Peritoneal dialysis catheter having an expandable structure

Abstract

A peritoneal dialysis catheter is disclosed that includes a distal region including a perforated portion and one or more expandable members configured to float the catheter in dialysate within a patient's peritoneal cavity, and a method for using the catheter.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims the benefit of priority to U.S. Patent Application No. 63 / 223,452, filed July 19, 2021, U.S. Patent Application No. 63 / 282,558, filed November 23, 2021, and U.S. Patent Application No. 63 / 312,739, filed February 22, 2022, the entire contents of each of which are incorporated herein by reference.

[0002] The present disclosure relates to medical devices for use in peritoneal dialysis and methods of using such devices. [Background technology]

[0003] End stage renal disease (ESRD) is the final stage of chronic kidney disease (CKD) and occurs when the kidneys are unable to support the body's needs. When this happens, dialysis is needed to help remove impurities and waste products from the blood. The most commonly performed types of dialysis are hemodialysis and peritoneal dialysis.

[0004] For hemodialysis patients, the formation of vascular access in the form of an arteriovenous fistula (AVF) or arteriovenous graft (AVG) is important. However, these vascular access points take time (6 weeks to 4 months) to mature. During this time, the patient still needs an outlet to perform dialysis, which is usually achieved by utilizing a central venous catheter (CVC) as the initial dialysis access for hemodialysis. This type of catheter is problematic because of its high infection rate and negatively impacts the patient's quality of life. CVC infections are dangerous, expensive, and can cause complications that can lead to sepsis and death. Catheter-associated bloodstream infections (CRESI) caused by CVCs are also a leading cause of hospital-acquired infections in the United States.

[0005] CVCs are also used in patients with acute kidney injury (AKI) or acute early chronic kidney disease (ACKD), where the drawback of CVCs is a more rapid decline in estimated glomerular filtration rate (eGFR) compared to hemodialysis using AVFs.

[0006] Compared with hemodialysis, peritoneal dialysis can better preserve residual renal function (RRF). Initiating peritoneal dialysis is favorable for allowing the kidneys to heal and restore their function.

[0007] Peritoneal dialysis utilizes a dialysis solution and dialysate that is infused into the patient's peritoneal cavity. The dialysate contacts the patient's peritoneal membrane within the cavity. Waste, toxins, and excess water pass from the patient's bloodstream through the peritoneal membrane and into the dialysate. The movement of waste, toxins, and water from the bloodstream to the dialysate occurs by diffusion and osmosis. The spent dialysate is drained from the patient's peritoneal cavity to remove waste, toxins, and water from the patient and can then be replaced with additional dialysis cycles.

[0008] In the current method of peritoneal dialysis, a peritoneal dialysis catheter (PDC) is used as an alternative to hemodialysis. The peritoneal dialysis catheter is used to transfer fresh dialysate into the peritoneal cavity and remove spent dialysate from the cavity. The PDC is placed in the peritoneal cavity and uses the peritoneum as an exchange medium for waste products. The PDC is inserted into the peritoneal cavity through the skin, subcutaneous fat, rectus muscle, and parietal peritoneum. Dacron cuffs may be placed in contact with the rectus muscle to promote better attachment to the surrounding tissues. A healing period of 2 to 3 weeks is required to prevent inflammation and infection at the exit site and tunnel area. Fluid (dialysate) is introduced into the peritoneal cavity through the PDC and then retained in the cavity by closing the proximal end of the catheter to prevent the outflow of fluid. Body waste products are drawn into the peritoneal cavity through the peritoneum and are absorbed into the dialysate. After some dwell time, the proximal end of the PDC is opened and the fluid is drained from the peritoneal cavity.

[0009] Typically, peritoneal catheters are implanted into the peritoneal cavity and remain implanted for extended periods of time. For example, while the average catheter may remain implanted for approximately 18-24 months, it is not uncommon for catheters to remain in place for more than two years.

[0010] There are many complications associated with PDCs, but slow drainage is particularly uncomfortable. Slow drainage occurs when the dialysate level drops and the intestine covers the small hole at the distal end of the PDC. Typically, 1-3 liters of dialysate are introduced into the patient's abdomen. For correct fluid and electrolyte balance, the patient needs to drain this entire volume. However, drainage can be impeded if there is not enough dialysate fluid to keep the intestine from temporarily blocking the hole in the PDC as the fluid is drained. Current PDCs are constructed of silicone rubber, which sinks into the most dependent portion of the body, increasing the likelihood of the intestine blocking the hole. Summary of the Invention [Problem to be solved by the invention]

[0011] It would be desirable to develop improved peritoneal dialysis catheters to provide more complete fluid drainage. [Means for solving the problem]

[0012] One aspect provides an elongate tubular member comprising a proximal region, a distal region, and a wall defining a first lumen and a second lumen extending from the proximal region to the distal region, wherein a wall portion disposed in the distal region comprises a perforation in fluid communication with the first lumen and an expandable member disposed on the tubular member in fluid communication with the second lumen, wherein the first lumen is a fluid lumen and the second lumen is an inflation lumen.

[0013] In some embodiments, an expandable member may be disposed longitudinally along a portion of the distal region. The expandable member may be sized to completely enclose at least a portion of the elongated tubular member, e.g., the expandable member may be sized to enclose at least a portion of a circumference of at least a portion of the elongated tubular member.

[0014] In some embodiments, the expandable member may be disposed at the distalmost end of the tubular member and the wall portion including the plurality of perforations is disposed proximal to the expandable member, hi other embodiments, the wall portion including the plurality of perforations is disposed along the elongate tubular member distal to the expandable member.

[0015] In some embodiments, the wall containing the plurality of perforations has a curved shape, such as a helical shape.

[0016] The expandable member may comprise a material selected from the group consisting of nylon, polyamide, polyolefin, polyester, polyurethane, fluoropolymer, polyethylene, polytetrafluoroethylene (PTFE), polyethylene terephthalate (PET), polyvinyl chloride, latex, natural rubber, synthetic rubber, elastomer, silicone, and mixtures and copolymers thereof.

[0017] In some embodiments, the elongate tubular member further comprises at least one cuff, such as a first and a second cuff, disposed on the wall of the elongate tubular member in the proximal region.

[0018] In some embodiments, the expandable member comprises a balloon, or the expandable member comprises an elastomeric sheath defining a cavity and an open-cell foam therein.

[0019] In some embodiments, the wall of the elongate tubular member further comprises a radiopaque stripe extending from the proximal region to the distal region.The elongate tubular member may further comprise a retractable sheath.

[0020] In some embodiments, the elongate tubular member may further comprise a fitting mechanism operably engaged to a proximal region of the elongate tubular member, the fitting mechanism capable of controlling fluid flow through the first lumen. The fitting mechanism may comprise a passage in fluid communication with the first lumen and / or a passage in fluid communication with the second lumen.

