0017] In some embodiments, the method further comprises a sacrificial tube placement step, which comprises placing a sacrificial polymer tube over the stepped mandrel before or after forming the mandrel-mounted catheter tube, wherein the sacrificial polymer tube provides a supplemental polymer material.

[0018] Also disclosed herein, in some embodiments, is a method of using a RICC assembly, the method including an insertion site preparation step, a RICC insertion step, and a RICC advancement step. The insertion site preparation step includes preparing an insertion site for accessing a patient's vasculature using an introducer needle positioned within the primary lumen of the RICC. The RICC insertion step includes inserting a distal portion of a catheter tube of the RICC into the insertion site beyond a tapered junction between a first portion of the catheter tube and a second portion of the catheter tube, such that an edge between the first portion and the junction does not catch on the patient's skin during the RICC insertion step. The RICC advancement step includes advancing the distal portion of the catheter tube through the patient's vasculature without using the Seldinger technique.

[0019] In some embodiments, the method further includes, after the insertion site creation step, a needle withdrawal step of withdrawing the introducer needle from the primary lumen of the RICC and inserting at least a portion of the distal portion of the catheter tube into the insertion site.

[0020] In some embodiments, the insertion site is in the right subclavian vein or the right internal jugular vein. In some embodiments, the RICC advancement step includes advancing a distal portion of the catheter tube through the right subclavian vein, the right internal jugular vein, or the right brachiocephalic vein into the superior vena cava.

[0021] These and other features of the concepts provided herein will become more apparent to those skilled in the art in view of the accompanying drawings and the following description, which disclose in more detail certain embodiments of such concepts. [Brief explanation of the drawings]

[0022] [Figure 1] 1 illustrates a RICC assembly according to some embodiments. [Figure 2] 2 illustrates a distal portion of the catheter tube of the RICC of FIG. 1, according to some embodiments. [Figure 3] 3 shows a first cross-section of the catheter tube of FIG. 2 according to some embodiments. [Figure 4] 3 shows a second cross section of the catheter tube of FIG. 2 according to some embodiments. [Figure 5] 3 illustrates a third cross-section of the catheter tube of FIG. 2 according to some embodiments. [Figure 6] 3 illustrates a fourth cross-section of the catheter tube of FIG. 2 according to some embodiments. [Figure 7A] 2 illustrates a polymer rod insertion step of a first method for fabricating the RICC of FIG. 1 according to some embodiments. [Figure 7B] 2 illustrates a mandrel insertion step of a first method of making the RICC of FIG. 1 according to some embodiments. [Figure 7C]2A-2C illustrate melting and indentation steps of a first method of making the RICC of FIG. 1 according to some embodiments. [Figure 8A] 2 illustrates a sacrificial tube placement step of a second method of fabricating the RICC of FIG. 1 according to some embodiments. [Figure 8B] 2 illustrates a mandrel insertion step of a second method of making the RICC of FIG. 1 according to some embodiments. [Figure 8C] 2 illustrates melting and indentation steps of a second method for making the RICC of FIG. 1 according to some embodiments. [Figure 9] 2A-2C show detailed views of the melting and pressing steps of either the first or second method of making the RICC of FIG. 1 according to some embodiments. [Figure 10] 10 illustrates a second catheter tube insertion and bonding step of a method according to some embodiments. DETAILED DESCRIPTION OF THE INVENTION

[0023] 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 are readily separable from the specific embodiment and that, optionally, can be combined with or substituted for features of any of the other embodiments disclosed herein.

[0024] Regarding the terms used herein, it should also be understood that these terms are intended to describe certain specific embodiments and 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, "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," "top," "bottom," "front," and "back" are for convenience and do not imply, for example, a specific fixed location, direction, or orientation. Instead, such designations are used, for example, to reflect relative location, orientation, or direction. The singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

[0025] For example, references to the "proximal," "proximal portion," or "proximal end portion" of a catheter disclosed herein include the portion of the catheter 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 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 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.

[0026] For example, references to the "distal," "distal portion," or "distal end portion" of a catheter disclosed herein include the portion of the catheter intended to be near or within a patient when the catheter is in use with the patient. Similarly, for example, the "distal length" of a catheter includes the length of the catheter intended to be near or within a patient when the catheter is in use with the patient. For example, the "distal end" of a catheter includes the end of the catheter intended to be near or within a patient when the catheter is in use 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.

[0027] 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. As discussed above, there is a need to reduce the number of steps and medical devices involved in introducing a catheter into a patient's body and advancing the catheter within the patient's vasculature. Disclosed herein is a RICC and method thereof that addresses the above need.

[0028] In addition to the need for such a RICC and method thereof, there is also a need to overcome certain artifacts in the fabrication of the RICC. For example, although a RICC may be multi-lumen, it can transition to a single-lumen portion at its distal portion, but this transition presents significant challenges in fabricating the RICC without creating edges or ridges that can catch on the patient's skin around the insertion site and prevent the RICC from being inserted. Accordingly, a RICC and method thereof that addresses the aforementioned needs is also disclosed herein. Rapid insertion central venous catheter FIG. 1 illustrates a RICC assembly 100 according to some embodiments.

