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  Dialysis catheterUSPTO Application #: 20080108969Title: Dialysis catheter Abstract: A catheter assembly includes catheter having proximal and distal ends and at least one lumen extending between the ends. At least one end of the catheter is formed from a material that can be trimmed to achieve a selected length for the catheter. A tubular connector is telescoped over the catheter and a hub is joined to the tubular connector. Proximal portions of the hub are configured for connection to a medical apparatus. A cuff is mounted around the tubular connector or the catheter. The cuff is formed from a material that will permit or promote the growth of scar tissue for anchoring the catheter device at least on a semi-permanent basis in a patient. (end of abstract) Agent: Casella & Hespos - New York, NY, US Inventor: Andrew Kerr USPTO Applicaton #: 20080108969 - Class: 604500000 (USPTO) Related Patent Categories: Surgery, Means For Introducing Or Removing Material From Body For Therapeutic Purposes (e.g., Medicating, Irrigating, Aspirating, Etc.), Treating Material Introduced Into Or Removed From Body Orifice, Or Inserted Or Removed Subcutaneously Other Than By Diffusing Through Skin, Method The Patent Description & Claims data below is from USPTO Patent Application 20080108969. Brief Patent Description - Full Patent Description - Patent Application Claims
[0001] This application is a continuation-in-part of U.S. patent application Ser. No. 11/807,575, which in turn is a divisional of U.S. patent application Ser. No. 11/287,789 now U.S. Pat. No. 7,258,685. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The invention relates to a catheter that can be used for dialysis or for other procedures where the catheter is implanted for an extended period of time. [0004] 2. Description of the Related Art [0005] Dialysis and some chemotherapy regimens require a catheter to be implanted in a patient for an extended time (e.g., several weeks, several months or longer). Catheters for dialysis extend from an externally accessible location on the patient (typically on the chest) to a location where there is a high flow of blood (typically near the heart). The high blood flow enables a sufficient volume of blood to be processed through the catheter and cleaned by the dialysis machine. Catheters used for chemotherapy and other drug administration purposes are extended from an externally accessible location on the patient to a location where the drug is likely to be most effective. The following discussion will pertain mostly to catheters intended for dialysis. However, the subject invention is applicable to all catheters that are implanted for an extended time. [0006] A discussion of catheters is provided in Venous Catheters A Practical Manual by Pieters et al. Chapter 4 of that work is entitled Central Venous Catheters: Materials, Designs and Selection by Matthew A. Mauro, and the disclosure of that Chapter 4 is incorporated herein by reference. [0007] Briefly, the distal end of a dialysis catheter should be placed close to the heart for optimum exchange of blood. Doctors typically want to know the location of the distal end of the dialysis catheter with considerable precision. The proximal end of the dialysis catheter desirably is at a location that can be accessed conveniently during dialysis and that is unobtrusive between the periodic dialysis procedures. Many doctors choose to direct the dialysis catheter through the jugular vein. However, the neck certainly is not the unobtrusive location for keeping the proximal end of the dialysis catheter between the periodic dialysis procedures. [0008] The dialysis catheter typically is formed from a flexible material, such as silicone. A typical medical procedure for implanting a dialysis catheter involves first placing a small incision in the skin of the neck over the jugular vein. Subsequently, the jugular vein is cannulated. A peelable introducer sheath then is advanced an appropriate distance into the blood vessel so that the end of the catheter is at the precise position preferred by the doctor. The doctor then employs a tunnel dilator to create a subcutaneous tunnel that permits the proximal end of the catheter to be at a less obstrusive position. The subcutaneous tunnel typically extends slightly below the skin from a location on the chest and under the clavicle to a location where the catheter has been introduced into the jugular. The doctor directs the catheter through the tunnel, to the neck, through the incision in the neck and through the introducer sheath. The introducer sheath then is removed. A hub at the proximal end of the catheter may include a Luer fitting that enables the proximal end of the catheter to be placed in communication with the dialysis machine. Several closure means are provided on or near the proximal end of the catheter to prevent unintended blood loss between the periodic dialysis procedures. [0009] Blood pressure and other forces within the body tend to urge the catheter from the body. Hence, proper anchoring is important. One common anchoring means provides a cuff extending around the portion of the catheter in the tunnel that extends from the upper chest to the neck of the patient. The cuff typically is formed from polyester. Scar tissue accumulates around the cuff and functions to hold the catheter in place. The scar tissue may also function as a barrier to bacterial infection. The scar tissue results in at least a semi-permanent anchoring of the catheter. In this regard, semi-permanent means that the catheter will remain in the patient until the cuffed portion of the catheter is dissected from the patient. This dissection can be complicated. [0010] Dialysis catheters vary considerably from one manufacturer to another. However, a common requirement for virtually all dialysis catheters is an ability to locate the distal end of the catheter and the cuff with considerable precision. Accordingly, the doctor has limitations on the distance between the distal tip of the catheter and the cuff depending upon physical characteristics of the patient. A smaller patient will require a smaller tip-to-cuff distance, while a larger patient