MXPA99002212A - Anti-harmful woven bandage of cellular acetate - Google Patents

Abstract

A single fabric with non-adherent characteristics is described which are suitable for use as a wound dressing, particularly as a burn dressing, the fabric comprises cellulose acetate fibers and a siloxane finish on the fibers, in a preferred embodiment, the bandage comprises cellulose acetate fibers, cellulose acetate fibers having an antibiotic incorporated in the resin of the fiber, and a siloxane finish in the fibers, it was discovered that the fabric of the invention is less adherent to burns than bandages made of cotton or having a nylon mesh around an absorbent pad, and it was also less adherent than a commercially available cellulose acetate bandage

Description

ANTIADHERENT WOUND BANDAGE OF CELLULOSE ACETATE FIELD OF THE INVENTION The invention relates to a non-stick cellulose acetate wound pad or bandage, and in particular to a non-stick pad of a cellulose acetate having a low level of siloxane terminating agent applied thereto. The pad has a use in the area of medical technology for application to wounds, particularly burns.

BACKGROUND OF THE INVENTION Various injuries, and particularly burns, require the application of a certain type of pad, gauze, cloth, bandage or similar coating (collectively referred to herein as "bandage") to protect the wound while it heals. Wounds, especially burns, sometimes have difficulty healing and are often prone to infection because natural protective skin barriers burst and recovery is slow. The most commonly used bandage material has been cotton, because it is inexpensive and easy to find. However, although those who have used cotton bandages are aware, they tend to fix it to the injured area, even when the surface of the area is covered with a lubricant such as Vaseline ("petrolatum") or a similar substance, or a medicine that contains lubricant. Advances in the medical field have resulted in some improvements in medical bandages, which are represented by the non-adherent bandages of the Johnson & Johnson 's ADAPTIC TM and the Curity brand, the sterile TELFA pads sold by Kendall - Futuro Company. It was discovered that the ADAPTIC ™ brand bandage of a cellulose acetate pad has been soaked in petrolatum or a similar substance to impart anti-stick properties. Although petrolatum reduces adhesion to a wound, its results of use on a pad are that it is greasy and dirty to handle compared to a pad without petrolatum. The TELFA bandage consists of a polyethylene terephthalate (PET) shell and a washed caustic cotton insert, the non-stick properties are imparted by the PET shell. Another bandage is disclosed in Chinese Patent No. CN 87 1 01823 A, published on August 31, 1988, to Tie Han et al. Said Chinese Patent discloses a "non-stick medicinal bandage" prepared by the use of flat cellulose acetate to make a spun and woven gauze, or a non-woven fabric having a weight of 50-80 g / m2. No additional training is provided as regards the treatment of the cellulose acetate material before, during or after the preparation of the bandage. The bandage did not contain a biostat He used a suggested biostat. U.S. Patents that describe the use of cellulosic materials and siloxane materials in wound dressing include: * No. 5,372,739 from B. Shriram, which describes fibers including cellulose acetate fibers, which have fatty acids of polyethylene glycol therein to reduce adhesion; * No. 4,984,570 to Langen et al., Which discloses a wound dressing having an absorbent cellulose acetate pad and a man-made hydrophobic fiber covering the covering pad which is in contact with the wound; * No. 4,546,027 to Holvoet, which describes the use of a non-woven corrugated fabric for medical and surgical pads, said pads include the use of cellulose fiber reinforced with plastic; * No. 5,635,201 to Fabo which describes the use of a curable siloxane material coated on a vehicle surface and curing by heat to form a siloxane gel; * No. 5,685,832 to Chen et al, which describes a wound dressing comprising a woven cellulose acetate substrate and a partial solvent therein, the dressing of which releases, in a controlled manner, acetic acid to act as an agent therapeutic. * No. 3,285,245 to Eldridge et al., Which describes an absorbent wound dressing that has an absorbent backing and a non-absorbent face. Said bandage, although it has several qualities that can reduce adhesion or provide other benefits, incorporates lubricants and / or fluids or fluid release agents and uses fibers other than cellulose acetate to provide non-adhesion properties. Adhesive dressings and methods of preparing adhesive dressings are well known in the art as illustrated in US Pat. No. 4,595,001, and the patent references cited herein, from Potter (a surgical bandage comprising an adhesive layer to secure a bandage to a body), the teachings of which are incorporated herein by reference. Although the above bandages represent an improvement in reducing the adhesion of the bandage to wounds, other improvements in the field are highly desirable. In particular, an improved cellulose acetate dressing would be useful in medical techniques because cellulose acetate is chemotactic to attract white and hydrophilic blood cells. The chemotactic property for white blood cells of cellulose acetate fibers is desirable in a wound dressing because the white blood cells help fight the infection. The hydrophilic property is desirable because it helps to remove excess fluids. that can emanate from the surface of a wound during the healing procedure. Accordingly, the present invention is directed to providing said improved bandage. It is an object of the invention to provide a wound dressing made of cellulose acetate having improved non-stick characteristics. It is another object of the invention to provide a wound dressing made of cellulose acetate and a low level of siloxane finishing agent, said dressing having improved non-adhesion characteristics. It is an object of the invention to provide a self-adhesive bandage having a wound dressing pad attached thereto, said pad being made of cellulose acetate with or without a low level of siloxane terminating agent, and said pad having characteristics of no improved adhesion. It is another object of the invention to provide a biostat containing a wound dressing and / or self-adhesive bandage having a wound dressing attached thereto. Said bandage is partially or totally comprised of cellulose acetate, and has a low level of siloxane terminating agent applied thereto; and said bandage has improved non-adhesion characteristics.