[0029] As shown, the RICC assembly 100 includes a RICC 102, an introducer needle 104, an access guidewire 106, and a steering guidewire 108, which are coupled together in the ready-to-deploy state of the RICC assembly 100. Each of the above components of the RICC assembly 100 will be described in turn in the following paragraphs, although there will be some overlap between the paragraphs relating to the RICC 102, the introducer needle 104, the access guidewire 106, and the steering guidewire 108 given their interrelationship in the RICC assembly 100.

[0030] The RICC 102 may be a single-lumen or multi-lumen RICC (e.g., a two-lumen RICC, a three-lumen RICC, a four-lumen RICC, a five-lumen RICC, a six-lumen RICC, etc.). Indeed, the RICC 102 shown in FIG. 1 is a three-lumen RICC, including a set of three lumens. Such a set of three lumens includes a primary lumen 110 (e.g., a distal lumen), a secondary lumen 112 (e.g., an intermediate lumen), and a tertiary lumen 114 (e.g., a proximal lumen) formed from the fluidly connected portions of the three catheter tube lumens, three hub lumens, and three extension leg lumens. (See FIGS. 2 and 3-6.) The RICC 102, whether single-lumen or multi-lumen, includes at least a primary lumen 110. The primary lumen 110 typically extends from the proximal end to the distal end of the RICC 102, such as from the opening of a corresponding Luer connector to a primary lumen opening 116 at the distal end of the catheter tube 124 (e.g., a rigid portion of the catheter tube 124 or a first portion of the catheter tube 124), as described below. If the RICC 102 has two or more lumens, the RICC 102 also includes at least a secondary lumen 112. The secondary lumen 112 typically extends from the proximal end to a distal portion of the RICC 102, such as from the opening of a corresponding Luer connector to a secondary lumen opening 118 at the distal portion of the catheter tube 124 proximal to the primary lumen opening 116 (e.g., a flexible portion of the catheter tube 124 or a second portion of the catheter tube 124). If the RICC 102 has three or more lumens, the RICC 102 further includes at least a tertiary lumen 114. The tertiary lumen 114 generally extends from the proximal end to a distal portion of the RICC 102, such as from the opening of a corresponding Luer connector to a tertiary lumen opening 120 in a distal portion of the catheter tube 124 proximal to the secondary lumen opening 118 (e.g., in a flexible portion of the catheter tube 124 or a first portion of the catheter tube 124). Notwithstanding the above, the secondary lumen 112 and the tertiary lumen 114 can extend slightly distal to the secondary lumen opening 118 and the tertiary lumen opening 120, respectively, due to different manufacturing methods. (See FIGS. 2, 5, and 6.) The RICC 102, as shown, has an introduction opening 122 that is adapted solely for insertion of the introducer needle 104 therethrough for coupling the RICC 102 and the introducer needle 104 within the RICC assembly 100. However, the RICC 102 need not include a dedicated introduction opening such as the introduction opening 122. Indeed, the secondary lumen opening 118 or the tertiary lumen opening 120 can function as the introduction opening 122 in some embodiments, which requires a different mode of coupling the RICC 102 and the introducer needle 104, as described below. Alternatively, if desired, such as when the RICC 102 is single-lumen, the introduction opening can be created by puncturing the catheter tube 124 with the introducer needle 104.

[0031] The RICC 102 further has an introducer lumen that coincides with the distal portion of the primary lumen 110. In other words, the introducer lumen is the introducer portion of the primary lumen 110 of the RICC 102. In the RICC 102, the introducer lumen is the distal portion of the primary lumen 110 extending from the introducer opening 122 to the primary lumen opening 116. The introducer opening 122 may be distal to the secondary lumen opening 118, between the secondary lumen opening 118 and the tertiary lumen opening 120, or proximal to the tertiary lumen opening 120, and opens directly into the proximal end of the introducer portion of the primary lumen 110 of the RICC 102. In a RICC that does not have an introducer opening 122, the introducer lumen is the distal portion of the primary lumen 110 extending from the secondary lumen opening 118, the tertiary lumen opening 120, or the puncture made by the introducer needle 104 to the primary lumen opening 116. Whether the introducer lumen extends from the secondary lumen opening 118, the tertiary lumen opening 120, or the puncture depends on which of the aforementioned openings accommodates the introducer needle 104. Neither the secondary lumen opening 118 nor the tertiary lumen opening 120 opens directly into the proximal end of the introducing portion of the RICC's primary lumen 110 without the introducer opening 122. Instead, the introducer needle 104 penetrates a partition 123 between the secondary lumen 112 or tertiary lumen 114 and the primary lumen 110 via the secondary lumen opening 118 or the tertiary lumen opening 120, respectively.

[0032] The RICC 102 includes a catheter tube 124 , a catheter hub 126 , and one or more extension legs 128 . Figure 2 shows a distal portion of the catheter tube 124 of the RICC 102 of Figure 1, according to some embodiments. Figures 3-6 show various cross sections of the catheter tube 124, according to some embodiments.