[0021] In certain embodiments, a device comprises an elongate tubular member, an expandable member, a first cuff and a second cuff, the elongate tubular member comprising a proximal region, a distal region and a wall including a radiopaque stripe extending from the proximal region to the distal region, the wall defining a first lumen and a second lumen extending from the proximal region to the distal region, the first lumen being a fluid lumen and the second lumen being an inflation lumen, and a wall portion disposed at a distal end of the distal region comprising a helix. and includes a plurality of perforations in fluid communication with the first lumen, the expandable member is disposed longitudinally of the tubular member to completely encapsulate at least a portion of the elongated tubular member along a portion of the distal region disposed proximal to the perforations in the wall, the expandable member comprising a sheath defining a cavity comprising open cell foam in fluid communication with a second lumen, and the first cuff and second cuff are disposed in spaced relation on the wall of the elongated tubular member at the proximal region.

[0022] In this embodiment, the elongated tubular member may further comprise a coupling mechanism operably engaged to the proximal end of the elongated tubular member, the coupling mechanism comprising a first passageway in fluid communication with the first lumen, capable of controlling fluid flow through the first lumen, and a second passageway in fluid communication with the second lumen.

[0023] Another aspect provides a kit including the device described above, including embodiments thereof, and a fitting mechanism configured to engage the device, the fitting mechanism being capable of controlling fluid flow through the first lumen when engaged with the device. The fitting mechanism may comprise a passageway configured to be in fluid communication with the first lumen and / or a passageway configured to be in fluid communication with the second lumen.

[0024] In certain embodiments of the kit, the device comprises an elongate tubular member, an expandable member, a first cuff and a second cuff, the elongate tubular member comprising a proximal region, a distal region and a wall including a radiopaque stripe extending from the proximal region to the distal region, the wall defining a first lumen and a second lumen extending from the proximal region to the distal region, the first lumen being a fluid lumen and the second lumen being an inflation lumen, and a wall portion disposed at a distal end of the distal region comprising a helical spiral. a first cuff having a first cuff shape and including a plurality of perforations in fluid communication with the first lumen, the expandable member disposed longitudinally of the tubular member to completely encapsulate at least a portion of the elongated tubular member along a portion of the distal region disposed proximal of the perforated portions of the wall, the expandable member comprising a sheath defining a cavity including an open cell foam in fluid communication with a second lumen, and the first and second cuffs disposed in spaced relation on the wall of the elongated tubular member at the proximal region. The coupling mechanism is configured to operably engage a proximal end of the elongated tubular member, the coupling mechanism comprising a first passageway and a second passageway configured to be in fluid communication with the first lumen, the coupling mechanism being capable of controlling a flow of fluid through the first lumen when the coupling mechanism is engaged to the proximal end, and configured to be in fluid communication with the second lumen when the coupling mechanism is engaged to the proximal end.

[0025] Embodiments of the kit may further include a stylet to guide insertion of the catheter into the subject's peritoneal cavity and / or a cutting tool to create an opening into the peritoneal cavity for inserting the catheter.

[0026] Another aspect provides a method for performing peritoneal dialysis, comprising inserting a distal region of the device described above, including any embodiment, through an opening in the abdominal wall of a subject requiring dialysis; inflating the expandable member through the second lumen; introducing fluid into the abdomen through the first lumen; maintaining the fluid within the abdomen for a sufficient time for waste products to diffuse into the fluid from blood vessels surrounding the abdomen; and removing the fluid from the abdomen through the first lumen.

[0027] Yet another aspect provides a method for treating a subject in need of peritoneal dialysis, comprising inserting a distal region of an apparatus according to any one of claims 1 to 20 through an opening in the abdominal wall of the subject, inflating the expandable member through the second lumen, introducing fluid into the abdomen through the first lumen, maintaining the fluid within the abdomen for a sufficient time to allow waste products to diffuse into the fluid from blood vessels surrounding the abdomen, and removing the fluid from the abdomen through the first lumen.

[0028] In any of these method embodiments, the apparatus may further comprise a retractable sheath, and the method further comprises retracting the retractable sheath prior to expanding the expandable structure.

[0029] In any of these method embodiments, the method may further include contracting the expandable member after the fluid has been removed from the abdomen. [Brief description of the drawings]

[0030] The invention can be more fully understood from the following description taken in conjunction with the drawings, in which: [Figure 1A] FIG. 1A shows a schematic diagram of one embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 1B] FIG. 1B shows a schematic diagram of one embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 2A]FIG. 2A shows a schematic diagram of another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 2B] FIG. 2B shows a schematic diagram of another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 3A] FIG. 3A shows a schematic cross-sectional view of another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 3B] FIG. 3B shows a schematic cross-sectional view of another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 4A] FIG. 4A shows a schematic side view of another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 4B] FIG. 4B shows a schematic side view of another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 5A] FIG. 5A shows a schematic diagram of a curved embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 5B] FIG. 5B shows a schematic diagram of a curved embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 5C] FIG. 5C shows a schematic diagram of a curved embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 6A] FIG. 6A shows a schematic diagram of another curved embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 6B] FIG. 6B shows a schematic diagram of another curved embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 7A] FIG. 7A shows a schematic cross-sectional view of another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 7B] FIG. 7B shows a schematic cross-sectional view of another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 8A]FIG. 8A depicts an alternative embodiment of a catheter with two expandable structures on a distal region of the PDC, in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 8B] FIG. 8B depicts an alternative embodiment of a catheter with two expandable structures on the distal region of the PDC, in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 9A] FIG. 9A illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 9B] FIG. 9B illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 9C] FIG. 9C illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 10A] FIG. 10A illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 10B] FIG. 10B illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 10C] FIG. 10C illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 10D] FIG. 10D illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 10E] FIG. 10E illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 10F] FIG. 10F illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 10G] FIG. 10G illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 10H] FIG. 10H illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 10I] FIG. 10I illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 10J]FIG. 10J illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 10K] FIG. 10K illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 10L] FIG. 10L illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 10M] FIG. 10M illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 10O] FIG. 10O illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 10P] FIG. 10P illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 10Q] FIG. 10Q illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 10R] FIG. 10R illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 11A] FIG. 11A illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 11B] FIG. 11B illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 11C] FIG. 11C illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 11D] FIG. 11D illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 11E] FIG. 11E illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 11F] FIG. 11F illustrates another embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 12A] FIG. 12A illustrates an embodiment of a catheter in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 12B]FIG. 12B illustrates a catheter embodiment in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 12C] FIG. 12C illustrates a catheter embodiment in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 12D] FIG. 12D illustrates a catheter embodiment in accordance with an exemplary embodiment of the disclosed subject matter. [Figure 13] FIG. 13 shows a schematic diagram of a PDC according to an exemplary embodiment of the disclosed subject matter inserted into a patient's peritoneal cavity for peritoneal dialysis. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention belongs. In case of conflict, this document, including definitions, will prevail. Preferred methods and materials are described below, but methods and materials similar or equivalent to those described herein can be used to carry out or test the present invention. The materials, methods, and examples disclosed herein are illustrative only and are not intended to be limiting.

