CATHETER ASSEMBLY AND RELATED METHODS

A catheter assembly may include a catheter hub, which may include a distal end, a proximal end, and a catheter hub lumen extending through the distal end of the catheter hub and the proximal end of the catheter hub. The catheter assembly may include a catheter extending from the distal end of the catheter hub. The catheter may include a catheter tube, which may include a distal end, a proximal end, and a catheter tube lumen extending through the distal end of the catheter tube and the proximal end of the catheter tube. The catheter may also include a fluid-permeable section extending from the distal end of the catheter tube. The fluid-permeable section may include a coil or a lattice. The catheter assembly may include an introducer needle extending through the catheter tube and the fluid-permeable section.

BACKGROUND

A common type of catheter assembly includes a peripheral intravenous catheter (“PIVC”) that is over-the-needle. As its name implies, the PIVC that is over-the-needle may be mounted over an introducer needle having a sharp distal tip. The catheter assembly may include a catheter hub, the PIVC extending distally from the catheter hub, and the introducer needle extending through the PIVC. The PIVC and the 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 facing up away from skin of the patient immediately prior to insertion into the skin. The PIVC and the introducer needle are generally inserted at a shallow angle through the skin into vasculature of the patient.

In order to verify proper placement of the introducer needle and/or the PIVC in the blood vessel, a clinician may confirm that there is flashback of blood in a flashback chamber of the catheter assembly. Once placement of the introducer needle has been confirmed, the clinician may remove the introducer needle, leaving the PIVC in place for future blood withdrawal or fluid infusion.

PIVC's often only remain open to flow for a few days and may require removal due to failure prior to their clinical need being fulfilled. In further detail, when the PIVC is inserted into a vein of a patient, it often obstructs blood flow through the vein and creates stasis, which overtime can lead to platelet and fibrin deposition and thrombosis at the distal tip of the PIVC. Also, overtime infusion into the vein via the PIVC contributes to excessive Wall Shear Stress (“WSS”), which causes venous wall damage, leading to phlebitis and thrombosis. As a result of the PIVC's obstruction of flow through the vein and/or infusion, the PIVC may need to be removed prior to completion of infusion and/or blood draw.

SUMMARY

The present disclosure relates generally to vascular access devices and related methods. More particularly, the present disclosure relates to a catheter assembly and related methods. In some embodiments, a catheter assembly may include a catheter hub, which may include a distal end, a proximal end, and a catheter hub lumen extending through the distal end of the catheter hub and the proximal end of the catheter hub. In some embodiments, the catheter assembly may include a catheter extending from the distal end of the catheter hub. In some embodiments, the catheter may include a catheter tube, which may include a distal end, a proximal end, and a catheter tube lumen extending through the distal end of the catheter tube and the proximal end of the catheter tube.

In some embodiments, the catheter may also include a fluid-permeable section extending from the distal end of the catheter tube. In some embodiments, the fluid-permeable section may include a coil or a mesh. In some embodiments, the catheter assembly may include an introducer needle extending through the catheter tube and the fluid permeable section.

In some embodiments, the catheter tube may be over-molded with the coil or the mesh. In some embodiments, the fluid-permeable section may be constructed of a different material than the catheter tube. In some embodiments, the fluid-permeable section may be constructed of a polymer material or metal. In some embodiments, the coil or the mesh may extend along an entire length of the catheter tube. In some embodiments, the coil or the mesh may extend along a partial length of the catheter tube such that a proximal end of the coil or the mesh is spaced apart from a proximal end of the catheter tube.

In some embodiments, the fluid-permeable section may be formed of a same material as the catheter tube. In some embodiments, the distal end of the catheter tube may include a bevel. In some embodiments, a distal end of the introducer needle may include another bevel. In some embodiments, the bevel of the catheter tube may face in an opposite direction as the other bevel of the introducer needle.

In some embodiments, the fluid-permeable section may include one or more clip features and an outer surface of the introducer needle may include one or more corresponding clip features. In some embodiments, the one or more clip features and the one or more corresponding clip features contact each other. In some embodiments, the one or more clip features and the one or more corresponding clip features may be configured to prevent a distal end of the fluid-permeable section from moving proximal to the one or more corresponding clip features. In some embodiments, each of the one or more clip features may include a groove. In some embodiments, each of the one or more clip features may include a protrusion. In some embodiments, the distal end of the fluid-permeable section may include an annular ring. In some embodiments, the annular ring may include the one or more clip features.

