Medical device, in particular for treating fistulas

Abstract

A medical device includes a fluid collection element, a fluid communication element and a pulling element. The pulling element is attached to a distal end of the fluid collection element and/or fluid communication element. The medical device can be included in a medical kit.

Claims

1. A device for treating a fistula comprising: a) a fluid collection element comprising an open cell or porous structure, the fluid collection element comprising a proximal fluid collection portion and a distal fluid collection portion, b) a fluid communication element comprising a tubular body extending through the proximal fluid collection portion of the fluid collection element, the tubular body comprising a proximal tube section and a distal tube section, and c) a pulling element comprising a proximal section and a distal section, the proximal section of the pulling element being attached to or around the distal tube section of the fluid communication element, the distal section of the pulling element comprising a distal end extending away from the distal tube section of the fluid communication element and configured to be pulled by a grasping instrument to place the device inside a fistula, an entirety of the pulling element being located outside of the proximal tube section of the fluid communication element, the device further comprising: a first attachment element secured around the proximal fluid collection portion to axially fix the proximal fluid collection portion to the fluid communication element, and a second attachment element secured around the distal fluid collection portion to axially fix the distal fluid collection portion to the fluid communication element, so that the fluid collection element is axially fixed relative to the fluid communication element.

2. The medical device according to claim 1, wherein the pulling element comprises a loop portion.

3. The medical device according to claim 1, wherein the pulling element comprises a non-looped portion.

4. The medical device according to claim 3, wherein the pulling element is attached to the fluid collection element via the non-looped portion.

5. The medical device according to claim 1, wherein the pulling element engages at least one hole and/or at least one perforation that is arranged on the distal tube section of the fluid communication element.

6. The medical device according to claim 1, wherein the pulling element is attached to or around the distal tube section of the fluid communication element by a knot, thread, clip and/or material bonding engagement.

7. The medical device according to claim 1, wherein the pulling element is attached to the distal fluid collection portion of the fluid collection element by knotting.

8. The medical device according to claim 1, wherein the pulling element is a thread.

9. The medical device according to claim 1, wherein the distal tube section of the fluid communication element is surrounded by the fluid collection element.

10. The medical device according to claim 1, wherein the distal tube section of the fluid communication element comprises holes and/or perforations.

11. The medical device according to claim 10, wherein the holes and/or perforations in the distal tube section of the fluid communication element extend along an entire length of the fluid collection element.

12. The medical device according to claim 1, wherein the fluid communication element comprises a connector.

13. A medical kit comprising a medical device according to claim 1 and at least one component selected from a group consisting of negative pressure or vacuum source, extension tube, fluid collection vessel, sterile filter, grasping instrument, lubricant, syringe, suture, sealing patch, scissors and stapler.

14. The medical device according to claim 1, further comprising a plurality of attachment elements secured around the fluid collection element at a plurality of fixation sites along a length of the fluid collection element between the first attachment element and the second attachment element to axially fix the fluid collection element to the fluid communication element.

15. The medical device according to claim 14, wherein the plurality of attachment elements constrict the fluid collection element at the plurality of fixation sites.

16. The medical device according to claim 1, wherein the entirety of the pulling element is located outside of the proximal tube section and distal tube section of the fluid communication element.

Description

BRIEF DESCRIPTION OF THE DRAWING FIGURES

(1) The figures schematically show the following:

(2) FIG. 1: an embodiment of a medical device according the present invention and

(3) FIG. 2a-d treatment of an anal fistula by means of a medical device according to the present invention.

DETAILED DESCRIPTION

(4) FIG. 1 schematically shows a medical device 100 according to the present invention.

(5) The medical device comprises a fluid collection element 110, a fluid communication element 120 and a pulling element 130.

(6) The fluid collection element 110 may have a foam structure, in particular an open-cell foam structure, preferably made of polyurethane.

