WO1990015636A1 - Porous percutaneous access device - Google Patents
Porous percutaneous access device Download PDFInfo
- Publication number
- WO1990015636A1 WO1990015636A1 PCT/AU1990/000242 AU9000242W WO9015636A1 WO 1990015636 A1 WO1990015636 A1 WO 1990015636A1 AU 9000242 W AU9000242 W AU 9000242W WO 9015636 A1 WO9015636 A1 WO 9015636A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- cuff
- tissue
- interface material
- range
- porous
- Prior art date
Links
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M39/00—Tubes, tube connectors, tube couplings, valves, access sites or the like, specially adapted for medical use
- A61M39/02—Access sites
- A61M39/0247—Semi-permanent or permanent transcutaneous or percutaneous access sites to the inside of the body
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M39/00—Tubes, tube connectors, tube couplings, valves, access sites or the like, specially adapted for medical use
- A61M39/02—Access sites
- A61M39/0247—Semi-permanent or permanent transcutaneous or percutaneous access sites to the inside of the body
- A61M2039/0261—Means for anchoring port to the body, or ports having a special shape or being made of a specific material to allow easy implantation/integration in the body
Definitions
- This invention relates to devices for providing
- percutaneous access to the body and more particularly to materials and structures suitable to anchor such devices within the body for substantial periods of time.
- Percutaneous access is often required for the delivery of therapeutic agents, the provision of electrical, pneumatic or similar impulses or the removal of endogenously or
- Continuous ambulatory peritoneal dialysis is an example of a therapy requiring chronic stable percutaneous access. Continuous ambulatory peritoneal dialysis requires
- Dacron Trade Mark
- Pubol A common form of cuff material, Dacron (Trade Mark) is disclosed in relation to a relatively complex "retainer" structure in US 4,278,092 (Borsanyi et al).
- US 3,663,965 discloses a relatively complex cuff which includes what might be termed a disc adapted to extend well away from the tubing which it
- the disc portion includes a plurality of holes adapted to aid the ingrowth of body material.
- the major failure modes of these catheters relate to soft tissue complications such as exit site infection and cuff extrusion which is hypothesised to be primarily due to poor compatibility of the Dacron cuff and/or failure of the cuff to prevent sinus formation.
- the Dacron felt cuff is a woven felt structure and, as such, is not a truly porous structure in the sense used in this specification.
- PCT/US85/01809 (W086/01729) to Yamamoto et al discloses a particular, distendable cuff structure and notes that the surface of the cuff structure must have tissue sealing properties "which can be conferred by (2) the attachment of porous, tissue ingrowth promoting material, such as woven felts, and velours, textured polymers, and foam or spongelike materials, (2) the surface texturing of the sleeve material by high energy bombardment or salting out methods; (3) the attachment or incorporation of tissue adhesive biomolecules such as lectins.”
- Yamamato uses the term "porous" in a loose, broad sense.
- EP0164896 to Thermedics discloses a structure having cavities which are interconnected by a tortuous path.
- the "porosity" of such a structure is somewhat limited.
- percutaneous access device comprising a conduit adapted to be passed through the skin to define a portal to and from the body and a porous cuff of biocompatible material around the conduit; said biocompatible material having a homogeneous interconnected porous structure of the type which can be produced by the replamineform technique; said cuff adapted to be surgically placed so as to anchor said conduit within the body as a result of tissue ingrowth into said cuff.
- pores of the cuff are interconnecting and an analogy between this porous structure may be made, for example with the structure of cancellous or spongy bone, the trabeculae-like structures in this situation being
- the cuff of the invention may be manufactured by established techniques such as the replamineform process in which the skeletal structures of marine invertebrates are used as template molds.
- the replamineform process uses the micro porous skeletal structure of selected marine species as a template to obtain the desired porous network by the process of filling the void spaces in the skeletal structure with the desired biocompatible material and then etching away the skeletal structure itself to leave only the biocompatible material.
- the process is characterised by its ability to produce porous structures of the above described "type. Throughout this specification the use of the term
- porous, interconnected porous structure will be used to denote a porous structure as described by White and capable of being produced by the replamineform process.
- FIG. 3 A photomicrograph of a section though a 200 micron pore size structure produced by the replamineform process is reproduced in Fig. 3 of this specification.
- the reader of this specification is also referred to other illustrations of such porous structures produced by the replamineform process as, for example, illustrated at page 175 of Biomaterials, Vol. 2, July 1981, where a 25 micron pore size structure of the precursor material is shown in section and also to Fig. 1 at page 146 of Biomaterials, Vol. 3, July 1982.
