Wound dressing

Abstract

This invention relates to a packaged sterile wound dressing comprising a dressing saturated with a pain relieving composition, a method of providing pain relief due to a wound of a subject using said dressing, and a method of manufacturing the packaged sterile wound dressing.

Claims

1. A packaged wound dressing comprising a dressing saturated with a pain relieving composition, wherein: the wound dressing is contained within a sealed sterile packaging; the wound dressing is folded into a compact form within the sterile packaging; the sterile packaging is a tear-open sachet; the wound dressing provides a predetermined therapeutic amount of said pain relieving composition; the pain relieving composition comprises at least one anaesthetic agent, an antiseptic agent, and a hydrophilic or hydroalcoholic gelling agent; the pain relieving composition is in the form of a liquid that sets as a sticky viscous gel when exposed to a wound; the dressing is removable from the wound; the dressing has an open pore structure or is open weave; and the dressing when unfolded is anywhere between 50 and 200 mm wide and 55 and 300 mm long.

2. The packaged wound dressing of claim 1, wherein the dressing has one or more of the following properties selected from the group consisting of: the dressing is adapted to stem wound bleeding; the dressing is adapted to help seal the wound; the dressing is adapted to protect the wound from infection; the dressing is adapted to ease pain; the dressing is adapted to promote healing of the wound; the dressing is adapted to promote granulation and epithelialisation of the wound; the dressing is adapted to prevent further trauma to the wound; the dressing is adapted to debride the wound; and, the dressing is adapted to obscure the wound from view and therefore lessen psychological stress.

3. The packaged wound dressing of claim 1, wherein the pain relieving composition comprises about 1 to 20 g per litre of at least one type of gum or cellulosic preparation, a polyhydric alcohol in combination with a cellulosic preparation, or about 5 mg/mL hydroxy cellulose in combination with about 100 mg/mL non-crystallising liquid sorbitol (70%).

4. The packaged wound dressing of claim 1, wherein the at least one anaesthetic agent has a rapid onset of action and/or a long duration of action.

5. The packaged wound dressing of claim 4, wherein the at least one anaesthetic agent is selected from the group consisting of lignocaine, chloroprocaine, mepivacaine, bupivacaine, articaine, etidocaine, levobupivacaine, amethocaine/tetracaine, prilocaine, benzocaine, ropivacaine, cocaine, oxyprocaine, hexylcaine, dibucaine, piperocaine and procaine.

6. The packaged wound dressing of claim 1, wherein the composition further comprises a vasoconstrictor.

7. The packaged wound dressing of claim 1, wherein the composition further comprises a colourant such that application of the composition to the wound can be easily assessed by eye.

8. The packaged wound dressing of claim 1, wherein the pain relieving composition comprises lignocaine, bupivacaine, adrenaline, cetrimide, 2-ethyl hydroxycellulose, sodium metabisulfite, liquid sorbitol (70%), buffer, and, optionally, colourant.

9. The packaged wound dressing of claim 1, wherein the pain relieving composition comprises amethocaine/tetracaine, adrenaline, cetrimide, 2-ethyl hydroxycellulose, sodium metabisulfite, liquid sorbitol (70%), buffer, and, optionally, colourant.

10. The packaged wound dressing of claim 1, wherein the pain relieving composition comprises: about 100 mg/mL non-crystallising liquid sorbitol (70%); about 50.0 mg/mL lignocaine HCl; about 5.0 mg/mL bupivacaine HCl; about 1.5 mg/mL sodium metabisulfite; about 5.0 mg/mL cetrimide; about 45.0 μg/mL adrenaline tartrate; about 5.0 mg/mL hydroxy cellulose; and optionally colourant.

11. The packaged wound dressing of claim 1, wherein the pain relieving composition comprises: about 100 mg/mL non-crystallising liquid sorbitol (70%); about 40.0 mg/mL lignocaine HCl; about 1.5 mg/mL sodium metabisulfite; about 5.0 mg/mL cetrimide; about 36.0 μg/mL adrenaline tartrate; about 5.0 mg/mL hydroxy cellulose; and optionally colourant.

12. The packaged wound dressing of claim 1, wherein the pain relieving composition comprises: about 100.0 mg/mL sorbitol liquid 70% non-crystallising; about 50.0 mg/mL (5%) tetracaine HCl; about 1.5 mg/mL sodium metabisulfite; about 5.0 mg/mL cetrimide; about 45.0 μg/mL adrenaline tartrate; about 5.0 mg/mL hydroxy cellulose; and optionally colourant.

