GB2369591A

GB2369591A - A tracheostoma filter

Info

Publication number: GB2369591A
Application number: GB0029499A
Authority: GB
Inventors: Ian David Worthington
Original assignee: Kapitex Healthcare Ltd
Current assignee: Kapitex Healthcare Ltd
Priority date: 2000-12-02
Filing date: 2000-12-02
Publication date: 2002-06-05
Anticipated expiration: 2020-12-02
Also published as: GB0029499D0; DE20119493U1; GB2369591B

Abstract

A tracheostoma filter comprises a substantially planar element 1 with at least one sealed edge 6. The sealed edge 6 may be heat sealed by fusion and may have a generally rounded profile. Preferably the filter element is hot press cut from a sheet of foam or fabric material e.g. cellular polymeric foam or woven and non-woven fabrics. A skin adhesive layer 3 may be provided along one or more of the edges to facilitate adhesion of the filter element to the subject's neck over the stoma. The adhesive layer may be positioned at the edge of the filter element and may be provided with a backing layer 4 that extends beyond the adhesive layer to provide a projecting portion 5 or a kiss-cut notch to facilitate its removal. Sealing the edge of the filter element eliminates stray loose fibres which reduces irritation of the wearer, increases durability and serves to ensure that the edges are no longer prone to the accumulation of dirt. The filter element is attached directly to the skin minimising additional components e.g. a frame or holder. The filter element may be supplied with double-sided adhesive tape.

Description

TRACHEOSTOMA FILTER AND METHOD OF MANUFACTURE THEREOF The application relates to a tracheostoma filter for filtering air that is to be breathed through a tracheostoma, for example for use by patients who have received a tracheostomy, for example as part of a laryngectomy. In particular, the invention relates to a simple self adhesive filter for use without any frame or mounting apparatus, and to a method of manufacture thereof.

Patients with a stoma in the trachea, for example following a laryngectomy or similar surgery, need to be provided with some sort of filter to cover the stoma for a number of reasons. First, a physical barrier is needed to prevent the ingress of foreign bodies for hygiene and like reasons. Second, a filter can have a partial barrier effect assisting in the maintenance of desirable conditions within the patient's airway (for example in relation to temperature and humidity), and similarly the filter can offer a degree of breathing resistance. The filter thus, at least in part, compensates for the loss of upper airway resistance in the part of the airway which now sits above the stoma, and in particular performs some of the natural functions of the nose.

For certain applications, in particular in connection with assisting laryngectomy patients to speak, quite sophisticated and complex filter designs have been proposed. However, in many instances, a simple form of filter remains effective, adequate and cheap. Such a filter generally takes the form of a generally planar open-cell reticulated foam, such as a polyurethane foam, which is cut to a suitable size to cover the tracheostoma and is then fixed over the stoma. Typically, the filter maybe provided with a self adhesive mechanism, such as a strip of skin-adhesive tape along an edge or edges

thereof. Simple filters of this type can readily and rapidly be cut from a larger sheet of foam material or woven or non-woven fabric, to offer a cheap, massproducable filter which is effective for many purposes.

This simple filter is not without its drawbacks. In particular, the cut edges of the foam or fabric material can be prone to fraying, to causing irritation on the neck of the subject, and to accumulation of dirt. It is an object of the present invention to provide a simple tracheostoma filter, and a method of manufacture thereof, which mitigates some or all of these disadvantages.

Thus according to the invention a tracheostoma filter comprises a substantially planar filter element for example of foam or fabric material wherein at least one edge of the filter element is sealed. Preferably, the at least one edge is heat sealed, preferably by fusion of the material of the filter element. Preferably, the at least one sealed has a generally rounded profile. Either or both of these effects can be achieved if the edge is hot cut, and in particular if the edge is hot press cut.