will require a larger tip-to-cuff distance. In view of these physical differences between patients, most dialysis catheter manufacturers provide catheters with different tip-to-cuff length. Accordingly, hospitals must maintain an appropriate inventory of different length dialysis catheters and the doctor must ensure that a catheter of appropriate length is available for implementation. There are costs and complications associated with a need to maintain an inventory of different products. [0011] Compromises often must be made when a doctor selects a dialysis catheter from an inventory of catheters with different lengths. In this regard, dialysis catheters often come with tip-to-cuff lengths of 19 cm, 23 cm, 28 cm and 32 cm. A selection of a catheter of one of these lengths may require the doctor to move the tip or the cuff from its optimal position. [0012] Arrow Cannon markets a dialysis catheter with most of the features described above. The Arrow Cannon catheter is promoted as having an ability to assure accurate tip placement. In this regard, the tip of the catheter is placed in the jugular in the manner described above. Proximal portions of the catheter then are urged in a retrograde direction through the tunnel from the neck to the selected location on the chest. The portion of the catheter emerging from the chest then is cut. A compression cap and compression sleeve are mounted separately to the cut proximal end of the catheter and a hub is threadedly engaged with the compression cap. The above-described Arrow Cannon catheter has the above-described problems associated with inventory management. Additionally, even though the tip may be positioned accurately, the cuff location is dependent upon the different tip-to-cuff dimensions in the inventory. Additionally, the retrograde movement of the catheter through the tunnel requires a technique that many doctors are not accustomed to. Furthermore, the intraoperative assembly of the compression sleeve with the compression cap requires more procedural steps and takes additional time. [0013] U.S. Pat. No. 5,989,213 relates to a dialysis catheter with a guide tube that fits into the blood vessel. A tissue ingrowth member is secured to proximal portions of the guide catheter for affixation to the subcutaneous tissue. Thus, distal portions of the guide catheter of U.S. Pat. No. 5,989,213 reside in the blood vessel and proximal portions of the guide catheter are secured to the subcutaneous tissue. The dialysis catheter then is passed through the guide catheter. The distal end of the dialysis catheter is disposed at an appropriate location in the circulatory system, and distally of the distal end of the guide catheter. Proximal ends of the dialysis catheter are disposed externally on the patient, and proximally of the proximal end of the guide catheter. The system shown in U.S. Pat. No. 5,989,213 permits a desired distance between the distal tip of the catheter and the tissue ingrowth cuff. However, the system shown in U.S. Pat. No. 5,989,213 is not trimmable and hence requires an extensive inventory of catheters of different length to ensure that an excess of the catheter is not disposed externally of the patient. [0014] Accordingly, it is an object of the subject invention to provide an improved catheter that can be implanted for an extended time, such as a dialysis catheter. [0015] Another object of the subject invention is to provide a catheter that substantially avoids the need to maintain a significant inventory, while permitting precise positioning of both the tip and the cuff. [0016] A further object of the invention is to provide a catheter that is convenient to implant and that ensures a precise exit site on the chest for the catheter. SUMMARY OF THE INVENTION [0017] The subject invention is directed to a catheter assembly. The assembly includes a catheter with a proximal end, a distal end and at least one lumen extending therethrough. Catheters intended for use with a dialysis apparatus preferably include at least two lumens extending between the proximal and distal ends. In this context, the distal end of the catheter is considered to be the end that is positioned at an appropriate location in the patient, such as in a major blood vessel near the heart. The proximal end of the catheter is considered the end disposed externally of the patient and near the doctor who is performing the implantation. At least the proximal parts of the catheter are formed from a material that is easily trimmable. [0018] The catheter assembly further includes a means for promoting growth of tissue for fixing the catheter at a selected location relative to a subcutaneous tunnel formed for implantation of the catheter. The means for promoting growth of tissue may be formed from or treated with a fibrosing agent. Fibrosing agents include, but are not limited to silk, collagen, talc, talcum powder, beryllium, copper, silica, quartz, EVA, PLA, polyurethane and polymerized drug compositions. Preferably the means for promoting growth of tissue comprises a cuff mounted around or near the catheter either intraoperatively or immediately prior to implantation. The cuff preferably has a first orientation where the cuff is movable relative to the catheter and a second orientation where the cuff is fixed relative to the catheter. For example, the cuff initially may be a substantially linear structure with opposite first and second ends. The cuff is deformable or deflectable from the initial linear condition into an annular condition. Additionally, the opposed ends of the cuff are securely connectable to one another so that the cuff can be secured around the catheter. The dimensions of the cuff are selected to ensure secure mounting of the cuff around the catheter without constricting the flow of fluid through the catheter. The structure for locking the opposite ends of the cuff together may include interengageable teeth such as the interengagement employed on a wire wrap. Alternatively, the opposed ends of the cuff can have a projection and an aperture respectively that engage much in the manner of a dovetail connection. The connection and mounting of the cuff may be similar to the connection and mounting of band