[0032] As used herein, the terms "comprise," "include," "having," "has," "can," "contain," and variations thereof are intended to be open-ended transitional phrases, terms, or words that do not exclude the possibility of additional acts or structures. The present disclosure also contemplates other embodiments that "comprise," "consist essentially of," and "consist of" the embodiments or elements presented herein, whether or not explicitly stated.

[0033] Advantages of indwelling catheter systems include the option of home treatment, lower cost compared to hemodialysis, and clinical efficiency.

[0034] Conventional peritoneal dialysis (PD) catheter products are single lumen catheters to allow consistent bidirectional flow of dialysate to and from the peritoneal cavity. One or more cuffs are bonded onto the catheter tube to allow tissue ingrowth to maintain catheter placement. Catheters may be in a variety of lengths and cuff configurations, including straight, curled, and swan-neck catheter styles. Catheters are made from translucent silicone rubber tubing that includes radiopaque stripes, along with a felt cuff that can be used to provide catheter stabilization through tissue ingrowth. Current challenges to indwelling catheter systems include bowel obstruction, pain, and incomplete drainage.

[0035] Provided herein is a peritoneal dialysis system with a buoyant catheter that facilitates catheter positioning to minimize the possibility of the catheter being blocked by the intestine. The catheter system described herein is adapted for acute and chronic peritoneal dialysis. The peritoneal dialysis catheter may be inserted using open, laparoscopic, or percutaneous surgical techniques.

[0036] As used herein, the terms "proximal" and "distal" are used to describe opposing axial ends of a device, as well as the axial ends of various component features of the device. The term "proximal" is used in its conventional sense to refer to the end of a device (or component of a device) that is closest to a medical professional during use of the device. The term "distal" is used in its conventional sense to refer to the end of a device (or component of a device) that is first inserted into a patient, or the end that is further from a medical professional during use of the device. For illustration, the distal region of a catheter described herein is inserted into the peritoneal cavity of a patient, and fluids are transferred in and out of the peritoneal cavity via the proximal end.

[0037] As used herein, the terms "expandable member" or "expandable structure," used interchangeably herein, refer to a flexible or elastomeric sheath that can be stretched or expanded from a compressed state having a small volume to an expanded state having a larger volume. As a result, the expandable structure in its expanded state is less dense than the structure in its compressed state, allowing the expandable structure to float in a body cavity filled with bodily fluid. In particular, the sheath is fluid-tight and gas-tight to prevent leakage of fluid into or gas from the structure.

[0038] As used herein, the term "balloon" refers to an inflatable member or structure, including an expandable, flexible, or elastomeric bladder or sheath, which in its inflated state defines an interior cavity that can be filled with a gas, such as helium, hydrogen, nitrous oxide, oxygen, or air. Specifically, the interior of the sheath contains no material; the interior of the sheath contains only gas when in its expanded state. In embodiments, the balloon is configured in a flat, pleated, wrinkled, or folded state to first minimize the cavity for insertion into a subject's body cavity, and then inflated using a gas, such as air, introduced through an inflation lumen in the catheter.

[0039] Alternatively, the expandable member may comprise an expandable sheath defining a cavity containing an open cell foam within the cavity. In some embodiments, the open cell foam is held in a compressed state for insertion into a body cavity of a subject and then inflated or expanded after insertion. In some embodiments, the open cell expandable structure may be inflated like a balloon using gas introduced through an inflation lumen. In other embodiments, the open cell structure is compressed by drawing a vacuum through the inflation lumen. When the vacuum is released, air enters the inflation lumen and into the open cell structure, thereby expanding the open cell structure. In other embodiments, the open cell structure may be self-expanding, in which case the open cell foam maintains a compressed form until compression is released. For example, a valve may be opened to allow rapid expansion of the open cell foam, or a vacuum may be created that draws gas from the inflation lumen into the expanding open cells.

[0040] In any of the foregoing embodiments, the catheter may further comprise a retractable non-elastomeric or non-expanding sheath that is radially disposed around the expandable member to prevent expansion of the expandable member until it is desired to expand the expandable member. For example, the non-expanding sheath may be retracted from around the expandable member after insertion into the subject. When the non-expanding sheath is retracted, it allows inflation of the balloon or open-cell foam with gas introduced via the inflation lumen. In self-expanding embodiments, retraction of the non-expanding sheath can function as a "valve" that allows the compressed open-cell foam to expand.

[0041] The expandable structures described herein provide a portion of the catheter at the distal region of the catheter with reduced density, allowing the distal region of the catheter to float near the top of the peritoneal fluid in the peritoneal cavity to facilitate drainage.

[0042] For the purpose of promoting an understanding of the principles and features of the catheter and its method of use, specific language will be used to describe the embodiments shown in the drawings, nevertheless the scope of the device is not limited to the specific language used, and changes and modifications in the illustrated devices, and further applications of the features of the catheters illustrated herein that would normally occur to one of ordinary skill in the art to which the invention pertains, are contemplated.

[0043] While the devices described herein can take many different forms, preferred embodiments are described in this disclosure and illustrated in the accompanying drawings, which illustrate the principles of the disclosed devices and do not limit the broad aspects of the devices and methods for their use to only the illustrated embodiments.

[0044] Aspects of the present disclosure provide a medical device or catheter for performing peritoneal dialysis.

[0045] 1A and 1B, a first embodiment of such a device is shown. The catheter 10 includes a flexible elongated tubular member 11 having a first internal lumen (not shown) extending from a proximal region 12 to a distal region 13. The length and shape of sections 11, 12, and 13 can vary depending on the embodiment of the catheter. For ease of presentation, the length of the elongated tubular member is shown with a break along its length, and the length of the tubular member can be dimensioned to fit within the abdominal cavity of a patient. The wall of the elongated tubular member 11 in the proximal and portions of the distal regions is devoid of openings that provide a fluid pathway between the first lumen and the exterior of the device, except for a perforated segment in the distal region, which will be described further below. The catheter 10 is made of flexible medical grade tubing suitable for implantation within a patient's body. In various embodiments, the wall thickness along at least a portion of the elongate tubular member is between 2 mm and 0.25 mm, or between 2 mm and 0.5 mm, or between 1.5 mm and 0.5 mm, or between 1.0 mm and 0.5 mm, or between 2 mm and 1.0 mm, or between 0.25 mm and 0.5 mm, or between 0.25 mm and 0.4 mm, or between 0.25 mm and 0.3 mm.

[0046] The proximal region 12 of the catheter 10 provides the ability to connect the catheter 10 to a dialysate supply and removal system, such as an automated peritoneal dialysis system (not shown). The proximal region 12 includes an end 14 configured to be attached to the dialysate supply and removal system via a connector fitting and tubing. The lumen can then transfer fluid between the peritoneal cavity and the dialysate supply and removal system. An external tube or lumen (not shown) is disposed outside the patient and connected to the automated peritoneal dialysis system and the proximal region 12 to provide fluid communication therebetween. The catheter 10 may have a generally vertical orientation when implanted in a patient with the distal region 13 disposed upward toward the top region of the peritoneal cavity. The proximal region 12 may be positioned downward toward the bottom of the peritoneal cavity.