- the reader of this specification is also referred to other illustrations of such porous structures produced by the replamineform process as, for example, illustrated at page 175 of Biomaterials, Vol. 2, July 1981, where a 25 micron pore size structure of the precursor material is shown in section and also to Fig. 1 at page 146 of Biomaterials, Vol. 3, July 1982.
- the reader of this specification is also referred to other illustrations of such porous structures produced by the replamineform process as, for example, illustrated at page 175
- the porous cuff is made of medical grade silicone rubber and is positioned either subcutaneously
- the porous cuff is made from hydroxyapatite or titanium.
- the porous cuff is made from biocompatible material comprising one or more of silicone rubber, semi-rigid polyurethane or other soft, elastomeric material.
- the size and design of the cuff will be dependent upon the size of the conduit transgressing the skin. However, the length will range usually from one to several times the external diameter of the conduit. The thickness of the cuff may be variable depending upon pore size and application.
- Pore size is selected such that it will allow ingrowth and nurturing of fibroblasts which lay down collagen forming fibrous tissue to ankylose the conduit which the porous material surrounds.
- the pore size of the cuff (that is, the average diameter of the irregularly shaped intercommunicating pores within the cuff material) is in the range of 30 to 500 um. More preferably the pore size of the cuff material lies in the range 75 to 300 micrometres and yet more preferably in the range 100 to 220 micrometres. A particular preferred form of the invention has a pore size of approximately 200 micrometres.
- the porosity of the cuff that is the fraction of bulk volume of the material
- occupied by voids is greater than 20%. More preferably it is desired that the porosity of the cuff material lies in the range 25% to 85%.
- said compliance is in the range of 21 to 81 or more preferably 21 to 60 Shore A points based on standard ASTM tests, more preferably in the range 35 to 45 Shore A points and, yet more preferably, approximately 40 Shore A points.
- Substances (and their derivatives or active subunits) which promote the ingrowth of tissue and/or inhibit the growth of bacteria may be associated with the surfaces and interstices of the pores.
- Tissue growth promoters will include the chemotactic factors such as platelet derived growth factor.
- the surface of the pores can be modified to improve their innate bioactivity such as by increasing surface hydrophillicity through treatment with polyglycolic acid.
- Labile substances such as growth factors can be placed within the pores in a supporting medium such as a collagen gel.
- Robust biological active species and substances in terms of their ability to withstand subsequent chemical manipulation may be grafted to or within the polymer surface by a variety of chemical techniques such as plasma grafting or
- Grafting may encompass covalent or more labile intermolecular attractions such as those involving hydrogen bonding, dipole interactions and Van der Waals forces.
- a method of forming a cuff from biocompatible material for enclosing a conduit for the purpose of anchoring said conduit within skin layers and promoting a biological seal comprising forming said biocompatible material in such a manner that its structure includes a plurality of pores which are highly interconnected.
- said method includes use of the replamineform process to produce said biocompatible material.
- tissue interface wherein a tissue seal is formed between a conduit and skin interface, said tissue interface comprising biocompatible material made by the replamineform process whereby a structure having controlled porosity and a compliance in a preselected range is obtained.
- said porosity (that is, the fraction of bulk volume of the material occupied by voids) is greater than 20% and more preferably in the range 25% to 85%.
- said compliance is in the range of 21 to 60 Shore A points based on standard ASTM tests, more preferably in the range 35 to 45 Shore A points and, yet more preferably, approximately 40 Shore A points.
- Fig 1 is a schematic view of a percutaneous access
- FIG. 1 is a view similar to Figure 1 with the
- FIG 3 is a photomicrograph of a 200 micron pore size structure of an embodiment of the structure utilized bv the invention. Description of the Preferred Embodiments
- Fig. 1 shows a percutaneous access device comprising a conduit 10 of appropriate composition and length.
- the catheter is made from silicone silicone and has an outside diameter of between 5 and 7 millimetres.
- the conduit 10 passes through an incision 13 in the skin 11 into the body tissue 14.
- the tube 10 requires to be reliably anchored within the body tissue 14.
- a porous cuff 12 is attached to the periphery of the tube at a location immediately below the skin surface.
- a non-porous sleeve 15 which is integrally connected to the inside surface of the porous cuff 12 is permanently connected to the outer surface of the tube 10 by glue.