[0033] The catheter tube 124 includes a rigid portion and a flexible portion, and "rigid" and "flexible" are used in a relative sense in that the rigid portion of the catheter tube 124 is rigider than the flexible portion of the catheter tube 124. Similarly, the flexible portion of the catheter tube 124 is flexibleer than the rigid portion of the catheter tube 124. The rigid portion of the catheter tube 124 includes a first portion 130 at the distal portion of the catheter tube 124, and the flexible portion of the catheter tube 124 includes a second portion 132 that extends from the proximal portion of the catheter tube 124 to the distal portion of the catheter tube 124 but proximal to the first portion 130. Notwithstanding the tapered junction 134 of the catheter tube 124 that includes the proximal portion of the rigid portion of the catheter tube 124 of the RICC 102, the flexible portion of the catheter tube 124 is generally considered to include the junction 134 due to its structure. The above-described configurations of the first portion 130 of the catheter tube 124, the second portion 132 of the catheter tube 124, and the joint 134 together have sufficient column strength to prevent buckling of the catheter tube 124 as it is inserted into an insertion site formed by a percutaneous puncture and advanced through the patient's vasculature.

[0034] Each of the first section 130, second section 132, and junction 134 of the catheter tube 124 is described in more detail below. Similar to that described above for the RICC 102, the catheter tube 124 may be single-lumen or multi-lumen. Indeed, the catheter tube 124 has one or more catheter tube lumens whose names and numbers correspond to those of the RICC 102. One or more catheter tube lumens extend through the catheter tube 124, as described above for the RICC 102.

[0035] Also, similar to that described above for the RICC 102, the catheter tube 124 includes an introduction opening 122 through the side of the catheter tube 124 at its distal portion, as shown. Again, the introduction opening 122 is solely adapted for inserting the introducer needle 104 through the introduction opening 122 to couple the RICC 102 and the introducer needle 104 within the RICC assembly 100. However, neither the RICC 102 nor the catheter tube 124 need include a dedicated introduction opening. Indeed, rather than including the introduction opening 122, the catheter tube can include n-1 side openings through the side of the catheter tube, according to the number n of lumens of the RICC. Any of the n-1 side openings can function as the introduction opening 122 in embodiments of a RICC that do not have a dedicated introduction opening. Considering a three-lumen RICC, such as the RICC 102 described above, the catheter tube of such a RICC would include two side openings, such as the secondary lumen opening 118 and the tertiary lumen opening 120 described above. In addition to providing different openings for blood aspiration, fluid delivery, etc., such side openings can function as introduction openings 122 for coupling the RICC with the introducer needle 104 within a corresponding RICC assembly.

[0036] The first portion 130 of the catheter tube 124 is at the distal portion of the catheter tube 124. The first portion 130 includes a distal tip 136 having a relatively short taper that continues from the beveled tip 146 of the introducer needle 104 in the RICC assembly 100 to the outer diameter of the remainder of the first portion 130. The tapered portion of the distal tip 136 is configured to immediately dilate tissue around the percutaneous puncture made by the introducer needle 104 to the outer diameter of the remainder of the first portion 130 of the catheter tube 124. The first portion 130 also includes a proximal portion that is disposed within a receptacle 138 of the joint 134 and fixedly bonded thereto (e.g., by solvent bonding, adhesive, welding, etc.).

[0037] The first section 130 of the catheter tube 124 is formed from a first polymeric material having a first durometer. The first polymeric material may be, but is not limited to, polytetrafluoroethylene, polypropylene, or polyurethane. Polyurethane is advantageous in that the first section 130 of the catheter tube 124 is relatively rigid at room temperature but becomes more flexible in vivo at body temperature, reducing irritation to the blood vessel wall and phlebitis.

[0038] The second portion 132 of the catheter tube 124 extends from the proximal portion of the catheter tube 124 to the distal portion of the catheter tube 124 but proximal to the first portion 130 of the catheter tube 124. The second portion 132 includes a distal end that is integral (e.g., RF welded) with the proximal end of the joint 134 and a proximal portion that is disposed within the catheter hub 126 and fixedly bonded (e.g., solvent bonded, welded, adhesively, etc.) thereto.

[0039] The second section 132 of the catheter tube 124 is formed from a second polymeric material having a second durometer that is lower than the first durometer. The second polymeric material may be, but is not limited to, polyvinyl chloride, polyethylene, polyurethane, or silicone. In addition to what was discussed above about polyurethane in the first section 130 of the catheter tube 124, polyurethane is advantageous in that it is less thrombogenic than some other polymers.