[0047] The proximal region 12 may also provide for anchoring of the catheter 10 to the patient by one or more implant cuffs 15, 16 disposed on the wall of the elongated tubular member in the proximal region 12. The catheter 10 is implanted in the patient with cuff 15 positioned just under the patient's skin and cuff 16 implanted in the patient's rectus muscle.

[0048] The cuff can improve sealing of the catheter inlet opening. The cuff can be formed from a material including, for example, polyethylene terephthalate (e.g., DACRON) or another biocompatible polymeric material. The implant cuffs 15, 16 can be polyester felt, or other material that allows for tissue ingrowth into the cuff. Subcutaneous tissue can grow into the implant cuffs 15, 16 to secure the catheter 10 to the patient.

[0049] In other embodiments, the cuff comprises a remodelable material. Such a remodelable material can remodel or promote cell growth and / or promote regrowth and healing of damaged tissue structures. The presence of such a remodelable material can promote cell ingrowth and fixation of the catheter to the rectal sheath. This can help stabilize the catheter and provide improved sealing of the opening. In other embodiments, the remodelable material is present on the surface of the elongate member or is incorporated into the structure of the elongate member.

[0050] The remodelable material may be, for example, extracellular material (ECM), small intestinal submucosa (SIS), remodelable foam or collagen foam, foamed ECM, freeze-dried SIS or vacuum-pressed SIS. A non-limiting example of a suitable remodelable material is SURGISIS™, BIODESIGN™, available from Cook Incorporated, Bloomington, Ind. Another suitable remodelable material is the graft prosthesis material described in U.S. Patent No. 6,206,931, which is incorporated herein by reference.

[0051] When the catheter 10 is implanted inside the patient, the portion of the catheter 10 from the proximal end 14 near the cuff 15 is external to the patient and can be considered the external patient portion. The remaining portion of the catheter 10 is implanted inside the patient and can be considered the implantable portion. As shown in Figures 1A and 1B, the implantable portion can have a generally non-linear shape, although the portion of the implantable portion can be substantially linear. Because the tube is flexible, it can adopt a configuration that fits within the peritoneal cavity.

[0052] In some embodiments, radiopaque stripes may extend along the length of catheter 10. Under an x-ray, the radiopaque stripes indicate the location of catheter 10 inside the patient.

[0053] The distal region 13 includes a plurality of perforations or holes 17 in fluid communication with the first lumen and the expandable member or structure. The number and size of the perforations 17 are not limited, but may be configured to allow the passage of extracellular fluid into the first lumen, but not cellular material.

[0054] In some embodiments, the expandable member comprises an expandable structure, such as a balloon. Thus, the device also includes at least one inflation tube in a second lumen (not shown) to provide inflation of the expandable structure. The inflation tube typically extends from the proximal region 12 of the device to the expandable structure and is in fluid contact with the interior of the expandable structure. For example, the elongate tubular member 11 may have at least two lumens, a larger first lumen for passage of dialysis fluid and a smaller second lumen to provide inflation of the expandable structure. As discussed above, the expandable structure may include a balloon or an open-cell foam structure.

[0055] In the embodiment shown in Figures IA and IB, a plurality of perforations is disposed at the distal end of distal region 13, and an expandable member is disposed proximal to the plurality of perforations.

[0056] In FIG. 1A, the expandable structure is shown in a contracted or compressed state 18a and is positioned proximal to the multiple perforations 17. A retractable sheath (not shown) may be used around the expandable structure 18a to protect the contracted expandable structure during insertion of the catheter into the patient's abdomen. FIG. 1B shows the expandable structure in an expanded state 18b. After expansion, the expandable structure acts as a float to keep the distal region 13 of the catheter 10 near the upper level of fluid in the patient's abdomen so that the catheter does not sink and become blocked by the patient's intestines. The expandable structure may also hold a distal portion of the sheath away from the surface of the intestine to further reduce the possibility of the intestine blocking the perforation area.

[0057] In some embodiments, the expandable structure is disposed longitudinally along the length of the distal region 13.

[0058] The expandable structure of the device may be manufactured from any material typically used in the manufacture of expandable structures. For example, the expandable structure may include materials such as nylon, polyamide, polyolefin, polyester, polyurethane, fluoropolymer, polyethylene, polytetrafluoroethylene (PTFE), polyethylene terephthalate (PET), polyvinyl chloride, latex, natural rubber, synthetic rubber, elastomer, silicone, or mixtures and copolymers of these materials, or two or more of these materials.

[0059] Foams are materials formed by trapping gas within a liquid or solid. During the expansion and curing of open-cell foams, the air cells used in their production are released into the atmosphere rather than being fixed in place as in closed-cell foams. Open-cell foams are foams in which the compartments within the material have been broken down, allowing air to occupy the spaces within. Open-cell foams contain pores that are connected to each other and form a relatively soft interconnected network with a sponge-like appearance. Open-cell foams are typically lighter and less dense compared to closed-cell foams, and more expansive than closed-cell foams. There is an array of open-cell foam materials, but generally they are made from polyurethane, reticulated polyurethane, PVC / nitrile, ethylene propylene diene monomer (EPDM) rubber, etc. A notable material is medical grade silicone open-cell foam.

[0060] As shown in FIGS. 1A and 1B, the distal region 13 of the catheter may be curved, such as in a helix or "pigtail" shape, to provide stabilization of the catheter. In such curved embodiments, the curve may be the result of a shape memory configured into the catheter during manufacture. During insertion, the curved portion may be "straightened" by passing the catheter through a straight stylet. After insertion, when the straight stylet is removed or retracted from the catheter 10, the distal region 13 may resume its curved shape. Alternatively, a retractable sheath may hold the catheter in a straight configuration for insertion.

[0061] 2A-6B show aspects of other embodiments of the catheter 10 described herein. In these embodiments, the elongate tubular member 11 and proximal region 12 are substantially similar to those shown in Figures 1A and 1B, and therefore, for ease of presentation, are not shown in Figures 2A-6B.

[0062] 2A and 2B, distal region 23 includes an expandable structure disposed at a distal end of distal region 23 and a plurality of perforations 27 disposed proximally of said expandable structure adjacent to non-perforated regions of elongate tubular member 11. In FIG. 2A, expandable structure 28a is in a contracted or compressed state. In FIG. 2A, expandable structure 28b is in an expanded or expanded state.