BRIEF DESCRIPTION OF THE INVENTION The invention relates to a wound dressing which does not adhere to the surface of the wound or which has improved non-adhesion characteristics in relation to wound dressings known in the art. In one embodiment, the invention comprises a bandage of woven or non-woven cellulose acetate. In a preferred embodiment, the invention comprises a non-woven cellulose acetate fabric, and a particularly preferred nonwoven dressing comprises an interwoven material having a weight of about 20 to about 90 g / m2 (grams per square meter). Said embodiments may further comprise said additional substances at low levels of siloxane materials to finish the bandage or the fibers used to make the bandage and also impart more adhesion-reduction characteristics; and antibiological agents such as bactericides and phycidicides which can be incorporated in cellulose acetate beforehand if it is formed into a filament for use in the production of the bandage or said antibiologicals incorporated in a fiber that can be used together with the acetate fibers of cellulose to produce the bandage. In another embodiment, the invention relates to an article of manufacture comprising an adhesive tape having an adhesive on one side thereof and a wound dressing which adheres to a portion of the adhesive side of said adhesive. tape, wherein said wound dressing comprises one or a plurality of layers of a fabric comprising cellulose acetate fibers, cellulose acetate fibers containing biostat having a biostat content of from about 1% to about 5%, and a siloxane in the amount of from about 0.01% to about 0.0001%; wherein the amount of fibers containing biostat in the bandage is from about 1% to about 100% of the total fiber in the bandage.

DETAILED DESCRIPTION OF THE INVENTION The terms "antiobiological" or "biostat", and variations thereof, as used herein, mean any substance that has an effect on a biological organism, and in particular means bactericides, antibiotics, fungicides, herbicides, antimicrobials and substances similar ones that have an effect on biological organisms, both animals and plants. The term "bandage", as used herein, means any material applied to protect, fill, cover and generally isolate a wound from any other damage or from any undesirable contact. The material can be in any form such as a pad, gauze, bandage, sheet or similar form that can be used in medical treatments. The bandage can be used on its own or together with a medicinal substance or other substance applied to or contained therein, and may comprise multiple layers of cellulose acetate materials from which the bandage is made. The terms, "no adhesion" "no adherence", "non-sticky", "non-sticky", "non-sticky" and variations thereof, in similar terms, can be used interchangeably to refer to a bandage that does not adhere or stick to a wound, or that shows a reduced tendency to adhere to a wound in relation to other bandages. The bandage can be made of a woven or non-woven cellulose acetate, with non-woven being preferred. In addition, the bandage can be made only of cellulose acetate or in combination with another filament to fiber suitable for use in medical bandages, including polyesters, polyolefins, polyamides and cotton, with polyesters being preferred. All percentages herein are percentages by weight, unless otherwise specified.

Methods General Preparations The cellulose acetate containing the bandage of the invention may be a cross-linked, woven or non-woven material, with non-woven being preferred. The spinning process used to produce a cellulose acetate bandage can be either dry-spinned or wet-spun since said terms they are understood by the person skilled in the art. A description of filaments of cellulose acetate and fibers (hereinafter collectively referred to as "fibers"), in the materials and processes used to make said fibers, can be found in the "Encyclopedia of Chemical Technology, 4th Ed." (Iley., Interscience , John Wiley &Sons, New York), Vol. 10, pages 204-253 (non-woven fabrics), 598-624 (cellulose esters) and 696-726 (regenerated cellulosics), and are well known to those skilled in the art. The technique. The manufacture of the reticulated and woven fabrics is well known to those skilled in the art. The method used to incorporate the antibiologicals into a fiber is well known in the art as illustrated in the Patents of E.U.A. Nos. 3,959,556 and 4,343,853 to Morrison, which disclose the incorporation of an antimicrobial agent into a thermoplastic resin to produce a fiber having an intimately antimicrobial blend with the resin. Cellulose acetate is a thermoplastic substance. Woven fabrics can be prepared using cellulose acetate fibers by conventional tissue procedures known to those skilled in the art. Said techniques can be used to produce only one cellulose acetate fabric and a second fiber having an antibiological closely mixed with the resin of the fiber. Non-woven fabrics can be prepared using cellulose acetate fibers by conventional nonwoven techniques known to those skilled in the art. In the preferred embodiment of the invention, the nonwoven fabric is prepared according to the interwoven method. The interwoven method can be used to produce either only cellulose acetate fabrics or a fabric comprising cellulose acetate and a second fiber containing an antibiotic intimately mixed with the fiber. In the preferred embodiment, the fiber containing the antibiotic is cellulose acetate and the fiber containing the antibiotic is present in a fabric in an amount of greater than 0% to 100% of the total fiber of the fabric. The fibers used to produce a woven fabric? Non-woven fabrics are made using spinners having from 50 to about 250 openings therein to produce the filaments from about 1 to about 50 denier per filament (dpf), with 1-5 dpf being preferred. The heavier dpf materials are used when "multiple" layers are desired in a non-woven fabric, for example, to impart strength through a layer of smaller fibers, or when it is desired to give any fabric more "body" . The fabrics, particularly the interwoven fabric, are produced on a weight scale of from about 20 to about 90 g / m. After forming the fabric, the fabric is then stitched or punched to produce a fabric having from about 10 to about 200 openings per era.