- the step of gluing can be performed at the time of manufacture of tube 10 or it can be performed during the operation to insert the tube 10 into the body tissue 14.
- the non-porous sleeve 15 serves to isolate the porous structure of the cuff 12 from the glue.
- Porous material from which the generally cylindrical cuff 12 is made is biocompatible material constructed by the replamineform process so as to provide the biocompatible material with a homogeneous, interconnected porous structure.
- the technique is used for duplicating the
- microstructure of carbonate skeletal components in ceramic, metal or polymer materials allows control of pore size and the size of the interconnection between
- the height (dimension A in Fig. 1) of the generally cylindrical cuff structure is in the range of 0.5 to 2 centimetres.
- Dimension B in Fig. 1 (the thickness of the porous structure of the cuff) is in the range 0.5 millimetre to 3 millimetres.
- the dimension A will be in the range 1 to 5 times the outside diameter of the tublar element enclosed by the cuff.
- the cuff 12 is ideally located within 1 centimetre of the surface of the skin 11. i.e. the top of the cuff 12 as illustrated is within 1 centimeter of the surface of the skin 11.
- the inside diameter of the cuff 12 is selected to match the outside diameter of the tube 10. This dimension will vary according to the task which the tube 10 is to perform.
- the pore size within the porous structure of the cuff 12, when produced according to the replamineform process, is relatively consistent, usually with a standard diviation of 10% of the average pore size of the structure.
- Average pore size can be selected from within the range 30 to 500 microns. Experimental results to date suggest 75 to 300 microns is a preferred pore size range from which to select whilst 100 to 220 microns is the most desired range from which to select. As indicated below, the experimental results show that the very small pore sizes do not allow good fibrous tissue ingrowth whilst very large pore sizes tend to produce structural characteristics which are mechanically not desirable.
- the photomicrograph shown in Fig. 3 is a section through a 200 micron pore size cuff structure made according to the replamineform process from polysyloxane. That cross section is typical of cross sections to be expected in the porous cuff structure 12 of embodiments of the invention.
- the replamineform process predominantly allows control over pore size and pore size consistency and pore
- control is also exerted over the "porosity” (defined as the fraction of the bulk volume of the material occupied by voids) cf the biocompatible material and, by allowing a wide choice of biocompatible material also allows control over the compliance of the material.
- porosity defined as the fraction of the bulk volume of the material occupied by voids
- the porosity should be greater than 20% and, ideally, should lie in the range 25 to 85%.
- the porous structure of the cuff is made from elastomeric material.
- the compliance should be in the range 21 to 60 Shore A points and ideally in the range 35 to 45 Shore A points.
- the structure made from silicone rubber previously described and illustrated in Fig. 3 has a
- Fig. 2 discloses a second embodiment of the invention where like parts have the same numbers as in Fig. 1.
- the structure and its composition is in all respects the same as that described with respect to Fig. 1, save that the cuff 12 is placed percutaneously so that it protrudes a few
- Subcutaneously positioned discs were placed in rabbits above the superficial fascia to study the importance of pore structure and pore size on tissue growth.
- the trial sample cuff structures were made from silicone rubber, polyurethane and hydroxyapatite using the replamineform process so as to produce sample structures having respectively 20 micron average pore size, 100 micron average pore size, 200 micron average pore size and 500 micron average pore size.
- the 20 micron pore size samples made from each of the materials showed little fibrous tissue ingrowth into the pores after four weeks implantation. It appeared that the pore size was simply too small to be effective.
- the 100 micron structures performed well giving mature collagen and good ingrowth after four weeks with the majority of pores filled.
- the hydroxyapatite caused the least
- the 200 micron samples performed much the same as the 100 micron samples but with quality of ingrowth being a little better and the amount of inflammation being a little less. These samples produced the optimum results.
- hydroxyapatite samples were made with a 500 micron pore size. The results of this structure were generally the same as for the 100 and 200 micron pore size hydroxyapatite samples. However, hydroxyapatite is bioactive and dissolves in the tissues over time. The 500 micron hydroxyapatite sample showed a greater predeliction to this behaviour than the smaller pore size hydroxyapatite samples.
- silicone rubber was found to have better inflammation behaviour than poiyurethane. Hydroxyapatite probably performed the best as far as inflammation results are concerned but is an inherently brittle material which does not have the desirable compliance characteristics of silicone rubber or poiyurethane.
- the cuffs used included an integral bottom flange made from the same material as the rest of the porous structure of the cuff and extending approximately 4 millimetres radially away from the cuff cylindrical surface.
