Abstract:
A plaster for attaching a trachestoma valve in connection with a traceostoma on a person&#39;s neck. The plaster comprises a socket and an annular flange, communicating with a central opening of the flange which is connected with a single-coated adhesive tape, which extends radially beyond the edge of the flange. The connection includes a first annular joint at or inwardly of the outer periphery of the flange, and a second annular joint located between the outer periphery of the flange and the inner periphery of the flange spaced radially from the first annular joint. A protecting liner covers the adhesive on the tape.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a plaster for attaching a tracheostoma valve or the like to a persons neck in connection with a tracheostoma, comprising a socket open at both ends thereof for mounting the valve or the like to the plaster, an annular flange integrally connected with a proximal end of the socket at an inner periphery of the flange concentrically surrounding said end, the flange being angled or curved towards the wall of the socket, an annular tape attached to a proximal side of the flange and covering said proximal side, and an adhesive on a proximal side of said tape. 
     A plaster of this kind is flangelosed in EP-A1-0 078 685. 
     BACKGROUND OF THE INVENTION 
     Due to disease, often cancer, it may be necessary to remove the larynx by surgery (laryngectomy). By removal of the larynx several important functions are lost. The epiglottis and the closing function thereof is lost, and therefore an opening into trachea, a tracheostoma, has to be provided in the neck of the patient in order to create a direct connection with trachea. The tracheostoma is sometimes lowered (depressed) in relation to the surface of the patient&#39;s neck around the stoma and may have an irregular form because it is often necessary to remove tissue around the stoma. 
     The vocal cords and thus the ability to speak are also lost. In order to re-create a kind of speech a fistula is formed by surgery between oesophagus and trachea, and a voice prosthesis which is a one-way valve (U.S. Pat. No. 5,578,083) is placed therein. By means of a finger or a tracheostoma valve the tracheostoma can be closed off in order to prevent air from going out through the tracheostoma, air being pressed from the lungs to oesophagus through the voice prosthesis whereby the mucosa of oesophagus is starting to vibrate and it is possible to speak (U.S. Pat. No. 4,325,366). 
     It is also known to connect some kind of heat and moisture exchanger to the tracheostoma. Therefore, the expression “tracheostoma valve” as used in the present description is meant to include any other appliance connected to the tracheostoma. 
     Irrespectively of the kind of appliance that is connected to the tracheostoma, the most common way to accomplish said connection is by means of an annular flange flange attached to the patient&#39;s neck by means of an adhesive. However, there is on the market also a disposable plaster for attaching tracheostoma valves to the neck, and this plaster is formed of a single-coated tape fixed to a flange. The flange forms a socket and a plane flange fixed to the tape. The plaster has a generally plane surface to be attached to the skin surrounding the tracheostoma. This type of plaster causes problems regarding tension and incomplete contact with the skin close to the tracheostoma due to the fact that the stoma normally is lowered or depressed. 
     Further prior art means for attachment to a patient&#39;s neck in connection with a tracheostoma includes an annular flange and a socket integral with the flange and projecting from one side thereof at an angle to the axis of the socket. The tracheostoma valve is exchangeably received in the socket. The flange is made of plasticized PVC. A double-coated tape is attached to the flange on the other side thereof as means for attaching the flange against the skin surrounding the tracheostoma. The tape must not extend beyond the edge of the flange, as any exposed adhesive of the tape will attract dirt and dust discolouring the tape. The flange is to be reused. Thus, when the tape is to be replaced the patient first has to remove the double-coated tape from the flange, clean the flange with a solvent, let the flange dry, and then apply a new double-coated tape to the flange. This procedure is repeated at least once a day. 
     Though the products of the above type work well in many respects, there are still some problems. The known products are normally of a type to be re-used, which means that cumbersome cleaning by means of unhealthy solvents has to be effected. Often the patient is elderly and will find problems in performing these steps. In order that the tape shall adhere to the flange this is made of plasticized poly-vinyl chloride (PVC). This plastic is known to cause health problems and accordingly should be avoided. The tape is fixed to the whole area of the flange, which means that it relatively easy may come loose from the skin due to the fact that a large force is concentrated to the tape edge adjacent the tracheostoma. When the tracheostoma valve is used during speaking and coughing or is to be removed, the socket is exposed to large axial forces, putting the tape edge adjacent the socket under tension. As the flange is relatively small and the adhesive tape does not extend beyond it or at least not far beyond it, it is difficult to have sufficient adherence on patients having a large and irregular tracheostoma. The flange is inclined but since the tracheostoma often is lowered or depressed and the skin around the tracheostoma often is relatively plane the inclined flange will cause surrounding skin to adapt an unnatural form and in this way creates tensions in the tissues and thus flangeomfort to the patient. Furthermore, there is an increased risk that the plaster will more easily loosen from the patient&#39;s neck. 