In some embodiments, the catheter tube may include multiple slits forming multiple semi-annular sections. In some embodiments, in response to bending of the catheter tube, at least some of the multiple semi-annular sections may be configured to separate to create a fluid pathway from an exterior of the catheter tube to the catheter tube lumen. In some embodiments, the multiple semi-annular sections may be configured to contact each other when the catheter is straight or not subjected to any external load forces. In some embodiments, the introducer needle may extend through the catheter tube and may include a bevel. In some embodiments, each of the multiple slits may extend partially through the catheter tube to maintain a continuous surface aligned with the bevel of the introducer needle. In some embodiments, the multiple semi-annular sections may be a same size.

It is to be understood that both the foregoing general description and the following detailed description are examples and explanatory and are not restrictive of the invention, as claimed. It should be understood that the various embodiments are not limited to the arrangements and instrumentality illustrated in the drawings. It should also be understood that the embodiments may be combined, or that other embodiments may be utilized and that structural changes, unless so claimed, may be made without departing from the scope of the various embodiments of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense.

DESCRIPTION OF EMBODIMENTS

Referring now toFIG.1-2C, in some embodiments, a catheter assembly10may include a catheter hub12, which may include a distal end14, a proximal end16, and a catheter hub lumen18extending through the distal end14of the catheter hub12and the proximal end16of the catheter hub12. In some embodiments, the catheter assembly10may include a catheter20extending from the distal end14of the catheter hub12. In some embodiments, the catheter20may include a peripheral intravenous catheter (PIVC), a midline catheter, or a peripherally-inserted central catheter. In some embodiments, the catheter20may include a catheter tube22, which may include a distal end24, a proximal end26, and a catheter tube lumen28extending through the distal end24of the catheter tube22and the proximal end26of the catheter tube22.

In some embodiments, the catheter20may also include a fluid-permeable section30extending from the distal end24of the catheter tube22. A traditional catheter tube without the fluid-permeable section30causes blood to flow around the traditional catheter tube within a vein of a patient, restricting blood flow within the vein and increasing a likelihood of platelet and fibrin deposition and thrombosis at a tip of the traditional catheter. In some embodiments, in contrast to the traditional catheter tube, when the catheter assembly10is inserted into the vein of the patient for fluid delivery or blood withdrawal, the distal end24of the catheter tube22may be positioned just inside or just outside the vein, and the fluid-permeable section30within the vein may facilitate fluid flow within the vein. Thus, in some embodiments, the fluid-permeable section30may lower blood flow restriction compared to the traditional catheter, reducing platelet and fibrin deposition on the catheter20. The fluid-permeable section30may thereby lengthen a dwell time of the catheter20, increasing a period of time that the catheter20is functional.

In some embodiments, the fluid-permeable section30further allows a clinician to use a larger catheter tube without negatively impacting blood flow restriction through the vein. Moreover, the fluid-permeable section30may maintain structural integrity of the vein, providing a stent-like function and holding the vein open and prolonging an open flow path for blood flow. In some embodiments, the fluid-permeable section30may thus facilitate blood flow from the vein through the fluid-permeable section30and into the catheter tube22and the catheter assembly10.

In some embodiments, the fluid-permeable section30may include a mesh. As used in the present disclosure, the term “mesh” is intended to include any element having an openwork fabric or structure, and may include, but is not limited to, an interconnected network of wire-like segments, a sheet of material having numerous apertures and/or portions removed, or the like. In some embodiments, the mesh may be constructed of metal, a polymer material, or another suitable material such that the mesh is configured to bend or flex when inserted into the vein. In some embodiments, the metal may include stainless steel or another suitable metal. In some embodiments, the polymer may include polyurethane or another suitable polymer. In some embodiments, the mesh may include a lattice, where a geometric space, such as a square or a diamond, is repeated in the circumferential and axial directions of the mesh. In some embodiments, the mesh may be cylindrical and configured to fit within the vein of the patient, with a multiplicity of openings to facilitate fluid flow therethrough. In some embodiments, the fluid-permeable section30may include a coil or another suitable shape configured to facilitate fluid flow therethrough at least when the fluid-permeable section30is in a bent position.

As illustrated inFIG.2A, an introducer needle32may extend from a needle hub33. In some embodiments, the needle hub33may include a flashback chamber and/or a needle safety device. As illustrated inFIG.1, in some embodiments, the introducer needle32may extend through the catheter hub12and the catheter20when the catheter assembly10is in an insertion configuration ready for insertion into the patient. In some embodiments, the introducer needle32may include a sharp distal tip configured to pierce skin and the vein of the patient. In some embodiments, after the introducer needle32is used to place the catheter tube22and/or the fluid-permeable section30within the vein, the catheter20may be advanced distally further into the vein, and the introducer needle32may then be removed from the catheter20and the catheter hub12. In some embodiments, the catheter20may be advanced distally until the catheter hub12contacts or buts up against the skin of the patient.