Description

BRIEF DESCRIPTION OF FIGURES

(1) FIG. 1 is picture of a dressing of a sterile wound dressing according to an embodiment of the present invention;

(2) FIG. 2 are pictures of various sized sachets containing the dressing shown in FIG. 1;

(3) FIG. 3 is a flow chart showing steps in the manufacture of the sterile wound dressing; and

(4) FIG. 4 is a photograph showing application of the dressing to a forearm of a person.

DESCRIPTION OF PREFERRED EMBODIMENTS

Example 1—Formulation of a Pain Relieving Composition for Wounds Having a Long Duration of Action

(5) This Example describes the preparation of a particularly preferred topical analgesic pain relieving composition. The composition is in the form of a gel that provides a prolonged analgesic effect. The composition has the following formulation:

(6) TABLE-US-00001 Purified water Sorbitol Liquid 100.0 mg/mL 70% Non-Crystallising Lignocaine HCl 50.0 mg/mL (5%) Bupivacaine HCl 5.0 mg/mL (0.5%) Sodium Metabisulfite 1.5 mg/mL Cetrimide 5.0 mg/mL Adrenaline Tartrate 45.0 μg/mL Hydroxy Cellulose 5.0 mg/mL Purified water to 1 mL Optional: Food Dye (e.g. brilliant blue) Quantity to suit (q.s.)

(7) The composition is prepared by combining/blending the above ingredients to achieve the required consistency.

(8) If desired, the composition can further comprise an anti-inflammatory agent (e.g. isoflupredone acetate or meloxicam 0.1%, 1 mg/ml), and/or an insecticide/insect repellent such as diazinon, spinosad or cyromazine (at about 1 mg/mL), and/or a skin penetrating enhancer, and/or a bittering agent.

(9) If desired, lignocaine can be swapped out and tetracaine swapped in at about 1-10%, but preferably about 5% (50 mg/mL).

Example 2—Formulation of a Pain Relieving Composition for Wounds

(10) This Example describes the preparation of another preferred pain relieving composition. The composition is in most respects the same as the composition of Example 1, except that it excludes bupivacaine. The composition has the following formulation:

(11) TABLE-US-00002 Purified water Sorbitol Liquid 100.0 mg/mL 70% Non-Crystallising Lignocaine HCl 40.0 mg/mL (4%) Sodium Metabisulfite 1.5 mg/mL Cetrimide 5.0 mg/mL Adrenaline Tartrate 36.0 μg/mL (1:2000) Hydroxy Cellulose q.s. Purified water to 1 mL Optionally: Food Dye (e.g. blue) q.s.

(12) The composition is prepared by combining/blending the above ingredients to achieve the required consistency.

(13) If desired, the composition can further comprise an insecticide/insect repellent such as cyromazine or spinosad (at about 1 mg/mL), an NSAID (e.g. meloxicam 0.1%, 1 mg/ml), and/or a skin penetrating enhancer.

(14) If desired, lignocaine can be swapped out and tetracaine swapped in at about 1-10%, but preferably about 5% (50 mg/mL).

Example 3—Formulation of a Topical Anaesthetic Creme Having a Long Duration of Action

(15) This Example describes the preparation of another topical pain relieving composition in the form of a creme. The composition has the following formulation:

(16) TABLE-US-00003 Cetyl Alcohol 78.00 mg/mL Paraffin Wax 135.00 mg/mL Glycerol 75.00 mg/mL Lauryl Sulfate 10.00 mg/mL Lignocaine HCl 50.00 mg/mL Bupivacaine HCl 5.00 mg/mL Sodium Metabisulfite 1.50 mg/mL Cetrimide 5.00 mg/mL Hydrochloric Acid 25% q.s. Adrenaline Acid Tartare 0.045 mg/mL Purified Water to 1 mL

(17) The composition is prepared by combining the above ingredients to achieve the required consistency as required. The composition is in the form of a “sticky” creme.

(18) If desired, the composition can further comprise an anti-inflammatory agent (e.g. meloxicam 0.1%, 1 mg/ml), and/or an insecticide/insect repellent, and/or a skin penetrating enhancer, and/or a bittering agent.

(19) If desired, lignocaine can be swapped out and tetracaine swapped in at about 1-10%, but preferably about 5% (50 mg/mL).

Example 4—Formulation of a Topical Anaesthetic Gel Having a Long Duration of Action

(20) This example describes the preparation of another topical anaesthetic composition having a gum base. The composition has the following formulation:

(21) TABLE-US-00004 Xanthum Gum 10.00 mg/mL Gum Arabic 1.00 mg/mL Sorbitol Liquid 100.00 mg/mL Lignocaine HCl 50.00 mg/mL Bupivacaine HCl 5.00 mg/mL Sodium Metabisulfite 1.50 mg/mL Cetrimide 5.00 mg/mL Hydrochloric Acid 25% q.s. Adrenaline Acid Tartare 0.045 mg/mL Purified Water to 1 mL Optional: Dye q.s.