[0040] A junction 134 of the catheter tube 124 connects the first and second sections 130, 132 of the catheter tube 124. The junction 134 has a receptacle 138 (see FIG. 10 ) at a distal portion, including the proximal portion, of the first section 130 of the catheter tube 124, into which the proximal portion of the first section 130 is disposed and fixedly connected (e.g., by solvent bonding, welding, adhesive bonding, etc.). The proximal end of the junction 134 is integral (e.g., RF welded) with the distal end of the second section 132 of the catheter tube 124, thereby effectively terminating no lumen of the second section 132 of the catheter tube 124 other than the primary lumen 110 through the junction 134. The junction 134 also includes a tapered portion along its length from the distal end to the proximal end configured to immediately dilate the tissue around the percutaneous puncture to the outer diameter of the second section 132 of the catheter tube 124. The abluminal surface of junction 134 transitions smoothly from the abluminal surface of the proximal portion of first section 130 without an edge 140 that can catch on the skin when RICC 102 is inserted into a patient's insertion site. In addition to the negligible edge 140, edge 140 can include a solvent interdiffusion polymer material between the first polymer material and the polymer material of junction 134, which provides a smooth transition from first section 130 of catheter tube 124 to junction 134.

[0041] The junction 134 of the catheter tube 124 is formed from a second polymeric material or a third polymeric material having a third durometer closer to the second durometer than the first durometer, and the second polymeric material may be, but is not limited to, polyvinyl chloride, polyethylene, polyurethane, or silicone.

[0042] Again, the first portion 130 of the catheter tube 124 is formed from a first polymeric material having a first durometer, the second portion 132 of the catheter tube 124 is formed from a second polymeric material having a second durometer that is lower than the first durometer, and the junction 134 of the catheter tube 124 is formed from either the second polymeric material or a third polymeric material having a third durometer that is closer to the second durometer than the first durometer. Because the second and third durometers are lower than the first durometer, the soft portion of the catheter tube 124, including the second portion of the catheter tube 124 and the junction 134, is softer than the hard portion of the catheter tube 124, including the first portion of the catheter tube 124. In other words, the first durometer is higher than the second and third durometers, and because the first durometer is higher than the second and third durometers, the hard portion of the catheter tube 124, including the first portion of the catheter tube 124, is harder than the soft portion of the catheter tube 124, including the second portion of the catheter tube 124 and the junction 134.

[0043] The first durometer hardness of the first polymeric material, the second durometer hardness of the second polymeric material, and the third durometer hardness of the third polymeric material may be on different scales (e.g., Type A or Type D), and thus the second durometer hardness or the third durometer hardness may not necessarily be numerically less than the first durometer hardness. In other words, a material of the first durometer hardness may not be numerically greater than the second durometer hardness or the third durometer hardness in terms of the different scales. However, because each different scale ranging from 0 to 100 is intended to characterize different materials within a group of materials having similar hardnesses, the hardness of the second or third polymeric material may still be less than the hardness of the first polymeric material, or the hardness of the first polymeric material may still be greater than the hardness of the second or third polymeric material.

[0044] Notwithstanding the above, the first portion 130 of the catheter tube 124, the second portion 132 of the catheter tube 124, and the joint 134 can be formed from the same or different polymeric materials having substantially equal durometer hardness, provided that the column buckling strength of the catheter tube 124 is sufficient to prevent buckling of the catheter tube 124 as it is inserted into an insertion site formed by a percutaneous puncture and advanced through a patient's vasculature.

[0045] A catheter hub 126 is coupled to the proximal portion of the catheter tube 124. The catheter hub 126 includes one or more catheter hub lumens corresponding in number to the one or more catheter tube lumens. The one or more catheter hub lumens extend entirely through the catheter hub 126 from the proximal end to the distal end of the catheter hub 126.

[0046] Each extension leg of the one or more extension legs 128 is coupled at its distal portion to the catheter hub 126. Each of the one or more extension legs 128 includes one or more extension leg lumens, the number of which corresponds to the number of the one or more catheter tube lumens. Each of the one or more extension leg lumens extends entirely through the extension leg from its proximal end to its distal end.

[0047] Each extension leg of the one or more extension legs 128 generally includes a luer connector coupled thereto, via which the extension leg and its extension leg lumen can be connected to another medical device.

[0048] The introducer needle 104 includes a shaft 142 , a needle hub 144 around a proximal portion of the shaft 142 , and a beveled tip 146 at a distal portion of the shaft 142 . When the RICC assembly 100 is in a ready-to-deploy state, the introducer needle 104 or its shaft 142 is positioned within the introducer lumen through either the introducer opening 122 (if present), the secondary lumen opening 118, or the tertiary lumen opening 120 (if the introducer opening 122 is not present), or through the puncture formed by the introducer needle 104 such that the beveled tip 146 of the introducer 104 extends beyond the distal end of the first portion 130 of the catheter tube 124 to form a percutaneous puncture. When the introducer needle 104 or its shaft 142 is positioned within the introducer lumen through the secondary lumen opening 118 or the tertiary lumen opening 120, the introducer needle 104 or its shaft 142 is also positioned through the septum 123 that divides the secondary lumen 112 or the tertiary lumen 114 from the primary lumen 110.

[0049] The access guidewire 106 has a length that allows the access guidewire 106 to be advanced a sufficient distance into the vascular lumen once access to the vascular lumen is established to advance the distal portion of the RICC 102 into the vascular lumen and maintain access.