In some embodiments, the distal end24of the catheter tube22may include a bevel36. In some embodiments, the sharp distal tip of the introducer needle32may include another bevel38. In some embodiments, the bevel36of the catheter tube22may face in an opposite direction as the other bevel38of the introducer needle32. Thus, in some embodiments, the bevel36of the catheter tube22may be oriented generally parallel to the vein, which may facilitate blood flow through the catheter tube22.

In some embodiments, the catheter tube22may be shorter than the traditional catheter tube and may thus cause less blood flow restriction in the vein. In further detail, in some embodiments, after the introducer needle32has been removed and the catheter20is placed in a fluid delivery or blood withdrawal configuration with the catheter hub12contacting or butting up against the skin of the patient, the catheter tube22may be disposed just outside of the vein or just inside the vein. In some embodiments, because the catheter tube22is disposed just outside or just inside the vein, blood flow may be less restricted within the vein compared to the traditional catheter and the catheter20may be used for a longer period of time without failure. In some embodiments, the catheter tube22may be long enough such that it forms a seal with an incision hole extending through the skin of the patient when the catheter20is in the fluid delivery or blood withdrawal configuration with the catheter hub12contacting or butting up against the skin of the patient. In these and other embodiments, the catheter tube22may extend through the skin at an insertion angle between 10° and 30° when in the fluid delivery or blood withdrawal configuration, ready for infusion or blood collection.

As illustrated inFIGS.2B-2C, in some embodiments, the catheter tube22may be closed except for a distal opening35in the distal end24and a proximal opening34in the proximal end26, which may each be aligned with a longitudinal axis of the catheter tube22. In further detail, the catheter tube22may include an annular closed wall, the distal opening35, and the proximal opening34. Thus, there may be little or no leakage of fluid from the catheter tube22proximal to the distal opening35.FIGS.2B-2Cillustrate the catheter20without the mesh or the coil for illustrative purposes.

Referring now toFIGS.3A-3B, in some embodiments, the fluid-permeable section30may be constructed of a different material than the catheter tube22. In some embodiments, the fluid-permeable section30may be constructed of one or more of a metal, a polymer, or another suitable material configured to bend or flex when inserted into the vein. In some embodiments, the metal may include stainless steel or another suitable metal. In some embodiments, the polymer may include polyurethane or another suitable polymer. In some embodiments, the fluid-permeable section30may be constructed of a more flexible material than the catheter tube22since the fluid-permeable section30may bend within the vein when the catheter assembly10is in the fluid delivery or blood withdrawal configuration. In some embodiments, the catheter tube22may be constructed of one or more of polyethylene, silastic, plastic, a polymer, or another suitable material.

In some embodiments, the catheter tube22may be over-molded with the mesh or the coil. In some embodiments, over-molding of the catheter tube22and the mesh or the coil may increase flexibility at an exit of the mesh from the catheter tube22, provide resistance to impact, and provide strain relief. As illustrated inFIG.3A, in some embodiments, the mesh may extend along an entire length of the catheter tube22, which may enhance benefits of the over-molding. In other embodiments, the mesh may extend along a partial length of the catheter tube22such that a proximal end of the mesh is spaced apart from a proximal end26of the catheter tube22.

Referring now toFIG.3C, in some embodiments, the fluid-permeable section30, such as the mesh or the coil, may be formed of a same material as the catheter tube22. In these embodiments, the fluid-permeable section30and the catheter tube22may be monolithically formed as a single unit. In further detail, a tube longer than the catheter tube22may be monolithically formed as a single unit, and cuts may be made in the tube to remove portions of the tube and form the fluid-permeable section30. In some embodiments, the cuts may be made with a laser or another suitable device. In some embodiments, the fluid-permeable section30and the catheter tube22may be monolithically formed as a single unit via injection molding.

Referring now toFIG.3D, in some embodiments, the fluid-permeable section30may include the coil, which may be closed. In further detail, in some embodiments, there may not be significant gaps between individual loops of the coil or the individual loops may contact each other when the fluid-permeable section30is straight or not subjected to any external load forces. In these embodiments, the coil may be similar to a fully compressed tension spring. However, in some embodiments, when the coil is bent or curved, such as when a proximal portion of the coil is disposed at the insertion angle and a distal portion of the coil is disposed at a vein direction angle within the vein, some of the coils may open or expand. In some embodiments, opening or expanding of the coils may increase blood flow from the vein into the coil and into the catheter assembly10.