- the flanges were incorporated merely as a substitute for the stabilising effect normally provided by the tube 10 to which the cuff 12 is attached in normal usage.
- Cuff structures of Dow Corning Q7-4840 silicone rubber and poiyurethane, both of 100 micron average pore size and 200 micron average pore size were made
- a cylindrical cuff as generally illustrated and described in respect of Fig. 1 or Fig. 2 and having a cuff porous structure as illustrated in section in Fig. 3 was prepared from Dow Corning Q7-4840 silicone rubber porous material made using the replamineform process.
- replamineform process was carried out so as to produce a cuff having a homogeneous, interconnected porous structure having a compliance of approximately 40 Shore A points, a porosity of approximately 30% and a pore size of approximately 200 micrometers.
Abstract
Description
Claims
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AUPJ454789 | 1989-06-02 | ||
AUPJ4547 | 1989-06-02 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1990015636A1 true WO1990015636A1 (en) | 1990-12-27 |
Family
ID=3773966
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/AU1990/000242 WO1990015636A1 (en) | 1989-06-02 | 1990-06-01 | Porous percutaneous access device |
Country Status (3)
Country | Link |
---|---|
EP (1) | EP0431102A4 (en) |
CA (1) | CA2033336A1 (en) |
WO (1) | WO1990015636A1 (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2003082366A1 (en) * | 2002-03-28 | 2003-10-09 | Japan As Represented By President Of National Cardiovascular Center | Tissue engineering scaffold material, aritficial vessel, cuff member and coating for implants |
US6636740B1 (en) | 1998-06-16 | 2003-10-21 | Ericsson Inc. | Apparatus and methods for position computation based on broadcast initialization data |
EP1731191A1 (en) * | 2004-03-08 | 2006-12-13 | Japan as represented by president of National Cardiovascular Center | Cuff member |
FR3077207A1 (en) * | 2018-01-29 | 2019-08-02 | Franck Zinzindohoue-Marsaudon | CATHETER WITH CARBON-CARBON COMPOSITE SLEEVE |
Citations (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3699956A (en) * | 1970-10-01 | 1972-10-24 | Tecna Corp | Percutaneous lead device |
AU5161179A (en) * | 1978-10-10 | 1980-04-17 | Ici Ltd. | Fibrous surfaces for contact with living tissue |
US4278092A (en) * | 1979-07-05 | 1981-07-14 | American Hospital Supply Corporation | Peritoneal catheter |
US4321914A (en) * | 1980-04-22 | 1982-03-30 | W. L. Gore & Associates, Inc. | Percutaneous conduit having PTFE skirt |
WO1983001572A1 (en) * | 1981-11-07 | 1983-05-11 | Juhasz, Lazslo | Improved continuous ambulatory peritoneal dialysis system |
WO1985003445A1 (en) * | 1984-02-03 | 1985-08-15 | Medinvent S.A. | A multilayered prosthesis material and a method of producing same |
WO1986001729A1 (en) * | 1984-09-21 | 1986-03-27 | Ronald Kenichi Yamamoto | Positionable tissue interfacing device for the management of percutaneous conduits |
WO1986002843A1 (en) * | 1984-11-08 | 1986-05-22 | WALLSTÉN, Hans, Ivar | A method of producing a mono- or multilayered prosthesis material and the material hereby obtained |
US4668222A (en) * | 1984-05-25 | 1987-05-26 | Thermedics Inc. | Percutaneous access device with removable tube |
EP0269449A2 (en) * | 1986-11-26 | 1988-06-01 | BAXTER INTERNATIONAL INC. (a Delaware corporation) | Porous flexible radially expanded fluoropolymers and process for producing the same |
AU1076588A (en) * | 1987-01-27 | 1988-07-28 | Asahi Kogaku Kogyo Kabushiki Kaisha | Implant material and method of producing the same |
AU3503489A (en) * | 1988-05-20 | 1989-11-23 | Asahi Kogaku Kogyo Kabushiki Kaisha | Transcutaneous device |
EP0367354A1 (en) * | 1988-11-02 | 1990-05-09 | Stichting voor Materiaalkunde Vrije Universiteit Amsterdam "MAVU" | A percutaneous implant |
-
1990
- 1990-06-01 CA CA 2033336 patent/CA2033336A1/en not_active Abandoned