[0050] The access guidewire 106 is positioned within the needle lumen of the introducer needle 104 when the RICC assembly 100 is in at least the ready-to-deploy state. In fact, the distal end of the access guidewire 106 is proximal to the beveled tip 146 of the introducer needle 104 but distal to the junction 134, thereby allowing the distal end of the access guidewire 106 to be immediately advanced beyond the beveled tip 146 of the introducer needle 104 and into the vessel lumen upon establishing access thereto.

[0051] The access guidewire 106 includes a stop 148 (e.g., a hub, ball, slug, etc.) about its proximal portion, which forms a stop end (e.g., a hub end, a ball end, a slug end, etc.) of the access guidewire 106. The stop end of the access guidewire 106 is larger than the RICC 102 or any openings in its catheter tube 124, thereby providing a distal limit for advancing the access guidewire 106 into the RICC 102.

[0052] The operating guidewire 108 includes an atraumatic tip (e.g., a coiled or partially coiled tip) and a length sufficient to advance the operating guidewire 108 to the lower third of the heart's superior vena cava ("SVC").

[0053] When the RICC assembly 100 is in at least the ready-to-deploy state, the steering guidewire 108 is positioned within the primary lumen 110 of the RICC 102 such that its distal end is proximal to the introducer hole 122 but distal to the catheter hub 126, thereby allowing for rapid advancement of the distal end of the steering guidewire 108 into the vessel lumen upon removal of the introducer needle 104 or its shaft 142 from the introducer lumen. In fact, the steering guidewire 108 cannot be advanced further distally within the introducer lumen, at least in the ready-to-deploy state of the RICC assembly 100, due to the presence of the introducer needle 104 or its shaft 142.

[0054] The steering guidewire 108 includes a stop 150 (e.g., a hub, ball, slug, etc.) about its proximal portion, which forms a stop end (e.g., a hub end, a ball end, a slug end, etc.) of the steering guidewire 108. The stop end of the steering guidewire 108 is larger than the proximal end opening in the luer connector of the extension leg into which the steering guidewire 108 is disposed, thereby providing a distal limit for advancing the steering guidewire 108 into the RICC 102. method Methods of RICC assembly 100 include methods of making RICC assembly 100 and methods of using RICC assembly 100. Figures 7A-7C, 9, and 10 show various steps of a first method of making RICCs 102 of RICC assembly 100, according to some embodiments. Figures 8A-8C, 9, and 10 show various steps of a second method of making RICCs 102 of RICC assembly 100, according to some embodiments. Methods of using RICC assembly 100 will be described after the first and second methods of making RICCs 102 are described.

[0055] The first and second methods for fabricating the RICC 102 are similar in that each method includes a mandrel insertion step, a first catheter tube insertion step, a melting step, a pushing step, a first removal step, and a second removal step. The first and second methods differ primarily with respect to the addition of a supplemental polymer material for the joint 134. Indeed, the first method includes adding the supplemental polymer material as one or more polymer rods 152, while the second method includes adding the supplemental polymer material as a sacrificial polymer tube 154. In other words, the method for fabricating the RICC 102 does not need to include the step of adding a supplemental polymer material according to the first or second method, because at least the extra distal portion of the second portion 132 of the catheter tube 124 can function as the supplemental polymer material when fabricating the RICC assembly 100. This extra distal portion of the second portion 132 when fabricating the RICC assembly 100 is a portion beyond the portion required for the second portion 132 of the catheter tube 124 in the RICC 102. That portion forms the joint 134. The steps for adding the supplemental polymer material according to the first and second methods are described first, followed by steps common to the first and second methods, which are described in order in the following paragraphs.

[0056] Notwithstanding the above, whether practicing either the first or second method of making the RICC 102, each of the first and second methods includes a second catheter tube obtaining step or a second catheter tube forming step, named to correspond to the second portion 132 of the catheter tube 124. The second catheter tube obtaining step or the second catheter tube forming step, respectively, includes obtaining or forming the second portion 132 of the catheter tube 124 from a second polymeric material having a second durometer hardness. The second catheter tube forming step includes forming the second portion 132 of the catheter tube 124 by, for example, extruding the second portion 132, cutting the second portion 132 to an appropriate length, etc. The second portion of the catheter tube may be single-lumen or multi-lumen, having one or more additional lumens relative to the primary lumen 110.

[0057] As shown in FIG. 7A, a first method for fabricating a RICC 102 includes a polymer rod insertion step. The polymer rod insertion step involves inserting one or more polymer rods 152 (e.g., about ½ inch (1.27 cm) or less of each of the one or more polymer rods 152) into one or more additional lumens of the second portion 132 of the catheter tube 124. The one or more polymer rods 152 provide a supplemental polymer material for the joint 134, which can be the second or third polymer material described above. The one or more additional lumens are in addition to the primary lumen 110 in a multi-lumen RICC. Such one or more additional lumens include, for example, a secondary lumen 112 or a tertiary lumen 114. The polymer rod insertion step can be performed before or after the mandrel insertion step, but is most easily performed before the mandrel insertion step because the diameter of each of the one or more additional lumens is smaller than the diameter of the primary lumen 110. In fact, locating the additional lumen or lumens may be more difficult if the stepped mandrel 156 is already positioned within the primary lumen 110 and may block the additional lumen or lumens.