[0063] In other embodiments, the expandable structure and the perforations occupy separate sections along substantially the same length of the distal region, with the expandable structure disposed in a first portion of the circumference of the distal region and the multiple perforations disposed in a second portion of the circumference of the distal region. In these embodiments, the expandable structure may be disposed along the entire length of the perforated portion of the distal region of the PDC. Schematic cross-sections of catheter 10 according to these embodiments are shown in Figures 3A and 3B. In Figure 3A, distal region 33 includes a septum 34 that divides tubular member 11 into a first lumen 35 and a second lumen 36, each of which extends the length of catheter 10 from proximal region 12 to distal region 33. First lumen 35 is in fluid communication with perforated region 37, which includes multiple perforations, similar to perforations 17 shown in Figure 1A. Second lumen 36 is in fluid communication with the expandable structure, shown in contracted configuration 38a in Figure 3A. Passage of gas through second lumen 36 causes the expandable structure to expand, as shown in expanded state 38b in FIG. 3B.

[0064] 4A and 4B show side views of the distal region 33 shown in Figures 3A and 3B, taken along line A shown in Figure 3A. Although the distal region 33 has a simple "straight" configuration in these figures, it is noted that the catheter is flexible and the straight configuration may actually bend and curve when deployed in a patient. The perforated region 37 occupies a first circumferential portion of the distal region 33, and the expandable structure occupies a second circumferential portion of the distal region 33 in the contracted configuration 38a in Figure 4A and the expanded configuration 38b in Figure 4B.

[0065] 5A-5C show schematic diagrams of curved embodiments of the catheter as viewed along line A shown in FIG. 3A. In FIG. 5A, the distal region 33 has a curved configuration in which the perforated portion 37 of the distal region 33 occupies the inner (smaller) radius of the curved configuration and the contracted expandable structure 38a occupies the outer (larger) radius of the curved configuration. FIG. 5B shows the same catheter with the expandable structure in its expanded state 38b. FIG. 5C shows the helical shape of the distal region 33, with the expandable structure shown in the expanded state. As mentioned above, the curvature shown in FIGS. 5A-5C is not limited and the curvature is not fixed as the catheter comprises a flexible material and can be straightened for insertion into a patient and then reformed after insertion.

[0066] In other embodiments not shown, the expandable structure can occupy the inner radius of the curved distal region.

[0067] Figures 6A and 6B show another embodiment of a curved distal region. In this embodiment, the distal region is viewed along line B in Figure 3A and includes a cross section according to the cross section shown in Figures 3A and 3B. In this embodiment, the expandable structure occupies the "top" of the catheter relative to the axis of the catheter's curve, and the perforated region occupies the "bottom" of the catheter relative to the axis of the catheter's curve. In Figure 6A, the catheter is viewed from the bottom along line B, which is parallel to the axis of curvature. The expandable structure in Figure 6A is in a contracted state and is therefore not visible behind the perforated portions 37. In Figure 6B, the expandable structure is in an expanded state 38b and is visible behind the perforated portions 37.

[0068] 7A and 7B show schematic cross-sectional views of another embodiment of a catheter with two expandable structures disposed diametrically opposite on the distal region of the PDC. The catheter comprises a tubular member 70 with two partitions 71 and 72 that divide the tubular member 70 into a larger (first) lumen 73 and two smaller lumens 74 and 75. The lumen 73 is in fluid communication with two diametrically opposite perforated portions 76 and 77 of the tubular member 70. The lumen 73 extends the length of the tubular member and is configured to carry dialysate between the proximal region 12 of the catheter and the distal portion shown. The lumens 64 and 75 also extend the length of the tubular member and are configured to carry inflation gas from the proximal region 12 of the catheter to the expandable structures. In FIG. 7A, the expandable structures are shown in contracted or compressed states 78a and 79a. In FIG. 7B, the expandable structures are shown in inflated or expanded states 78b and 79b.

[0069] Figures 8A and 8B show an alternative embodiment of a catheter with two expandable structures on a distal region of the PDC. In this embodiment shown in Figure 8A, the PDC comprises a distal region 83 having a first expandable structure 86a in a compressed state disposed distally to a perforated region 87 and a second expandable structure 88a in a compressed state disposed proximally to the perforated region 87. Figure 8B shows the same distal region 83 with the expandable structures in expanded states 86b and 88b resulting in a "barbell" configuration.

[0070] Although not limiting, two expandable structures are shown in Figures 7A, 7B, 8A and 8B, in some embodiments, the PDC may comprise multiple expandable structures.

[0071] 9A, 9B, and 9C show aspects of one embodiment of a peritoneal dialysis catheter, the distal end of which is shown extended in a straight line. One embodiment of the catheter 90 includes two main features. First, as shown in detail in FIG. 9B, the catheter 90 includes a dual lumen silicone tube 91 with one lumen 92 for infusion and drainage of dialysate and another lumen 93 for transmitting or carrying vacuum or air to collapse or expand the silicone balloon or sheath with a foam insert. Second, the catheter 90 includes a silicone balloon or sheath 94 with a compressible foam insert (not shown) attached near the distal end of the catheter, which is placed inside the peritoneal cavity after insertion. The foam insert inside the balloon expands with air to provide buoyancy during dialysis and improve drainage of dialysate. The distal end 95 of the catheter includes a laser ablated baffle with perforations in the fluid lumen, including multiple laser ablated holes located along the perforation area of ​​the catheter. The perforations provide fluid communication from the peritoneal cavity to the catheter's fluid lumen 92. Although distal end 95 is shown in an extended, linear configuration, such as for insertion into the subject's peritoneal cavity, distal end 95 can adopt a curved or helical configuration after insertion, as previously described.

[0072] In some embodiments, the distal tip 96 of the catheter is configured to minimize contact between the distal working end of the catheter and the intestinal, bladder or peritoneal surface. As shown in detail in FIG. 9C, the distal tip comprises a crenellated tip 96 having a plurality of alternating longitudinal protrusions or peaks 96a and longitudinal depressions or valleys 96b. In the illustrated embodiment, the tip comprises, but is not limited to, two diametrically spaced protrusions or peaks and two diametrically spaced depressions or valleys.

[0073] 9A, the catheter includes one or more ingrowth cuffs 97 near the proximal end of the catheter. The cuffs provide a substrate for tissue ingrowth and facilitate anchoring the proximal end of the catheter 90 near the peritoneal wall of the subject. The cuffs may be made from polyethylene terephthalate (DACRON) fibers and are disposed around the catheter.

[0074] A silicone balloon or sheath 94 with a compressible foam insert may be placed into the peritoneal cavity through the peelable or retractable sleeve. First, the balloon is folded for insertion into the abdomen. During implantation, the system is kept under vacuum to keep the buoyancy balloon compressed. Exposure to atmosphere through lumen 93 causes the balloon to expand. When the negative pressure is removed, air can enter the foam insert and expand the balloon.