     SUMMARY OF THE INVENTION 
     One object of the present invention is to provide a plaster of the kind referred to herein having attachment means that follows the depressed or lowered tracheostoma and the relatively plane surrounding skin for optimal adherence without causing any tension or discomfort to the patient. The attachment means should also be able to take up much larger forces and not come loose as easily as prior art products. Furthermore, the plaster should be less cumbersome to handle for the patient. 
     The above objects are attained according to the present invention by a plaster of the kind referred to which according to claim  1  is characterized in that the annular tape is a single coated adhesive tape attached to the flange by a first annular joint at or inwardly of the outer periphery of the flange and extends radially beyond the edge of the flange, and that the annular tape is attached to the flange by a second annular joint located between said outer periphery of the flange and said inner periphery of the flange spaced radially from said first annular joint, a protecting liner covering the adhesive on the tape. 
     A further object of the present invention is to provide a plaster for connection to the tracheostoma which is of disposable type so that there is no need for the patient to perform the cumbersome and health jeopardising steps of changing the double-coated adhesive tape, which by many patients is felt as a major problem. 
     A still further object is to provide a plaster which can cover also big and irregular tracheostomas. 
     Another object is to make the plaster of biocompatible and environment friendly materials, reducing risks for both patient and environment. 
     Further advantageous features of the invention are defined in the dependent claims. 
     In order to adapt the plaster to different types of tracheostomas the design of the adhesive tape may be adjusted as to form and size without the flange being a limiting element as is the case with prior art devices. 
     Further objects and advantages of the present invention will be obvious to a person skilled in the art when reading the following detailed description of illustrative embodiments of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the accompanying drawings, 
         FIG. 1  is a perspective view of a plaster for tracheostoma valves or the like according to a first embodiment of the invention as seen from the distal side thereof, 
         FIG. 2  is a plan view of the distal side of the plaster of  FIG. 1 , 
         FIG. 3  is a cross sectional view of the plaster of  FIGS. 1 and 2 , taken along line A-A of  FIG. 2 , 
         FIG. 4  is a plan view of a second embodiment of a plaster for tracheostoma valves or the like as seen from the distal side, 
         FIG. 5  is a cross sectional view as in  FIG. 3  of the plaster of  FIG. 4 . 
         FIG. 6  is a perspective view as seen from the distal side of a plaster according to a third embodiment of the invention, 
         FIG. 7  is a perspective view of the plaster in  FIG. 6  as seen from the proximal side thereof, 
         FIG. 8  is a perspective view of a fourth embodiment of the plaster of the invention as seen from the distal side thereof, 
         FIG. 9  is a plan view of a fifth embodiment of the plaster of the invention as seen from the distal side thereof, 
         FIG. 10  is a perspective view of the plaster in  FIG. 9  as seen from the distal side thereof, and 
         FIG. 11  is a perspective view of the plaster in  FIG. 9  as seen from the proximal side thereof. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     The plaster according to the present invention comprises a first flange or central, annular flange  1  (hereinafter “flange  1 ”), which forms a central socket  2  and a second flange or flange  3  thereinafter “flange  3 ”) concentrically surrounding socket  2 . Thus, socket  2  forms a central opening of flange  1 . In the embodiments of  FIGS. 1 to 5 , flange  3  is inclined at an angle  4  in relation to the central axis  9  of socket  2 . The angle  4  may vary but is preferably between 30° and 80° and more preferably between 50° and 70° . Due to the angle  4  of flange  3  a base plane  11  perpendicular to axis  9  and including the area where socket  2  and flange  3  are joined, is placed at a distance  10  from a top plane  12  perpendicular to axis  9  and located at the highest or relatively plane level of the plaster. Distance  10  between base plane  11  and top plane  12  normally is between 2and 15mm, and preferably between 3and 10mm. 
     The annular flange  1  is preferably made of low density polyethylene, which is a very biocompatible and soft polymer. The flange may also be made of other relatively soft polymers. 
     A single-coated adhesive tape  6  which has adhesive on one side only, as distinct from a double-coated adhesive tape which has adhesive on both sides thereof is attached to flange  3 . Tape  6  is preferably of a medical grade and extends beyond the edge of flange  3  of the annular flange  1  and has a generally plane form outside the flange. Tape  6  extends along flange  3  of flange  1  close to the edge of socket  2 , and at the outer periphery it forms two diametrically opposite enlargements  6 A which increase the surface to be attached to the skin around the tracheostoma by the adhesive tape. In the manufacture of the plaster the adhesive of tape  6  is covered by some kind of liner or backing  8  which should be removed before the tape is attached to the patient. Tape  6  forms a flap  7 , which is not covered by adhesive. This flap  7  facilitates removal of liner  8  from tape  6 . Tape  6  is preferably made of polyethylene but may also be made of other biocompatible materials. 