[0058] As shown in FIG. 8A, a second method for fabricating the RICC 102 includes a sacrificial tube placement step. The sacrificial tube placement step involves placing a sacrificial polymer tube 154 (e.g., about ½ inch (1.27 cm) of sacrificial polymer tube 154) onto a mandrel 156. The sacrificial polymer tube 154 provides a supplemental polymer material for the joint 134, which can be the second or third polymer material described above. The sacrificial tube placement step can be performed before or after the mandrel insertion step, but is easiest performed before the mandrel insertion step because the diameter of the body of the mandrel 156 is smaller than the diameter of the stepped portion of the mandrel 156. In fact, given the tighter tolerance between the sacrificial polymer tube 154 and the stepped portion of the mandrel 156, it may be more difficult to place the sacrificial polymer tube 154 directly onto the larger diameter of the stepped portion of the mandrel 156 than onto the smaller diameter of the body of the mandrel 156. The sacrificial polymer tube 154 is placed over the body of the mandrel 156 as shown, but it could also be placed over a stepped portion of the mandrel 156, although direct placement may be more difficult as discussed above.

[0059] Advantageously, the second method of making the RICC 102 is useful for single-lumen RICCs that do not include one or more additional lumens relative to the primary lumen 110. Indeed, if the first method of making the RICC 102 and its polymer rod insertion step were used for a single-lumen RICC, the one or more polymer rods 152 would occlude the only primary lumen 110 with the auxiliary polymer material within the RICC 102.

[0060] Whether the first or second method of making RICC102 is performed, each of the first and second methods includes the mandrel insertion step, the first catheter tube insertion step, the melting step, the pushing step, the first removal step, and the second removal step described above.

[0061] As shown in Figures 7B and 8B, the mandrel insertion step involves inserting a mandrel 156 into the primary lumen 110 of the second section 132 of the catheter tube 158 to form the mandrel-mounted catheter tube 158. The stepped portion of the mandrel 156 is spaced a distance from the distal end of the second section 132 of the catheter tube 124, as shown, but the stepped portion of the mandrel 156 can abut the distal end of the second section 132. In fact, it is preferable to insert the mandrel 156 into the primary lumen 110 of the second section 132 of the catheter tube 124 so that the stepped portion of the mandrel 156 is as close as possible to the distal end of the second section 132. As shown in Figure 7B, the mandrel-mounted catheter tube 158 further includes one or more polymer rods 152 disposed in one or more additional lumens. As shown in Figure 8B, the mandrel-mounted catheter tube 158 further includes a sacrificial polymer tube 154 disposed over the mandrel 156.

[0062] As shown in FIGS. 7C and 8C, the first catheter tube insertion step involves inserting the mandrel-mounted catheter tube 158 into the cavity of the RF welding die 160 so that the distal end of the mandrel-mounted catheter tube 158 does not reach the end of the RF welding die 160.

[0063] 7C and 8C, and further shown in FIG. 9, the melting step includes melting the polymer material of the mandrel-mounted catheter tube 158, the supplemental polymer material, or a combination thereof, in the RF welding die 160 by heating the RF welding die 160. The molten polymer material conforms to the cavity of the RF welding die 160 during the melting step to form the welded joint 134 to the second portion of the catheter tube 124. The melting step forms the second portion 132 of the catheter tube 124 and a soft portion of the catheter tube 124 that includes the joint 134.

[0064] 9, the pushing step involves forcing the mandrel 156 and the flexible section of the catheter tube attached to the mandrel together into the end of the RF welding die 160 as the excess molten polymer material seeps out through the exit holes 162 at the end of the RF welding die 160. The pushing action in the pushing step cuts off the excess molten polymer material from the distal end of the flexible section of the catheter tube 124.

[0065] The first removal step involves removing the mandrel 156 and the flexible portion of the catheter tube 124 attached to the mandrel 156 together from the RF welding die 160 . The second removal step involves removing the mandrel 156 from both the primary lumen 110 of the second portion of the catheter tube 124 and the receptacle 138 of the junction 134 .

[0066] Whether the RICC 102 is fabricated using the first or second method, each method includes a first catheter tube obtaining step or a first catheter tube extrusion step, which are named to correspond to the first portion 130 of the catheter tube 124. The first catheter tube obtaining step or the first catheter tube forming step, respectively, includes obtaining or forming the first portion 130 of the catheter tube 124 from a first polymeric material having a first durometer hardness. The first catheter tube forming step includes forming the first portion 130 of the catheter tube 124 by, for example, extruding the first portion 130, cutting the first portion 130 to an appropriate length, etc. The first portion 130 corresponds to the rigid portion of the catheter tube 124.