Referring now toFIG.3E, the fluid-permeable section30may include the coil, which may be open. In further detail, in some embodiments, there may gaps between the individual loops or the individual loops may not contact each other when the fluid-permeable section30is straight or not subjected to any external load forces. In some embodiments, the coil that is open may lower blood flow restriction within the vein compared to the traditional catheter, prolonging a life of the catheter20.

Referring now toFIGS.3D-3E, in some embodiments, the coil may be over-molded with the catheter tube22. In some embodiments, the coil may extend along an entire length of the catheter tube22, which may increase flexibility at an exit of the coil from the catheter tube22, provide resistance to impact, and provide strain relief In other embodiments, the coil may extend along a partial length of the catheter tube22such that a proximal end of the coil is spaced apart from a proximal end26of the catheter tube22.

Referring now toFIGS.4A-4B, in some embodiments, the fluid-permeable section30, such as the mesh or the coil, may include one or more clip features40and an outer surface of the introducer needle32may include one or more corresponding clip features42. In some embodiments, the one or more clip features40and the one or more corresponding clip features42may be coupled together, contacting each other. In some embodiments, the one or more clip features40and the one or more corresponding clip features42may be configured to prevent a distal end44of the fluid-permeable section30from moving proximal to the one or more corresponding clip features42. For example, when the introducer needle32and the fluid-permeable section30are pushed through the skin and/or the vein, coupling between the one or more clip features40and the one or more corresponding clip features42may prevent the fluid-permeable section30from getting caught or bunched.

In further detail, in some embodiments, each of the one or more clip features40may include a groove, as illustrated, for example, inFIG.4B. In some embodiments, each of the one or more corresponding clip features42may include a protrusion, as illustrated, for example, inFIG.4B. In some embodiments, the protrusion may include a distal stop surface that contacts the one or more clip features40and to which force is applied by the one or more clip features40during insertion of the catheter20and the introducer needle32into the patient.

In some embodiments, the one or more clip features40and the one or more corresponding clip features42may be configured to allow easy proximal retraction of the introducer needle32within respect to the fluid-permeable section30and the catheter20. In some embodiments, an outer diameter of the introducer needle32at the one or more corresponding clip features42may be less than an inner diameter of the fluid-permeable section30to facilitate easy proximal retraction of the introducer needle32after the catheter20is inserted within the vein.

In some embodiments, the distal end44of the fluid-permeable section30may include an annular ring46, which may facilitate easy insertion of the fluid-permeable section30into the patient. In some embodiments, the annular ring46may include the one or more clip features40.

Referring now toFIG.5A, a side view of the catheter assembly10inserted into vasculature of the patient and in a fluid delivery or blood withdrawal configuration is illustrated, according to some embodiments. Referring now toFIG.5B, the catheter assembly10is illustrated being inserted into the patient with the introducer needle32, according to some embodiments. Referring now toFIG.5C, the catheter assembly10is illustrated after some distal advancement of the catheter hub12with respect to the introducer needle32, according to some embodiments.FIG.5Dis an enlarged view of a portion of the catheter assembly10ofFIG.5A, according to some embodiments.

Referring now toFIGS.6A-6B, in some embodiments, the catheter tube22may include multiple slits50forming multiple semi-annular sections52. In some embodiments, in response to bending of the catheter tube22, at least some of the multiple semi-annular sections52may be configured to separate to create a fluid pathway from an exterior of the catheter tube22to the catheter tube lumen28. In some embodiments, the multiple semi-annular sections52may be configured to contact each other when the catheter tube22is straight or not subjected to any external load forces. In some embodiments, a particular semi-annular section52in between two other particular semi-annular sections52may contact an entirety of the two other particular semi-annular sections52when the catheter tube22is straight or not subjected to any external load forces, such that little to no fluid passes between the particular semi-annular section52and the two other particular semi-annular sections52. In some embodiments, the introducer needle32may extend through the catheter tube22and may include the other bevel38(see, for example,FIG.1). In some embodiments, each of the multiple slits may extend partially through the catheter tube22to maintain a continuous surface54aligned with the other bevel38of the introducer needle32. In some embodiments, the multiple semi-annular sections52may be a same size as each other, which may facilitate low or no fluid flow into the catheter tube22when the catheter tube22is straight or not subjected to any external load forces.