- 1990-06-01 EP EP19900908419 patent/EP0431102A4/en not_active Withdrawn
- 1990-06-01 WO PCT/AU1990/000242 patent/WO1990015636A1/en not_active Application Discontinuation
Patent Citations (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3699956A (en) * | 1970-10-01 | 1972-10-24 | Tecna Corp | Percutaneous lead device |
AU5161179A (en) * | 1978-10-10 | 1980-04-17 | Ici Ltd. | Fibrous surfaces for contact with living tissue |
US4278092A (en) * | 1979-07-05 | 1981-07-14 | American Hospital Supply Corporation | Peritoneal catheter |
US4321914A (en) * | 1980-04-22 | 1982-03-30 | W. L. Gore & Associates, Inc. | Percutaneous conduit having PTFE skirt |
WO1983001572A1 (en) * | 1981-11-07 | 1983-05-11 | Juhasz, Lazslo | Improved continuous ambulatory peritoneal dialysis system |
WO1985003445A1 (en) * | 1984-02-03 | 1985-08-15 | Medinvent S.A. | A multilayered prosthesis material and a method of producing same |
US4668222A (en) * | 1984-05-25 | 1987-05-26 | Thermedics Inc. | Percutaneous access device with removable tube |
WO1986001729A1 (en) * | 1984-09-21 | 1986-03-27 | Ronald Kenichi Yamamoto | Positionable tissue interfacing device for the management of percutaneous conduits |
WO1986002843A1 (en) * | 1984-11-08 | 1986-05-22 | WALLSTÉN, Hans, Ivar | A method of producing a mono- or multilayered prosthesis material and the material hereby obtained |
EP0269449A2 (en) * | 1986-11-26 | 1988-06-01 | BAXTER INTERNATIONAL INC. (a Delaware corporation) | Porous flexible radially expanded fluoropolymers and process for producing the same |
AU1076588A (en) * | 1987-01-27 | 1988-07-28 | Asahi Kogaku Kogyo Kabushiki Kaisha | Implant material and method of producing the same |
AU3503489A (en) * | 1988-05-20 | 1989-11-23 | Asahi Kogaku Kogyo Kabushiki Kaisha | Transcutaneous device |
EP0367354A1 (en) * | 1988-11-02 | 1990-05-09 | Stichting voor Materiaalkunde Vrije Universiteit Amsterdam "MAVU" | A percutaneous implant |
Non-Patent Citations (3)
Title |
---|
Bulletin de la Societe Chimique de France, Volume 7-8, 1985 (Nancy) J C HEUGHEBAERT et al 'Bioceramiques a Base de Phosphate de Calcium', see pages 528-531, especially page 529 * |
See also references of EP0431102A4 * |
Vascular Grafting: Clinical Applications and Techniques, Creigton B Wright (Ed), Boston, J Wright PSG Inc 1983. RODNEY A WHITE 'Evaluation of Small Diameter Graft Parameters using Replamineform Vascular Prostheses'. see chapter 25 * |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6636740B1 (en) | 1998-06-16 | 2003-10-21 | Ericsson Inc. | Apparatus and methods for position computation based on broadcast initialization data |
WO2003082366A1 (en) * | 2002-03-28 | 2003-10-09 | Japan As Represented By President Of National Cardiovascular Center | Tissue engineering scaffold material, aritficial vessel, cuff member and coating for implants |
AU2003221090B2 (en) * | 2002-03-28 | 2008-11-20 | Bridgestone Corporation | Tissue engineering scaffold material, artificial vessel, cuff member and coating for implants |
AU2003221090B9 (en) * | 2002-03-28 | 2009-05-21 | Bridgestone Corporation | Tissue engineering scaffold material, artificial vessel, cuff member and coating for implants |
AU2003221090C1 (en) * | 2002-03-28 | 2009-11-05 | Bridgestone Corporation | Tissue engineering scaffold material, artificial vessel, cuff member and coating for implants |
EP1731191A1 (en) * | 2004-03-08 | 2006-12-13 | Japan as represented by president of National Cardiovascular Center | Cuff member |
EP1731191A4 (en) * | 2004-03-08 | 2010-01-27 | Japan Government | Cuff member |
FR3077207A1 (en) * | 2018-01-29 | 2019-08-02 | Franck Zinzindohoue-Marsaudon | CATHETER WITH CARBON-CARBON COMPOSITE SLEEVE |
Also Published As
Publication number | Publication date |
---|---|
EP0431102A1 (en) | 1991-06-12 |
EP0431102A4 (en) | 1992-01-08 |
CA2033336A1 (en) | 1990-12-03 |
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