[0067] When the first or second method is performed as a method for producing RICC102, each of the first and second methods may further include an application step, a second catheter tube insertion step, a bonding step, and an opening formation step.

[0068] The coating step includes a solvent coating step of applying a solvent or an adhesive coating step of applying an adhesive to the proximal portion of the rigid section of the catheter tube 124, the receptacle 138 of the junction 134 of the flexible section of the catheter tube 124, or both. The coating step is performed before the second catheter tube insertion step.

[0069] 10 , the second catheter tube insertion step includes inserting the proximal portion of the rigid section of the catheter tube 124 (i.e., the first portion 130 of the catheter tube 124) into the receptacle 138 of the junction 134. In particular, the inner diameter of the first portion 130 of the catheter tube 124 and the inner diameter of the portion of the primary lumen 110 at the junction 134 are matched after the second catheter tube insertion step. This eliminates the problem of the guidewire getting caught between the luminal surface of the first portion 130 of the catheter tube and the junction 134.

[0070] The bonding step includes evaporating the solvent after the second catheter tube insertion step, thereby forming a solvent-bonded joint between the first portion 130 of the catheter tube 124 and the junction 134 with a solvent interdiffusion polymer material of the first polymer material and the polymer material of the junction 134. If an adhesive is used, the bonding step includes drying the adhesive (i.e., evaporating its solvent) after the insertion step, thereby forming an adhesive-bonded joint between the first portion 130 of the catheter tube 124 and the junction 134, optionally also with the solvent interdiffusion polymer material of the first polymer material, the polymer material of the junction 134, and the adhesive. Thus, the bonding step securely bonds the hard and soft portions of the catheter tube 124 together such that, when the RICC 102 is inserted into a patient's insertion site, the abluminal surface of the distal portion of the junction 134 transitions smoothly over the edge 140 onto the abluminal surface of the proximal portion of the first portion 130 without catching on the skin.

[0071] 10 , the opening forming step includes forming one or more openings, such as secondary lumen opening 118 or tertiary lumen opening 120, for each additional lumen of the one or more additional lumens in the distal portion of the catheter tube 124. The opening forming step may include an opening puncturing step, in which the catheter tube 124 is punctured to form one or more openings, or an opening melting step, in which the catheter tube 124 is melted to form one or more openings.

[0072] Considering the above-described method of making the RICC 102, the first portion 130 of the catheter tube 124 is formed from a first polymeric material having a first durometer, the second portion 132 of the catheter tube 124 is formed from a second polymeric material having a second durometer that is lower than the first durometer, and the junction 134 of the catheter tube 124 is formed from the second polymeric material, a supplemental polymeric material, or a combination thereof, where the supplemental polymeric material is a third polymeric material having a third durometer that is closer to the second durometer than the first durometer.

[0073] A method of using the RICC assembly 100 or its RICC 102 includes an insertion site formation step, a RICC insertion step, and a RICC advancement step. The insertion site creation step includes creating an insertion site for accessing the patient's vascular system with the introducer needle 104 positioned within the primary lumen 110 of the RICC 102. The insertion site may be a subclavian vein, such as the right or left subclavian vein, an internal jugular vein, such as the right or left internal jugular vein, or a femoral vein.

[0074] The RICC insertion step includes inserting a distal portion of the catheter tube 124 of the RICC 102 past a junction 134 between a first portion 130 of the catheter tube 124 and a second portion 132 of the catheter tube 124 into an insertion site, such that the edge between the first portion 130 and the junction 134 does not catch on the patient's skin during the RICC insertion step. Optionally, the RICC insertion step can include an access guidewire insertion step followed by a needle withdrawal step. The access guidewire insertion step includes inserting an access guidewire 106 through the distal end of the introducer needle 104 into one of the aforementioned veins.

[0075] The method further includes a needle withdrawal step, which includes withdrawing the introducer needle 104 from the primary lumen 110 of the RICC 102 after the insertion site preparation step and inserting at least a portion of the distal portion of the catheter tube 124 into the insertion site.

[0076] The RICC advancement step includes advancing the distal portion of the catheter tube 124 through the patient's vasculature without using the Seldinger technique. For example, if the insertion site is in the right subclavian vein or right internal jugular vein, the RICC advancement step may include advancing the distal portion of the catheter tube 124 through the right subclavian vein, right internal jugular vein, and right brachiocephalic vein into the superior vena cava. Other insertion sites, such as the left subclavian vein or left internal jugular vein, require advancing the distal portion of the catheter tube 124 through the corresponding vasculature. Optionally, the RICC advancement step is preceded by a steering guidewire insertion step in which a steering guidewire 108 is inserted through the distal end of the RICC 102 to the target location (e.g., the superior vena cava).

[0077] 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 concepts 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 can deviate from the specific embodiments disclosed herein without departing from the scope of the concepts provided herein.