(7) The fluid communication element 120 has a tubular shape and is preferably configured as a drainage tube.

(8) The pulling element 130 is preferably configured as a thread, in particular as a multiple thread, i.e. multifilament. More preferably, the pulling element 130 may be a braided multifilament. For example, the pulling element 130 may be a braided polyethylene terephthalate thread.

(9) The pulling element 130 comprises a loop portion 132 and a non-looped portion 134. The loop portion 132 is preferably formed by an attachment element 133, in particular knot.

(10) While the loop portion 132 is arranged at a distal end 131 of the pulling element 130, the pulling element is attached via its non-looped portion 134 to the distal end 111 of the fluid collection element 110. Preferably, the pulling element 130 is attached to the distal end 111 of the fluid collection element 110 by means of knotting knot, preferably of the pulling element 130. In other words, it is preferred that the pulling element 130 is knotted over the distal end 111.

(11) Advantageously, the pulling element 130 facilitates guidance of the medical device 100 through a fistula canal.

(12) The fluid collection element 110 may be attached to the fluid communication element 130 several attachment elements 135, in particular in the form of knots. The attachment elements 135 may constrict the fluid collection element 110 at the respective fixation sites. Advantageously, the attachment elements 135 effect connection between the fluid collection element 110 and the fluid communication element 120. Further, the medical device 100 can better withstand the forces exerted during the introduction and removal of the medical device 100, if the medical device 100 comprises several attachment elements 135.

(13) Preferably, the fluid collection element 110 serves the purpose to prevent the fluid communication element 120 form being clogged when negative pressure or vacuum is applied.

(14) Furthermore, the fluid collection element 110 advantageously distributes the pressure through the length of a fistula canal, once negative pressure or vacuum is applied.

(15) Furthermore, a porosity or open cell structure of the fluid collection element 110 in combination with a negative pressure or vacuum supplied through the fluid communication element 120 may advantageously enable and/or promote tissue in-growth and liquid collection.

(16) Preferably, only a distal portion 121 of the fluid communication element 120 is engirded by the fluid collection element 110.

(17) In order to allow transfer of body liquids taken up by the fluid collection element 110 into the fluid communication element 120, in particular into a canal 123 of the fluid communication element, the distal portion 121 comprises several holes 125. Alternatively or additionally, the distal portion 121 may comprise several perforations. Typically, the holes 125 are arranged along the distal portion 121. Advantageously, the holes 125 prevent the fluid communication element 120 from being blocked once vacuum is applied.

(18) Typically, the fluid communication element 120 is adapted to conduct a negative pressure or vacuum to a fistula canal.

(19) Further, a connector 140, in particular a luer-lock connector, may be attached to the proximal end 129 of the fluid communication element. The connector 140 is preferably adapted to connect the fluid communication element 120 to an extension tube (not shown). The extension tube is typically adapted to facilitate connection with a negative pressure or vacuum pump.

(20) FIG. 2a schematically shows an anal fistula 10. The fistula 10 is featured by a skin opening 12 and a rectal opening 14.

(21) To treat the anal fistula 10, a medical device 100 according to the present invention is placed inside the fistula 10. The medical device 100 comprises a fluid collection element 110, a fluid communication 120 and a pulling element 130. The placement of the medical device 100 inside the fistula 10 is expediently achieved by means of a grasping device 200 (see FIG. 2b). Thus, the medical device 100 can be placed inside the fistula 10 (see FIG. 2c).

(22) After placement, the medical device 100 can be trimmed, by way of example, by means of a scissors 300, as shown in FIG. 2d.

(23) After placing and optionally trimming of the medical device 100, the rectal opening 14 and the skin opening 12 are sealed. For example, the rectal opening 14 can be sealed by means of suturing or stapling, while the skin opening 12 can be sealed by means of a patch.

(24) After sealing of the fistula's ends, the fluid communication element 120 is connected to a negative pressure or vacuum source, in particular to a negative pressure or vacuum pump.