[0075] Another embodiment of a catheter is shown in Figures 10A-10R. Figures 10A and 10B show a catheter 1000 in an assembled and disassembled state, respectively. The catheter 1000 comprises a dual lumen catheter body 1001 having a silicone balloon or sheath 1004 disposed near a distal end 1005. Inside the balloon 1004 is a foam insert 1008. Two ingrowth cuffs 1007 are disposed around the catheter body. Disposed at the proximal end of the catheter is a vacuum adapter 1100 configured to engage the proximal end 1009 of the catheter body 1001 and provide a connection to a fluid handling system for moving dialysate into and out of the peritoneal cavity. Figure 10C shows a non-coiled view of the catheter 1000 with representative dimensions of parts shown. In the illustrated embodiment, the catheter has an uncoiled length of 625 mm, an outer diameter of the catheter of 4.75 mm, and a wall thickness of 1.0 mm. Considering the air lumen, this results in a cross-sectional area of ​​5.4 mm for fluid to pass through. The silicone balloon 1004 has an outer diameter of 12.5 mm in its expanded or uncompressed state. During implantation, the system is kept under vacuum to keep the buoyancy balloon compressed. When a vacuum is applied to the proximal end of the air lumen for insertion into the subject's peritoneal cavity, as shown in FIG. 10D, the outer diameter of the balloon 1004 is compressed to about 8 mm. The distal end 1005 of the catheter is positioned uncoiled for insertion and is held in a removable sleeve. FIG. 10E shows the catheter after it has been placed in the peritoneal cavity. When the negative pressure is removed, the balloon expands and air can enter the foam insert. The distal end 1005 is shown in its coiled (spirally) state.

[0076] FIG. 10F shows the catheter comprises an extrusion with a cross section of the catheter at AA shown in FIG. 10E. The cross section shows a fluid lumen 1002 and a vacuum / air lumen 1003. A radiopaque stripe 1010 co-extruded with the dual lumens is also shown. FIG. 10G shows a cross section of the catheter at BB shown in FIG. 10E with the foam insert 1008 expanded. The foam comprises an open cell foam. A plurality of larger diameter holes disposed around the catheter provide an open space that may collapse when a vacuum is applied through the lumen 1003 or expand when air is applied through the lumen 1003. Although not shown, the lumen 1003 is perforated in the area of ​​the catheter that contacts against the foam insert 1008 to provide fluid (air) communication between the lumen 1003 and the foam 1008.

[0077] In some embodiments, the tip of the catheter is configured to minimize contact between the distal working end of the catheter and the intestinal, bladder, or peritoneal surface. In this embodiment, the tip comprises an end opening and a number of openings disposed around the catheter. As shown in FIG. 10H, the distal tip 1006 comprises, but is not limited to, two elongated openings 1006a disposed diametrically on either side of the tip and an end opening 1006b. The distal tip 1005 includes a number of laser ablated holes 1005a disposed along its length.

[0078] Figure 10I shows a cutaway side view of the catheter 1000 at the balloon portion along line CC shown in Figure 10C. Foam 1008 is disposed around the catheter 1001 and inside the balloon 1004. The balloon 1004 is attached to the outside of the catheter using a solvent bond or adhesive. A V-cut 1012 into the vacuum lumen 1003 provides fluid communication from the lumen 1003 to the foam 1008. Also shown is the distal tip 1006.

[0079] FIG. 10J shows the catheter lumen 1001 without other components of the catheter. The distal end is shown with a helical coil having a length of about 330 mm and an outer diameter of about 50 mm. The distal end includes multiple laser ablated holes spaced about 10 mm apart. FIG. 10K shows a cross-section of the lumen at line EE of FIG. 10J. FIG. 10L shows a side view and a perspective view of the balloon 1004. FIG. 10M shows a side view and a perspective view of the foam insert 1008. The foam 1008 can be assembled from multiple shorter side-by-side segments configured around the catheter. This allows for the preparation of catheters with expandable structures of different lengths. FIG. 10N shows a front view of the balloon 1004 and FIG. 10O shows a front view of the foam insert 1008. FIGs. 10P, 10Q, and 10R show a front view, a side view, and a perspective view, respectively, of the ingrowth cuff 1007.

[0080] 11A-11F show an embodiment of a vacuum adapter 1100 that is engaged with a proximal end of a catheter to provide fluid communication from a subject's peritoneal cavity through the catheter 1000 to other fluid handling structures outside the subject's peritoneum. FIG. 11A shows a side view of the vacuum adapter 1100. The vacuum adapter includes a male luer fitting 1102 on its proximal end 1101 for attachment of a syringe or other fluid handling system. The adapter's central section 1103 includes a vacuum check valve. The adapter's distal end 1104 is configured to engage with the proximal end of the dual lumen catheter 1000. FIG. 11B shows a cross-sectional view of the adapter 1100 along line WW of FIG. 11A. As shown in FIG. 11B, the proximal end 1101 and distal end 1104 engage with one another to define a fluid passageway 1005 that allows dialysate fluid to pass therethrough. They are engaged to provide a vacuum check valve 1103. The diameter of the passageway 1105a at the proximal end 1101 is sized to engage an external tube, which may be configured to lock onto the male luer fitting 1102 with a female luer fitting. The diameter of the passageway 1105b at the distal end 1104 is sized to engage the outer diameter of the catheter 1000. The small passageway 1006 is configured to be inserted into the lumen 1003 of the catheter 1000 to transfer air or vacuum from outside the catheter into the lumen 1003. FIGS. 11C and 11D show perspective views of the vacuum adapter 1100. FIG. 11E shows a view of the proximal end of the adapter 1100. FIG. 11F shows a view of the distal end of the adapter 1100.

[0081] 12A-12D show photographs of embodiments of catheter 1000 and adapter 1100. FIG. 12A shows the proximal end of catheter 1000 and the distal end of vacuum adapter 1100 side-by-side. It can be seen that air passageway 1105b is sized to engage the outer diameter of catheter 1000, thereby allowing fluid communication with fluid lumen 1002. It can also be seen that air passageway 1106 is sized to be inserted into lumen 1003.

[0082] FIG. 12B shows the distal end 1005 of the catheter 1000 and the balloon 1004 with the balloon 1004 in a compressed state. It can be seen that the skin of the balloon 1004 is wrinkled or pleated, indicating that it is not expanded. Also shown is a radiopaque stripe 1010 extending the length of the distal end 1005. FIG. 12C shows the distal end 1005 of the catheter 1000 and the balloon 1004 with the balloon 1004 in an expanded state. It can be seen that the skin of the balloon 1004 is smoother than in FIG. 12B, indicating that a foam insert inside the balloon has expanded and inflated the balloon 1004. FIG. 12D shows the catheter 1000 in a pool of water. It can be seen that the expanded balloon 1004 floats on the surface of the water, while the distal end 1005 and the proximal end 1009 are submerged. This demonstrates that the expandable structure (e.g., balloon 1004) provides sufficient buoyancy to orient the catheter 1000 so that the distal end can be positioned near and above the fluid in the subject's peritoneal cavity.

[0083] The expandable structure can be inflated by a physician after standard laparoscopic, open, or percutaneous implantation of the catheter system. Peritoneal dialysis can be performed by a healthcare provider and / or the patient via standard techniques. Dialysis fluid is infused into the peritoneal cavity by connecting a dialysate bag to the catheter. The device achieves a current standard flow rate of 6 L / hr. This catheter system can be used for APD or CAPD. The balloon remains inflated due to an expanding open / closed cell foam insert (scaffold). In some embodiments, the catheter is made from translucent silicone rubber tubing containing radiopaque stripes with a felt cuff that can be used for stabilization of the catheter by tissue ingrowth.