Sealing the edge of the filter element in this way offers a number of advantages. The elimination of stray cut fibres reduces the degree of irritation which might be experienced by a sensitive wearer. Similarly, the elimination of stray loose fibres at the edges is likely to increase durability and restrict fraying in use, and further serves to ensure that the edges no longer constitute an area prone to the accumulation of dirt to the detriment of hygiene.

It is the intention that the filter is as simple as possible, and that additional components are kept to a minimum. In particular, as has been noted, the edge or edges are preferably heat sealed by fusion of the foam or fabric material of the filter element at the edges to be sealed rather than by provision of any

secondary edging material. This latter alternative, whilst within the scope of the invention in its, broadest concept, is unlikely to be preferred. The filter element is not generally mounted in a frame, holder or like component, but is attached directly to the skin of the subject by suitable adhesive.

Reference herein to a foam or fabric material for the filter element is to any foam or fabric material suitable for performing the filtering function. Suitable materials include open cellular foams, in particular open cellular polymeric foam; woven and non-woven fabrics, and fabric-like polymeric layers. It has been noted that the edges of the filter element are preferably heat sealed by fusion, and accordingly the foam or fabric material is preferably a fusible polymeric material. The filter element may comprise one or more, similar or dissimilar, such layers, and may optionally include further layers primarily for other purposes. However for simplicity of fabrication, a single layer of foam or fabric material is preferred.

Preferably, an open-cell foam is used. Any suitable reticulated open-cell foam material may be used for the filter element. Particularly preferred materials will be those which are readily fusible to seal the edges in the preferred manner described. Preferably, the filter element comprises one or more, similar or dissimilar, polymeric open-cell foam layers, optionally including further fabric layers for other purposes. For the majority of applications, for simplicity, a single layer of polymeric open-cell foam material, preferably suitably fusible as above described, is likely to be preferred. Polyurethane foams and especially polyester based polyurethane foams are particularly preferred, but other materials will readily suggest themselves to those skilled in the art.

In a preferred embodiment, the filter element is provided with a skin-adhesive strip, preferably along one or more edges thereof, to facilitate adhesion of the filter element to the subject's neck over the stoma. Alternatively, the filter element may be supplied in a kit of parts together with suitable double-sided adhesive tape or other material suitable to releasably adhere the filter element to the skin of the subject over the stoma.

Such an adhesive strip is preferably provided along a generally straight edge or edges of the filter element. The adhesive strip is preferably provided along a single edge of the filter element, but may be provided along more than one edge thereof. Preferably in this case at least all of the remaining edges are sealed in the manner above described.

The adhesive strip maybe bonded to the surface of the filter element by any suitable means such as permanent adhesive bonding. Preferably, the adhesive strip is additionally or alternatively thermally sealed to the filter element, in particular at the edge thereof.

The filter element is suitably sized to fit over the stoma of the subject, and may be of any suitable shape. For example, the filter element may be generally square, rectangular, circular, elliptical, semi-circular etc.

Particularly convenient shapes are those with at least one straight edge to which an adhesive strip may be applied as above.

Where the shape of the filter element is such as to incorporate comers, these are preferably rounded for analogous reasons to those given for the rounding of the edge profile.

The adhesive layer is preferably provided with a removable backing layer, to facilitate handling during fabrication and transport. Preferably, the adhesive layer is positioned at an edge of the filter element, and particularly preferably is heat-sealed to the filter element at the said edge, and the backing layer extends away from the edge beyond the adhesive layer to provide a projecting portion facilitating its removal. Additionally or alternatively, the backing layer may be provided with a kiss-cut notch or other means to facilitate its removal.

In accordance with the further aspect of the invention there is provided a method of manufacture of a tracheostoma filter comprising cutting a substantially planar filter element from a supply of substantially planar filter material, for example comprising a foam or fabric material, and in particular an open cell reticulated foam material, wherein at least one edge thereof is hot cut at sufficient temperature to seal the said edge by fusion of the material of the filter element. Preferably, the filter element is press-cut from the material supplied, the applicable cutting elements being at sufficient temperature to seal the edges to be sealed by fusion of the material as described.