Claims

1. A catheter, a first section of the catheter tube formed from a first polymeric material having a first durometer, the first section being located in a distal portion of the catheter tube; a second section of the catheter tube formed from a second polymeric material having a second durometer lower than the first durometer, the second section being located in a distal portion of the catheter tube proximal to the first section; a tapered junction of the catheter tube formed from a second polymeric material, a third polymeric material having a third durometer closer to the second durometer than the first durometer, or a combination thereof; the junction terminates such that no lumen other than the primary lumen of the second portion of the catheter tube passes through the junction; A catheter having a first portion of the catheter tube disposed within the receptacle of the tapered junction and having a proximal portion fixedly coupled thereto, whereby the abluminal surface of the distal portion of the tapered junction transitions smoothly onto the abluminal surface of the proximal portion of the first portion with an edge configured to avoid catching on the skin when the catheter is inserted into an insertion site of a patient.

2. The catheter of claim 1 , wherein the edge comprises a solvent interdiffusion polymer material of a first polymer material and a polymer material of the junction.

3. The catheter of claim 1 or 2, wherein the first polymeric material is polytetrafluoroethylene, polypropylene, or polyurethane.

4. The catheter of any one of claims 1 to 3, wherein the second polymeric material is polyvinyl chloride, polyethylene, polyurethane, or silicone.

5. The catheter according to any one of claims 1 to 4, wherein the catheter is a three-lumen catheter having a primary lumen having a primary lumen opening at the distal end of a first portion of the catheter tube, a secondary lumen having a secondary lumen opening on a side surface of a second portion of the catheter tube, and a tertiary lumen having a tertiary lumen opening on a side surface of the second portion proximal to the secondary lumen opening.

6. 6. The catheter of claim 5, wherein the junction comprises a third polymeric material integral to the second portion of the catheter tube, and wherein only the primary lumen extends from the second portion through the junction into the first portion.

7. 7. The catheter of claim 1, wherein the catheter has sufficient column buckling strength to prevent buckling of the catheter tube when inserted into an insertion site and advanced through a patient's vasculature.

8. 1. A method of making a catheter, comprising: inserting a stepped mandrel into the primary lumen of the second section of the catheter tube to form a mandrel-mounted catheter tube; inserting a mandrel-mounted catheter tube into a cavity of a radio frequency ("RF") welding die such that a distal end of the mandrel-mounted catheter tube does not reach the end of the RF welding die; melting the polymeric material of the mandrel-mounted catheter tube, the supplemental polymeric material, or a combination thereof, in an RF welding die by heating the RF welding die, wherein the molten polymeric material conforms to a cavity of the RF welding die during melting to form a tapered junction welded to the second portion of the catheter tube, thereby forming a soft portion of the catheter tube including the second portion of the catheter tube and the junction, and terminating no lumens other than the primary lumen of the second portion of the catheter tube through the junction; forcing the mandrel and the flexible portion of the catheter tube attached to the mandrel together into the end of the RF welding die when excess molten polymer material seeps out of an exit hole at the end of the RF welding die, whereby the mandrel and the flexible portion of the catheter tube attached to the mandrel are forced together into the end of the RF welding die, thereby cutting off excess molten polymer material from the distal end of the flexible portion of the catheter tube; removing the mandrel and the flexible portion of the catheter tube attached to the mandrel together from the RF welding die; removing the mandrel from both the primary lumen of the second section of the catheter tube and the receptacle at the junction; inserting a proximal portion of a rigid portion of a catheter tube into a receptacle of the junction; and joining the hard and soft sections of the catheter tube such that the abluminal surface of the distal portion of the junction transitions smoothly onto the abluminal surface of the proximal portion of the first section, with edges configured to not snag on the skin when the catheter is inserted into the insertion site of a patient.

9. 9. The method of claim 8, further comprising applying a solvent to the proximal portion of the rigid section of the catheter tube, the receptacle of the junction, or both, before inserting the proximal portion of the rigid section of the catheter tube into the receptacle of the junction.

10. 10. The method of claim 8 or 9, further comprising the step of obtaining or extruding a first portion of the catheter tube, the first portion corresponding to the rigid portion of the catheter tube.

11. 11. The method of claim 10, wherein a first section of the catheter tubing is formed from a first polymeric material having a first durometer, a second section of the catheter tubing is formed from a second polymeric material having a second durometer that is lower than the first durometer, and the junction of the catheter tubing is formed from the second polymeric material, a supplemental polymeric material, or a combination thereof, wherein the supplemental polymeric material is a third polymeric material having a third durometer that is closer to the second durometer than the first durometer.

12. 12. The method according to claim 8, further comprising the step of obtaining or extruding a second portion of the catheter tube, wherein the second portion of the catheter tube is multi-lumen, the lumen including a secondary lumen other than the primary lumen and a tertiary lumen.

13. 13. The method of claim 12, further comprising inserting a polymer rod into a lumen other than the primary lumen of the second section of the catheter tube prior to melting the polymer material in the RF welding die, the polymer rod providing a supplemental polymer material.

14. 14. The method of any one of claims 8 to 13, further comprising the step of placing a sacrificial polymer tube over the stepped mandrel before or after forming the mandrel-mounted catheter tube, the sacrificial polymer tube providing the supplemental polymer material.

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