[0084] Also provided are kits including a catheter as described herein and a transfer fitting or vacuum adapter as described herein, optionally further including a stylet for guiding insertion of the catheter into the peritoneal cavity of a subject, and optionally further including a cutting tool, such as a scalpel, to create an opening into the peritoneal cavity for inserting the catheter. The kit may further include instructions for use of the catheter.

[0085] Another aspect of the present invention provides a method for performing peritoneal dialysis. As generally shown in FIG. 13, the distal end of the catheter device disclosed above is inserted through an opening in the abdominal wall of a patient requiring dialysis. During this stage of the procedure, the expandable member including the expandable structure is typically in a contracted or compressed configuration. For example, the expandable structure may be confined within the lumen of a delivery sheath.

[0086] In use, the distal end of the device is first inserted through an opening in the abdominal wall such that the distal region containing the expandable structure and the multiple perforations are located within the abdominal cavity. The expandable structure is typically in a contracted or compressed state during this stage of the procedure. In some embodiments, the expandable structure is compressed by applying a vacuum through the air lumen. After the elongate member is inserted to the desired length, the expandable structure can be inflated. For example, the expandable structure can be inflated through an inflation tube(s) with a gas such as air or helium.

[0087] Dialysate is delivered from the proximal end 12 of the elongate member 11 to the distal end of the device and then to the peritoneal cavity via the first lumen, which thus provides a leak-tight pathway from the outside to the patient's abdomen.

[0088] In embodiments in which the distal region of the catheter includes a curved portion, the catheter is passed into the abdomen utilizing a straight stylet, and when the stylet is removed, the catheter curves or bends.

[0089] The expandable structure may then be expanded by inflation with gas delivered from a proximal region in the device to the expandable structure via an inflation tube in the second lumen. Gas for inflation of the expandable structure may be provided from an automated peritoneal dialysis system or from another device, usually a syringe, connected to the second lumen at the proximal region of the catheter. In one embodiment, the expandable structure may be expanded after insertion into the abdomen and before introduction of dialysate. Alternatively, the expandable structure may be expanded after introduction of dialysate. The expandable structure may be expanded before or after introduction of dialysate to maximize drainage during the drainage period. Alternatively, the expandable structure may remain expanded for the life of the indwelling PDC (up to several years).

[0090] A volume of dialysate is introduced into the abdomen through the first lumen of the elongate member. Typically the volume of fluid introduced is about 1-3 liters, and the fluid is introduced over a period of about 10-15 minutes. The fluid remains in the peritoneal cavity, and waste products diffuse from the underlying blood vessels across the peritoneum into the fluid in the peritoneal cavity. After a variable period of time depending on the treatment, typically 4-6 hours, the fluid is removed through the lumen of the device while the expandable structure is inflated. This air-filled expandable structure system is positioned adjacent to the perforated portion of the PDC in the distal region to float the PDC on top of the dialysate. This maximizes the contact of the PDC with the dialysate (away from the intestine) as the level drops due to drainage. The expandable structure-PDC described herein floats until the fluid is completely removed.

[0091] This process can be done automatically while the patient sleeps (automated peritoneal dialysis), or by keeping 1-3 liters of fluid in the peritoneal cavity at all times and exchanging the fluid 4-6 times a day (continuous ambulatory peritoneal dialysis).

[0092] Automated peritoneal dialysis is similar to continuous peritoneal dialysis in that the dialysis treatment includes at least one drain, fill, and dwell cycle. However, the dialysis machine automatically performs 1-5 cycles, such as 3-5 cycles of peritoneal dialysis treatment, typically overnight while the patient sleeps. It may be understood that the dwell time is variable depending on the number of cycles envisioned during the dialysis treatment. The dialysis machine is fluidly connected to an implanted catheter. The dialysis machine is also fluidly connected to a source of fresh dialysate, such as a bag of dialysate solution, and to a fluid drain. The dialysis machine pumps spent dialysate from the peritoneal cavity through the catheter and into the drain. The dialysis machine then pumps fresh dialysate from the dialysate source through the catheter and into the patient's peritoneal cavity. The dialysis machine allows the dialysate to dwell in the cavity in order to transfer waste, toxins, and excess water from the patient's bloodstream into the dialysate solution. The dialysis machine is computer controlled so that the dialysis treatment is performed automatically when the patient is connected to the dialysis machine, for example overnight. Multiple drain, fill, and dwell cycles occur during the treatment. Also, at the end of an automated dialysis treatment, a final fill is typically used, allowing the patient to disconnect from the dialysis machine and continue with their daily functions while the dialysate remains in the peritoneal cavity. Automated peritoneal dialysis frees the patient from manually performing the drain, dwell, and fill steps, which can improve the patient's dialysis treatment and quality of life. Further rounds of dialysis treatment using the PDC described herein can be performed over an extended period of time.

[0093] Catheters may be used as a temporary means to provide dialysis to maintain blood homeostasis while waiting for another form of dialysis therapy to begin, to allow the kidneys to recover from trauma, or while waiting for a hemodialysis access point to heal, hi other embodiments, catheters may be used permanently for peritoneal dialysis.

[0094] When the need for peritoneal dialysis ends, such as when an alternative dialysis treatment is initiated or a kidney is transplanted into the subject, the expandable structure can be deflated and the catheter removed from the subject.

[0095] The fluids used typically contain sodium salts, such as sodium chloride, sodium lactate, or sodium bicarbonate, to ensure hyperosmolality, and a high percentage of glucose. The amount of dialysis that occurs depends on the volume of fluid, the regularity of the exchanges, and the concentration of the fluid. The presence of a catheter presents a risk of peritonitis, as it can introduce bacteria into the abdomen. Peritonitis can be treated by infusing antibiotics directly into the peritoneal cavity via the fluid.

[0096] Aspects of the disclosed subject matter include the following.

[0097] One aspect of the disclosed subject matter provides a device comprising an elongate tubular member having a proximal region, a distal region, a first lumen having a wall without openings extending from the proximal region to the distal region providing a fluid pathway between the first lumen and an exterior, and a second lumen, wherein the proximal region is configured to be engaged with a transfer fitting for controlling fluid flow through the first lumen, the distal region comprising a plurality of perforations in fluid communication with the first lumen and an expandable member comprising an expandable structure, and the second lumen comprises an inflation tube extending from the proximal region of the device to the expandable structure.

[0098] Embodiments of the apparatus include, alone or in any combination:

[0099] The device, wherein a plurality of perforations are disposed at a distal end of the distal region and an expandable structure is disposed proximal to the plurality of perforations.

[0100] A device having a curved distal end containing multiple perforations.

[0101] A device having a spirally configured distal end that includes multiple perforations.

[0102] The device, wherein the expandable structure is disposed at a distal end of the distal region and the perforations are disposed proximal to the expandable structure.