     Flange  1  and the adhesive tape  6  are fixed to each other by means of two annular welds  5 A and  5 B extending around flange  3  of flange  1  concentrically with socket  2 . One weld  5 A is placed adjacent the outer edge of flange  1  and the other weld  5 B at a relatively short radial distance inwardly of the edge radially spaced from socket  2 . Preferably the radial distance between the innermost weld  5 B and the inside surface of socket  2  is at least 2 mm. The welds may be formed by means of heat or ultrasonic welding e.g. by using impulse welding or a continuously heated welding head. As there is a distance between socket  2  and welds  5 A,  5 B axial forces on socket  2  will not put the tape edge under large tension, which is the case in the prior art products where there is no such distance. 
     The embodiment of  FIGS. 4 and 5  differs from the embodiment of  FIGS. 1 to 3  regarding the form of the flange  3 ′ of the flange  1 ′. Flange  3 ′ has a curvature as seen in cross section. The curvature of flange  3 ′ may vary. In the same way as in the previous embodiment by the curvature of flange  3 ′ the base plane  11  is placed at a distance  10  from the top plane  12 . Said distance  10  between the two planes  11 ,  12  is normally between 2 and 15 mm, and most preferably between 3 and 10 mm. 
     In the embodiments shown flange  3  of flange  1  of  FIGS. 1 to 3  is generally conical while flange  3 ′ of flange  1 ′ of  FIGS. 4 and 5  has a curvature. The person skilled in the art realises that the flange may have any curvature as long as it has a general inclination in relation to the central axis  9  of socket  2 . As stated above the purpose of the general inclination is to adapt the plaster to the form of the tracheostoma which normally is lowered or depressed in relation to the surrounding skin. 
     Conventional paper liners cannot be used with plasters having a flange  1 ,  1 ′ with an inclined or curved flange  3 ,  3 ′. Liner  8  most follow the form of the plaster, other-wise the adhesive will dry at areas with no contact between plaster and liner. Thus, it should be possible to form the liner  8  so as to bring the shape thereof into agreement with the shape of the adhesive tape  6 , either by cold forming or by thermo forming. The forming of the liner  8  and tape  6  may be done by means of a stamp or by vacuum forming, or blow moulding before, during, or after the fixation of the tape  6  to the flange  1 ,  1 ′. According to a presently used method liner  8  and tape  6  are formed by cold forming before securing tape  6  to flange  1 ,  1 ′. However, it is always necessary to adapt the form of liner  8  to the form of the plaster. 
     When the plaster for the tracheostoma valve is to be applied, liner  8  is first removed. Tape  6  is then applied to the skin surrounding the stoma. The plaster is placed in a position where the central socket  2  is aligned with the stoma. Then, the tracheostoma valve is attached to the socket  2 . It is the lower side of the plaster as seen in  FIGS. 2 and 5  which is to be applied against the skin of the patient. When the plaster is to be replaced the above procedure is reversed, i.e. first the valve is removed, then the plaster, including the annular flange  1 , is removed and discarded. Finally a new plaster is applied as stated above. Thus, the plaster is not to be re-used, avoiding the previous problems with cleaning of the flange. 
     The shape of the tape  6  can be varied in many ways. In  FIGS. 6 and 7  the tape and the liner are circular and are substantially congruent. There are no enlargements as those shown in  FIGS. 1 ,  2  and  4 . Liner  8  forms a flap  13  which projects from flap  7  on tape  6 . The tape and the liner can easily be gripped at the flaps when it is desired to remove the liner from the adhesive surface of the tape. 
     In  FIG. 8  tape  6  and liner  8  are oval. Flap  7  (and flap  13 ) are located at one short side but can as well be located at one long side of tape  6  and liner  8 , respectively, or anywhere on the periphery of the tape and the liner. 
       FIGS. 9 to 11  show a still further shape of tape  6  and liner  8 . The shape is basely a rectangular shape with enlargements  6 A at two opposite sides. 
     The person skilled in the art realizes that the different parts may be adapted to the actual patient. Thus, the thickness and material of the adhesive tape may vary, e.g. due to the sensitivity of the patient&#39;s skin or the like. The extension of the tape outside the flange may also vary. Also the size and thickness of the flange may be varied.