(22) The composition is prepared by combining the above ingredients to achieve the required consistency. The composition is in the form of a “sticky” gel.

(23) If desired, the composition can further comprise an anti-inflammatory agent (e.g. meloxicam 0.1%, 1 mg/ml), and/or an insecticide/insect repellent, and/or a skin penetrating enhancer, and/or a bittering agent.

(24) If desired, lignocaine can be swapped out and tetracaine swapped in at about 1-10%, but preferably about 5% (50 mg/mL).

Example 5—Formulation of a Topical Anaesthetic Gel Having a Long Duration of Action

(25) This Example describes the preparation of another topical anaesthetic composition having a polyacrylic acid base. The composition has the following formulation:

(26) TABLE-US-00005 Polyacrylic Acid 10.00 mg/mL Sodium Hydroxide q.s. Polyhydrogenated Castor Oil 10.00 mg/mL Sorbitol Liquid 100.00 mg/mL Lignocaine HCl 50.00 mg/mL Bupivacaine HCl 5.00 mg/mL Sodium Metabisulfite 1.50 mg/mL Cetrimide 5.00 mg/mL Hydrochloric Acid 25% q.s. Adrenaline Acid Tartare 0.045 mg/mL Purified Water to 1 mL Optional: Dye q.s.

(27) The composition is prepared by combining the above ingredients to achieve the required consistency. The composition is in the form of a “sticky” gel.

(28) If desired, the composition can further comprise an anti-inflammatory agent (e.g. meloxicam 0.1%, 1 mg/ml), and/or an insecticide/insect repellent, and/or a skin penetrating enhancer, and/or a bittering agent.

(29) If desired, lignocaine can be swapped out and tetracaine swapped in at about 1-10%, but preferably about 5% (50 mg/mL).

Example 6—Formulation of a Topical Anaesthetic Gel Having an Insecticide and a Skin Penetrating Enhancer

(30) This Example describes the preparation of another topical anaesthetic composition in the form of a spray-on gel having an insecticide (spinosad) as well as a skin penetrating enhancer (propylene glycol). The composition has the following formulation:

(31) TABLE-US-00006 Cellulose 5.00 mg/mL Spinosad 1.25 mg/mL Propylene Glycol 100.00 mg/mL Sorbitol Liquid 50.00 mg/mL Lignocaine HCl 50.00 mg/mL Bupivacaine HCl 5.00 mg/mL Sodium Metabisulfite 1.50 mg/mL Cetrimide 5.00 mg/mL Hydrochloric Acid 25% q.s. Adrenaline Acid Tartare 0.045 mg/mL Purified Water to 1 mL Optional: Dye q.s.

(32) The composition is prepared by combining the above ingredients to achieve the required consistency. The composition is in the form of a “sticky” gel”.

(33) If desired, the composition can further comprise an anti-inflammatory agent (e.g. meloxicam 0.1%, 1 mg/ml), and/or a bittering agent.

(34) If desired, lignocaine can be swapped out and tetracaine swapped in at about 1-10%, but preferably about 5% (50 mg/mL).

Example 7—Formulation of a Pain Relieving Composition for Wounds

(35) This Example describes the preparation of another preferred pain relieving composition. The composition is in most respects the same as the composition of Example 2, except that it has tetracaine as both a rapid onset and long duration anaesthetic agent. The composition has the following formulation:

(36) TABLE-US-00007 Purified water Sorbitol Liquid 100.0 mg/mL 70% Non-Crystallising Tetracaine HCl 50.0 mg/mL (5%) Sodium Metabisulfite 1.5 mg/mL Cetrimide 5.0 mg/mL Adrenaline Tartrate 45.0 μg/mL Hydroxy Cellulose 5.0 mg/mL Purified water to 1 mL Optional: Food Dye (e.g. brilliant blue) Quantity to suit (q.s.)

(37) The composition is prepared by combining/blending the above ingredients to achieve the required consistency.

(38) If desired, the composition can further comprise an insecticide/insect repellent such as cyromazine or spinosad (at about 1 mg/mL), an NSAID (e.g. meloxicam 0.1% 1 mg/ml), and/or a skin penetrating enhancer.