EXAMPLES

(25) 1. Concept of Manufacturing

(26) Blocks of polyurethane foam were manufactured by an external supplier with dimensions of 100×450×735 mm. Three types of foams (orange, black and silver foams) of the same material were received. The characteristics of the foam types are detailed in table 1:

(27) TABLE-US-00001 TABLE 1 orange black silver Foam density  23 ± 2.5 kg/m.sup.3  23 ± 2.5 kg/m.sup.3   28 ± 3.0 kg/m.sup.3 Compression load 3.9 ± 0.8 kPa 3.6 ± 1.0 kPa 2.95 ± 0.85 kPa Tensile strength min. 60 kPa min. 60 kPa min. 75 kPa Elongation at break min. 100% min. 100% min. 95%

(28) Cylindrical foams were mechanically cut from the blocks by means of cutting dyes. To do so, two types of dyes were used: a dye having a diameter of 12 mm for the external diameter of the polyurethane foam and a dye having a diameter of 2 mm for the inner hollow diameter of the polyurethane foam. The length of the cylinder was the 100 mm depth of the foam block. As an alternative, the foam cutting may be accomplished by means of a hydraulic press.

(29) For the fluid communication element, a CH05 redon tube was cut from an original length of 500 mm to 440 mm (reducing the length of perforations from 150 mm to 90 mm). This component was cut in order to adapt it to the cylindrical foam of 100 mm. Additionally, the redon tube was marked to position the fixation points with the sutures.

(30) The already cut redon drain was then introduced through the inner canal of the cylindrical foam. Both components were fixed using a braided non-absorbable polyester suture (USP 0). This suture passed through the sponge and orifice of 1 mm of the redon drain avoiding to pierce the tube with the suture needle. An overhand knot was performed and two square knots were performed on the opposed sides. The remaining ends of the suture were cut with scissors. This procedure was repeated a total of 4 times along the cylindrical foam, following the marks on the redon drain.

(31) The fifth fixation point at the distal part of the device differed from the ones described above. Unlike the other fixation points, once the square knots were performed, one of the suture ends was not cut. This uncut end was used to create the pulling loop with a total length of 200 mm and a loop of 35 mm. This loop was performed using a double overhand knot, the remaining suture was cut with scissors.

(32) Further, a standard male luer-lock connector was assembled to the remaining distal end of the redon drain by mechanical interference with a CH05 to CH06 adapter.

(33) 2. Usability of the Concept

(34) A laboratory model of a complex fistula canal was manufactured by using transparent polyurethane rubber molding. The material was soft (Shore A 20) in order to stimulate its in vivo performance. This model contained a curved canal of 80 mm in length and a diameter of 8 mm.

(35) At first, a multifilament suture was introduced through the fistula canal as seton. This corresponds to the treatment of fistulas, where the first procedure is to maintain the fistula canal open for cleansing.

(36) Afterwards, a medical device according to the present invention was knotted from the pulling loop to the already introduced seton. In order to facilitate the introduction of the medical device, the cylindrical foam was impregnated with an Askina® hydrogel. The seton and pulling knot acted as a guide to position the cylindrical foam through the fistula canal. Once the foam covered all the fistula canal, the distal part with the pulling element was removed taking into account that no foam remained outside of the defect.

(37) In order to apply a vacuum pressure on the canal, it was required to close both openings of the defect. The proposed method of closure by the surgeons is to use a suture in both openings. The laboratory model cannot be sutured, as it would tear the material, therefore instead of sutures it was used polyurethane adhesive pads already used on vacuum therapy for open approaches.

(38) The standard male luer-lock connector was connected to an extension tube, already used for wound drainage. Subsequently, the extension tube was connected to a digital vacuum pump with a set point of 175 mmHg of pressure (absolute). The pump was started and the fistula canal was reduced due to the actuation of the vacuum through the whole defect.