Preferably, the method further comprises the attachment of an adhesive strip along one or more edges of the filter element, and in particular the prior attachment of an adhesive strip before cutting of the foam filter element.

Using the hot press cutting technique enables the adhesive strip to be sealed effectively to the filter element by heat sealing, at least at the edge thereof.

The invention will now be described by way of example only with reference to Figures 1 and 2 of the accompanying drawings.

Figures la illustrates an embodiment of the invention in plan view, and Figure 1 b a cross section of Figure la across line A-A.

In the figures, the filter element 1 of open cell reticulated polyurethane foam is illustrated. Preferably, a hydrophilic polyester based polyurethane such as Hydrolox is used. Hydrolat ? a reticulated fully open-pored foam, constructed from a flexible polyester based polyurethane and having the following physical characteristics: 80 to 110 pores per linear inch (per linear 25.4 mm); density of 30 to 37 kg per cubic metre.

The filter element is generally square in plan view. Along an upper straight edge 2 of the filter element an adhesive layer 3 is provided. The adhesive layer 3 is protected by backing tape 4 which extends beyond the adhesive layer across a projecting region 5 where no adhesive is present. This facilitates its removal for attachment of the filter to the neck of a subject over the stoma.

The free cut edges 6 are sealed and rounded in accordance with the invention.

This is achieved by hot press cutting from a sheet of the polyurethane foam, with the cutting rate and the temperature of the cutting tool together being maintained at a level which ensures fusion sealing of the cut edges of the polyurethane foam. The free comers 7 are also rounded.

Figures 2a-c illustrate alternative embodiments of filter, which might be preferred in certain applications, with like reference numerals used to identify like components. Figures 2a and 2b illustrate alternative shapes of filter element 1 (respectively semi-circular and circular). Again an adhesive layer 3 is provided, with a backing tape layer 4 which overlaps 5 to facilitate removal. Figure 2c is a generally rectangular filter element, again with rounded comers 7. In this instance however, the backing layer 4 is provided with a kiss-cut 8 to facilitate its removal.

Other suitable shapes of filter will readily suggest themselves to those skilled in the art.

Claims

CLAIMS 1. A tracheostoma filter comprising a substantially planar filter element wherein at least one edge of the filter element is sealed.
2. A tracheostoma filter in accordance with claim 1 wherein the at least one edge is heat sealed by fusion of the material of the filter element.
3. A tracheostoma filter in accordance with claim 1 or claim 2 wherein the at least one sealed edge has a generally rounded profile.
4. A tracheostoma filter in accordance with claim 2 or claim 3 wherein the at least one edge is hot press cut.
5. A tracheostoma filter in accordance with any preceding claim wherein the filter element is of foam or fabric material.
6. A tracheostoma filter in accordance with claim 5 wherein the filter element is of material selected from open cellular foams, in particular open cellular polymeric foam; woven and non-woven fabrics, and fabric-like polymeric layers.
7. A tracheostoma filter in accordance with claim 6 wherein the foam and/ or fabric material is a fusible polymeric material.
8. A tracheostoma filter in accordance with claim 6 or claim 7 wherein the filter element comprises a reticulated open-cell foam material.
9. A tracheostoma filter in accordance with claim 8 wherein the filter element comprises a polyurethane foam and especially a polyester based polyurethane foam.
10. A tracheostoma filter in accordance with any preceding claim wherein the filter element is provided with a skin-adhesive strip along one or more edges thereof, to facilitate adhesion of the filter element to the subject's neck over the stoma.
11. A tracheostoma filter in accordance with claim 10 wherein the adhesive layer is provided with a removable backing layer, to facilitate handling during fabrication and transport.
12. A tracheostoma filter in accordance with claim 11 wherein the adhesive layer is positioned at an edge of the filter element, and the backing layer extends away from the edge beyond the adhesive layer to provide a projecting portion facilitating its removal.
13. A tracheostoma filter in accordance with claim 11 or claim 12 wherein the backing layer is be provided with a kiss-cut notch to facilitate its removal.
14. A kit of parts for a tracheostoma filter comprising a filter element in accordance with any preceding claim supplied with suitable double sided adhesive tape or other material suitable to releasably adhere the filter element to the skin of the subject over the stoma.
15. A method of manufacture of a tracheostoma filter comprising cutting a substantially planar filter element from a supply of substantially planar