[0103] The device, wherein the expandable structure is disposed longitudinally along a portion of the distal region.

[0104] The device, wherein the expandable structure is disposed on a first portion of the circumference of the distal region and the plurality of perforations is disposed on a second portion of the circumference of the distal region.

[0105] A device having a curved distal region.

[0106] The device, wherein the distal region is configured as a spiral.

[0107] A device, wherein the expandable structure comprises a material selected from the group consisting of nylon, polyamide, polyolefin, polyester, polyurethane, fluoropolymer, polyethylene, polytetrafluoroethylene (PTFE), polyethylene terephthalate (PET), polyvinyl chloride, latex, natural rubber, synthetic rubber, elastomer, silicone, and mixtures and copolymers thereof.

[0108] The device further includes a cuff disposed on the wall of the elongate tubular member in the proximal region.

[0109] The device further includes a second cuff disposed on the wall of the elongate tubular member in the proximal region.

[0110] The device, wherein the expandable structure comprises a balloon.

[0111] The device, wherein the expandable structure includes a sheath defining a cavity containing an open cell foam therein.

[0112] The apparatus further comprises a retractable non-expandable sheath disposed radially outward of the expandable structure.

[0113] Another embodiment is a method for performing peritoneal dialysis comprising inserting a distal region of the device described above through an opening in the abdominal wall of a subject requiring dialysis, introducing fluid into the abdomen through the first lumen, maintaining the fluid within the abdomen for a sufficient time for waste products to diffuse into the fluid from blood vessels surrounding the abdomen, expanding the expandable structure, and removing fluid from the abdomen through the first lumen.

[0114] The method further includes the following embodiments, either alone or in combination:

[0115] The method includes the step of contracting the expandable structure after the fluid is removed from the abdomen.

[0116] A method, wherein the apparatus further comprises a retractable sheath disposed about the expandable structure, the method further comprising retracting the retractable sheath prior to expanding the expandable structure.

[0117] Also provided is a method for treating a subject in need of peritoneal dialysis, comprising inserting a distal region of the above-described device through an opening in the abdominal wall of the subject, expanding the expandable structure through the second lumen, introducing fluid into the abdomen through the first lumen, maintaining the fluid in the abdomen for a time sufficient for waste products to diffuse into the fluid from blood vessels surrounding the abdomen, and removing fluid from the abdomen through the first lumen.

[0118] The method further includes the following embodiments, either alone or in combination:

[0119] The method includes the step of contracting the expandable structure after the fluid is removed from the abdomen.

[0120] A method, wherein the apparatus further comprises a retractable sheath disposed about the expandable structure, the method further comprising retracting the retractable sheath prior to expanding the expandable structure.

[0121] Although preferred embodiments of the invention have been described, it is to be understood that the invention is not so limited and that modifications may be made without departing from the invention. The scope of the invention is defined by the appended claims, and all devices that fall within the meaning of the claims, either literally or equivalently, are intended to be encompassed therein. Moreover, the advantages described above are not necessarily the only advantages of the invention, and it is not necessarily expected that all of the advantages described will be achieved in all embodiments of the invention.

Claims

1. an elongate tubular member comprising a proximal region, a distal region, and a wall defining a first lumen and a second lumen extending from the proximal region to the distal region, a portion of the wall disposed in the distal-most region including a plurality of perforations in fluid communication with the first lumen; an expandable member disposed on the tubular member proximal to the portion of the wall including the plurality of perforations and in fluid communication with the second lumen, the expandable member being air-tight and fluid-tight and comprising a sheath defining a cavity including an open-cell foam, the expandable member being configured in a compressed state for insertion into a body cavity; An apparatus comprising: The device, wherein the first lumen is a fluid lumen and the second lumen is an inflation lumen.

2. The device of claim 1 , wherein the expandable member is disposed longitudinally along a portion of the distal region.

3. The device of claim 1 or claim 2, wherein the expandable member is sized to enclose at least a portion of a circumference of at least a portion of the elongated tubular member.

4. The device of claim 1 , 2 or 3 , wherein the expandable member completely encapsulates at least a portion of the elongated tubular member.

5. The apparatus of any one of claims 1 to 4, wherein the wall containing the plurality of perforations has a curved configuration.

6. The device of any one of claims 1 to 5, wherein the elongated tubular member further comprises at least one cuff disposed on the wall of the elongated tubular member in the proximal region.

7. The device of any one of claims 1 to 6, wherein the wall of the elongate tubular member further comprises a radiopaque stripe extending from the proximal region to the distal region.

8. The apparatus of any one of claims 1 to 7, wherein the elongate tubular member further comprises a retractable sheath.

9. 9. The device of any one of claims 1 to 8, wherein the elongated tubular member further comprises a coupling mechanism operably engaged to the proximal region of the elongated tubular member, the coupling mechanism capable of controlling fluid flow through the first lumen.

10. The device of claim 9 , wherein the coupling mechanism comprises a passageway in fluid communication with the first lumen.

11. The device of claim 9 , wherein the coupling mechanism comprises a passageway in fluid communication with the second lumen.

12. an elongate tubular member comprising a proximal region, a distal region, and a wall including a radiopaque stripe extending from the proximal region to the distal region, the wall defining a first lumen and a second lumen extending from the proximal region to the distal region, the first lumen being a fluid lumen and the second lumen being an inflation lumen, the wall portion disposed at a distal end of the distal region being configured in a helical shape and including a plurality of perforations in fluid communication with the first lumen; an expandable member disposed longitudinally of the tubular member to completely encapsulate at least a portion of the elongated tubular member along a portion of the distal region disposed proximal to the perforated portion of the wall, the expandable member being in fluid communication with a second lumen and being airtight and fluid tight, the expandable member comprising a sheath defining a cavity comprising an open cell foam; a first cuff and a second cuff disposed in spaced relation on a wall of the elongated tubular member in the proximal region; The apparatus of claim 1 , comprising:

13. 13. The device of claim 12, wherein the elongated tubular member further comprises a coupling mechanism operably engaged to the proximal end of the elongated tubular member, the coupling mechanism comprising a first passageway in fluid communication with the first lumen and a second passageway in fluid communication with the second lumen, the coupling mechanism being capable of controlling fluid flow through the first lumen.

14. 9. A kit comprising a device according to any one of claims 1 to 8 and a coupling mechanism configured to engage the device, the coupling mechanism being capable of controlling fluid flow through the first lumen when engaged with the device.

15. The kit of claim 14 , wherein the coupling mechanism comprises a passageway configured to be in fluid communication with the first lumen.

16. The kit of claim 14 , wherein the coupling mechanism comprises a passageway configured to be in fluid communication with the second lumen.

17. The kit of any one of claims 14 to 16, further comprising a stylet for guiding insertion of the catheter into the peritoneal cavity of a subject.

18. The kit of any one of claims 14 to 17, further comprising a cutting tool for forming an opening in the peritoneal cavity for inserting the catheter.

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