clamps, hose clamps, tube clamps, J-type clamps, one-ear clamps, two-ear clamps and other clamps that secure a flexible member around the outer circumference of a cylindrical member. Such connectors are shown in the MSC Industrial Supply Co. catalog, the disclosure of which is incorporated herein by reference. [0019] The cuff may be engaged directly on the catheter. However, a preferred embodiment includes a subcutaneous tube that is telescoped over the proximal end of the catheter, and the cuff is engaged around portions of the subcutaneous tube that are telescoped over the proximal end of the catheter. The proximal end of the catheter and the subcutaneous tube may have smooth tubular surfaces that telescope into engagement with one another. The assembly may then include a compression cap and a compression sleeve. A Luer hub can be threaded into engagement with the compression cap to deform the compression sleeve sufficiently for interengagement with the catheter and the subcutaneous tube. The compression sleeve preferably is pre-assembled with the compression cap in a manner that substantially prevents axial movement between the compression sleeve and the compression cap while permitting the compression sleeve to rotate relative to both the catheter and the compression cap. Hence, the doctor is not required to assemble the compression sleeve with the compression cap intraoperatively or immediately prior to implementation. Additionally, the ability of the compression sleeve to rotate relative to the compression cap and the catheter prevents the creation of a torque that could twist and constrict or damage the catheter. Various other optional connections between the catheter and the subcutaneous tube may be similar to couplings in the above-referenced MSC Industrial Supply Co. catalog, the disclosure of which is incorporated herein by reference. [0020] An alternate version of the catheter assembly may include may include a cuff tube with a proximal end, a distal end and a lumen extending between the ends. The lumen is configured so that the cuff tube can be telescoped over proximal portions of the catheter. The above described cuff may be mounted to an appropriate location on the outer periphery of the cuff tube. In this regard, the cuff tube can be formed with surface configurations on the outer periphery for positioning and holding the cuff. In other embodiments, the cuff may be premounted to a selected location on the cuff tube. The premounting of the cuff on the cuff tube can be achieved, for example, by adhesive. The cuff tube further may include a hub mounting structure at a location on the outer periphery near the proximal end. Additionally, the cuff tube may include means for constricting portions of the cuff tube into a secure mechanical and fluid tight engagement with the catheter. The hub of this embodiment is configured for secure mounting over proximal portions of the cuff tube. The mounting may be achieved by a snapped engagement of the hub mounting structure on the cuff tube with corresponding structure on the hub. The assembly of this embodiment is employed by initially positioning the catheter as described above. The cuff tube then is slid over proximal portions of the catheter and the attachments means near proximal portion of the cuff tube are tightened to achieve secure engagement of the cuff tube with the catheter. Portions of the catheter that extend proximally beyond the cuff tube then are trimmed. The hub then is mounted over and secured to the cuff tube. The hub can be configured to mount over or into proximal portions of the cuff tube. Additionally, engageable regions of cuff tube and the hub can be configured to compress the cuff tube or the hub inwardly to achieve a secure mechanical and fluid tight interconnection between the cuff tube, the catheter and the hub. This embodiment can avoid the need for a separate attachments means to secure the cuff tube to the catheter. [0021] Another preferred embodiment of the invention provides a catheter with a proximal end configured with a plurality of undulations. Each undulation may include a conically sloped proximal face and a radially aligned distal face. The catheter may be employed with a hub having an inner tubular surface with internal undulations configured for mating with the outer surface configuration on the proximal end of the catheter. The conical and radial surfaces on the undulations on the catheter and the hub are oriented and configured so that the catheter and the hub can be telescoped together easily (i.e., engagement of the conical surfaces), but cannot be separated (i.e., engagement of the radial surfaces). The above-described cuff can be mounted around either a portion of the catheter or a portion of the hub. The hub may include a notch for affixing the cuff at a fixed axial position on the hub. [0022] In an alternate embodiment, the proximal end of the catheter can be formed with an array of external threads and the interior of the hub can be formed with an array of internal threads that can be mated with the threads on the catheter. The cuff can be the above-described cuff that initially is substantially linear and that is mounted subsequently around the catheter or the hub. Alternatively, the cuff can be provided with its own internal array of threads for mounting over the proximal end of the catheter or over the hub. Continue reading... Full patent description for Dialysis catheter Brief Patent Description - Full Patent Description - Patent Application Claims Click on the above for other options relating to this Dialysis catheter patent application. ###  How KEYWORD MONITOR works... a FREE service from FreshPatents1. Sign up (takes 30 seconds). 2. Fill in the keywords to be monitored. 3. Each week you receive an email with patent applications related to your keywords. Start now! - Receive info on patent apps like Dialysis catheter or other areas of interest. ### Previous Patent Application: Pump cassette with spiking assembly Next Patent Application: Control of drug administration Industry Class: Surgery ### FreshPatents.com Support Thank you for viewing the Dialysis catheter patent info. 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