filter material, wherein at least one edge thereof is hot cut at sufficient temperature to seal the said edge by fusion of the material of the filter element.
16. A method in accordance with one of claims 13 to 15 further comprising the attachment of an adhesive strip along one or more edges of the filter element, and in particular the prior attachment of an adhesive strip before cutting of the foam filter element.

16. A method in accordance with claim wherein the filter element is press cut from the material supplied, the applicable cutting elements being at sufficient temperature to seal the edges to be sealed by fusion of the material as described.

17. A method in accordance with claim wherein the filter material comprises an open cell reticulated foam material.

18. A method in accordance with claim further comprising the attachment of an adhesive strip along one or more edges of the filter element, and in particular the prior attachment of an adhesive strip before cutting of the foam filter element.

Amendments to the claims have been filed as follows

1. A tracheostoma filter comprising a substantially planar filter element consisting of a single layer of foam or fabric material at least one edge of which is heat sealed by fusion of the material of the filter element.

2. A tracheostoma filter in accordance with claim 1 wherein the at least one sealed edge has a generally rounded profile.

3. A tracheostoma filter in accordance with claim 2 wherein the at least one edge is hot press cut.

4. A tracheostoma filter in accordance with any preceding claim wherein the filter element is of material selected from open cellular foams, in particular open cellular polymeric foam; woven and non-woven fabrics, and fabric-like polymeric layers.

5. A tracheostoma filter in accordance with any preceding claim wherein the foam and/or fabric material is a fusible polymeric material.

6. A tracheostoma filter in accordance with claim 4 or claim 5 wherein the filter element comprises a reticulated open-cell foam material.

7. A tracheostoma filter in accordance with claim 6 wherein the filter element comprises a polyurethane foam and especially a polyester based polyurethane foam.

8. A tracheostoma filter in accordance with any preceding claim wherein the filter element is provided with a skin-adhesive strip along one or more edges thereof, to facilitate adhesion of the filter element to the subject's neck over the stoma.

9. A tracheostoma filter in accordance with claim 8 wherein the adhesive layer is provided with a removable backing layer, to facilitate handling during fabrication and transport.

10. A tracheostoma filter in accordance with claim 9 wherein the adhesive layer is positioned at an edge of the filter element, and the backing layer extends away from the edge beyond the adhesive layer to provide a projecting portion facilitating its removal.

11. A tracheostoma filter in accordance with claim 9 or claim 10 wherein the backing layer is be provided with a kiss-cut notch to facilitate its removal.

12. A kit of parts for a tracheostoma filter comprising a filter element in accordance with any preceding claim supplied with suitable double sided adhesive tape or other material suitable to releasably adhere the filter element to the skin of the subject over the stoma.

13. A method of manufacture of a tracheostoma filter comprising cutting a substantially planar filter element from a supply of substantially planar filter material consisting of a single layer of foam or fabric material, wherein at least one edge thereof is hot cut at sufficient temperature to seal the said edge by fusion of the material of the filter element.

14. A method in accordance with claim 13 wherein the filter element is press-cut from the material supplied, the applicable cutting elements being at sufficient temperature to seal the edges to be sealed by fusion of the material as described.

15. A method in accordance with claim 13 or 14 wherein the filter material comprises an open cell reticulated foam material.