Example 8—Manufacture of a Sterile Wound Dressing

(39) This Example describes the preparation of a sterile wound dressing comprising sterile packaging (sachet) and a dressing saturated with the pain relieving composition of any one of Examples 1 to 7. FIG. 1 shows the dressing 1 saturated with the pain relieving composition. FIG. 2 shows suitable sachets 2a, 2b, 2c containing the dressing. FIG. 3 shows the basic manufacturing steps. FIG. 4 shows use of the saturated dressing 1 on an arm of a person.

(40) All manufacturing steps were completed at ambient temperature.

(41) A sachet was made from a six layer mixture of polyester, polyethylene and aluminium, its weight was approximately 120 gsm. It was chosen for its low linting properties.

(42) A dry 100% polyester dressing/wipe was inserted into the sachet. It was gamma irradiated, packaging layers were removed, and the sachet was then fed into a filling machine. The dry folded dressing/wipe in the open sachet was Gamma irradiated at a minimum of 25 kgy and a maximum of 45 kgy.

(43) The filling machine was an adapted form of a fill and seal machine that was generally used for manufacture of an individual towelette in a sachet.

(44) The pain relieving composition was prepared as described in Examples 1 to 7. The composition ingredients were blended together in a tank and then passed through two 0.2 micron filters, before being fed to the filling machine. Each filter was a 3M sterile life assure Pda filter capsule (0.2 micron).

(45) Trial batches were manufactured in a 50 litre tank. Commercial production will be carried out in an 800 litre tank.

(46) The filling machine filled each sachet with 7 ml of the pain relieving composition. Each sachet was then sealed and fed out of the machine for packing. Each sachet was sealed by heat at a temperature of approximately 140/150° C.

Example 9—Use of the Sterile Wound Dressing of Example 8 on a Wound

(47) This Example describes the use of the sterile wound dressing on a wound of a person's forearm. See FIGS. 1, 2 and 4.

(48) A sterile wound dressing sachet 2a, 2b, 2c was torn open and the dressing 1 removed. The dressing 1 was placed over a wound of forearm of a person, as shown in FIG. 4. The pain relieving composition (stained blue) which supersaturated the dressing 1 was absorbed by the wound and provided pain relief. After a suitable period of time, the dressing 1 was removed. The dressing 1 can also be used as a wipe to debride the wound or otherwise clean the wound or surrounding area.

(49) Advantages of the present invention as exemplified include that the wound dressing can be used to reduce or minimise pain in a large variety of situations in which anaesthetic agents are not currently used by virtue of being too impractical, dangerous, complex, costly, difficult to transport or apply.

(50) Quite frankly, the present inventor did not envisage that a dressing saturated with a pain relieving agent in a sterile sachet could work so well and so have so many potential applications.

(51) Advantages of the present invention as exemplified include: it was not envisaged that a saturated dressing in a satchel could work so well. it is an anaesthetising dressing. it is a vasoconstricting dressing. the active/agents are uniformly dispersed throughout the entire dressing. it provides a metered dose. the sachet is easily transportable and storable. the dressing can be used to cover large wounds. there is no pain relieving composition run-off the pain relieving composition is delivered exactly where required. there is no pain relieving composition wastage. lots of dressings can be wrapped around large areas, such as burn areas. the dressing is supersaturated with pain relieving agent. holding the dressing in a sachet with the pain relieving composition causes supersaturation. the dressing can provide a homogenous effect across the whole wound. the dressing can wrap around body parts. the dressing can cover large surface areas.

(52) Throughout this specification, unless in the context of usage an alternative interpretation is required, the term “comprise” (and variants thereof such as “comprising” and “comprised”) denotes the inclusion of a stated integer or integers but does not exclude the presence of another integer or other integers.

(53) Any reference to publications cited in this specification is not an admission that the disclosures constitute common general knowledge in Australia or in other countries.

(54) It will be appreciated by one of skill in the art that many changes can be made to the composition and uses exemplified above without departing from the broad ambit and scope of the invention.

(55) Preferred embodiments of the invention are described in the paragraphs below.

(56) 1. A wound dressing comprising a dressing saturated with a pain relieving composition:

(57) wherein the dressing is designed to be in direct contact with a wound; wherein the dressing is supersaturated with the pain relieving composition; wherein the dressing has an open pore structure or is open weave; wherein the dressing is anywhere between about 50 and 200 mm wide and about 50 and 300 mm long; wherein the dressing is made of 100% polyester; wherein the dressing has one or more of the following properties: it stems wound bleeding; it helps seal the wound; it protects the wound from infection; it eases pain; it promotes healing of the wound; it promotes granulation and epithelialisation of the wound; it prevents further trauma to the wound; it debrides the wound; and, it obscures the wound from view and therefore lessens psychological stress; wherein the wound dressing is extendible around a limb to cover a large surface area of the limb; and/or wherein the wound dressing is adapted to be used for an animal husbandry procedure.
2. The wound dressing of paragraph 1, wherein: the pain relieving composition is in the form of a liquid, ointment, gel, lotion, cream, crème, emulsion, paste, film or suspension; the pain relieving composition is in the form of a liquid that sets as a sticky viscous gel when exposed to the wound; the pain relieving composition comprises a hydrophilic or hydroalcoholic gelling agent; the pain relieving composition comprises about 1 to 20 g per litre of at least one type of gum or cellulosic preparation; the pain relieving composition comprises a polyhydric alcohol in combination with a cellulosic preparation; or the pain relieving composition comprises about 5 mg/mL hydroxy cellulose in combination with about 100 mg/mL non-crystallising liquid sorbitol (70%).
3. The wound dressing of paragraph 1 or paragraph 2, wherein the pain relieving composition comprises at least one anaesthetic agent having a rapid onset of action and/or a long duration of action.
4. The wound dressing of paragraph 3, wherein the at least one anaesthetic agent is lignocaine, chloroprocaine, mepivacaine, bupivacaine, articaine, etidocaine, levobupivacaine, tetracaine, prilocaine, benzocaine, ropivacaine, cocaine, oxyprocaine, hexylcaine, dibucaine, piperocaine or procaine, or pharmaceutically acceptable acids, bases and salts thereof.
5. The wound dressing of paragraph 4, wherein the at least one anaesthetic agent having a rapid onset of action is lignocaine, prilocaine, amethocaine/tetracaine or cocaine, and the at least one anaesthetic agent having a long duration of action is bupivacaine, ropivacaine, levo-bupivacaine or amethocaine/tetracaine.
6. The wound dressing of paragraph 4, wherein the at least one anaesthetic agent having both a rapid onset of action and long duration of action, is amethocaine/tetracaine.
7. The wound dressing of any one of paragraphs 1 to 6, wherein the composition comprises: a vasoconstrictor; or an antiseptic agent; or a colouring agent/colourant such that application of the composition to the wound can be easily assessed by eye; or about 100 mg/mL non-crystallising liquid sorbitol (70%); about 50.0 mg/mL lignocaine HCl; about 5.0 mg/mL bupivacaine HCl; about 1.5 mg/mL sodium metabisulfite; about 5.0 mg/mL cetrimide; about 45.0 μg/mL adrenaline tartrate; about 5.0 mg/mL hydroxy cellulose; and optionally dye; or about 100 mg/mL non-crystallising liquid sorbitol (70%); about 40.0 mg/mL lignocaine HCl; about 1.5 mg/mL sodium metabisulfite; about 5.0 mg/mL cetrimide; about 36.0 μg/mL adrenaline tartrate; about 5.0 mg/mL hydroxy cellulose; and optionally dye; or about 100.0 mg/mL purified water sorbitol liquid 70% non-crystallising; about 50.0 mg/mL (5%) tetracaine HCl; about 1.5 mg/mL sodium metabisulfite; about 5.0 mg/mL cetrimide; about 45.0 μg/mL adrenaline tartrate; about 5.0 mg/mL hydroxy cellulose; to 1 mL purified water; and optionally dye; or lignocaine, bupivacaine, adrenaline, cetrimide, 2-ethyl hydroxycellulose, sodium metabisulfite, liquid sorbitol (70%), buffer, and, optionally, dye; or amethocaine/tetracaine, adrenaline, cetrimide, 2-ethyl hydroxycellulose, sodium metabisulfite, liquid sorbitol (70%), buffer, and, optionally, dye.
8. The wound dressing of any one of paragraphs 1 to 7, wherein: (1) the wound dressing is contained within sterile packaging; (2) the wound dressing is contained within sterile packaging in the form of a tear-open sachet; (3) the wound dressing is contained within sterile packaging and the sterile packaging contains between about 4-10 ml of the pain relieving composition; or (4) the dressing is folded into a compact form within the sterile packaging of any one of (1) to (3).
9 A method of providing pain relief due to a wound of a subject, said method comprising the step of applying the wound dressing of any one of paragraphs 1 to 8 to the wound of the subject; or use of the wound dressing of any one of paragraphs 1 to 8 in the preparation of a medicament for providing pain relief due to a wound of a subject.
10. A method of manufacturing a sterile wound dressing according to any one of paragraphs 1 to 8, said method comprising the step of packaging a dressing saturated with a pain relieving composition in a sterile manner so as to produce a sterile wound dressing.