Alternatively, the fabric can be used as formed or die cut or fired to form the openings. After the formation and firing of the fabric, the fabric may undergo optional additional treatments such as washings, the preferred embodiments of the invention, the fabric was washed and treated with a siloxane-containing solution comprising: 2.27 kilograms (Kg) 70% of Sentry NF30 and 30% of Nuwet 500 (both from Witco Chemicals, Greenwich, CT, USA) in approximately 226 liters of deionized or distilled water (11,325 kg per 226.8 liters). Those skilled in the art are familiar with the above siloxane materials and the invention teaches by means of the foregoing that similar silicone materials can be substituted from other sources. The siloxane treatment time was found in the 10-30 minute scale, and with approximately 15 minutes being a typical treatment time. After siloxane treatment, the fabric was usually washed with water to remove the excess silicone and dry. The amount of siloxane in the cloth after washing and drying is from about 0.01% to about 0.0001%. Then the fabric can be folded, cut and processed and packaged in another way for sale to the end user. The fabric was sterilized by any sterilization method known in the art, for example, by gamma irradiation where 27-34 KGy were delivered. When a bandage is applied to the wounds it may consist of one or more layers of the fabric of the invention. Typically, one of The 20 layers can be used, an exact number is determined by the nature and / or severity of the wound.

EXAMPLE 1 Cellulose Acetate Fabric Containing Siloxane and Biostat The use of the general procedures described above, filaments of 3 dpf were extracted from a plurality of spinners to produce a fiber subsequently used in the interlacing method to produce a nonwoven fabric of 70 g / m in weight with approximately 24 openings per was . The fabric was washed, treated with siloxane solution, dried, packed and sterilized using gamma radiation. Alternatively, a fabric may be prepared by using conventional fabric of cellulose acetate short fiber yarn, ie, a flat weave pattern lxl to a comparable fabric weight. The siloxane content is from about 0.01% to about 0.0001%.

EXAMPLE 2 Cellulose Acetate Fabric Containing Siloxane and Biostat The use of the general procedures described above, 3 dpf fibers, were extracted from the spinners, and the resulting fibers were used to produce a nonwoven interlacing fabric of 77 g / m 3 by weight.

One or a plurality of fibers used in the production of the fabric was a fiber containing the biostat Microban [2,4,4'-trichloro-2'-hydroxid phenyl, or alternatively, 5-chloro-2 (2, 4 -dichlorophenoxy) phenol], a chlorinated phenoxy material identical to one of those described in Morrison's patents. The Microban containing the fiber used in the preparation of the fabric of this example was the cellulose acetate fiber Celanese Acétate LLC, Charlotte, NC, U.S.A. Other biostat fibers useful in the practice of the invention include polyolefin, polyamide, polyester, polyacrylate, polyvinyl alcohol and similar fibers known to those skilled in the art. Generally, the biostat can be incorporated into the resin of the fabric in an amount from about 0.01% to about 5%. As used in this example, the amount of biostat incorporated in the fiber was about 2%. The amount of fiber containing biostat incorporated in a woven or non-woven fabric can be from about 1% to 100%. Preferably, the amount may be from about 1% to about 50% and most preferably from about 3% to about 30%. As used in this example, the amount of fiber containing biostat in the interlaced fabric was about 30%. The cloth was cooked, washed, treated with siloxane solution, dried, packed and sterilized using gamma radiation. The siloxane content is approximately 0.01% approximately 0.0001 ° FIELD TESTS The field tests were carried out in four hospitals in China, all the main centers of attention to people with burns, because burns commonly occur in China where kerosene heaters are commonly used for domestic heating during the months of winter and outdoor fires are used for cooking. As a result, a bandage evaluation of the invention and other bandages can be done more quickly due to the available number of patients. In addition, due to cost considerations, bandages are usually left on burns for longer periods before being changed, unless medical necessity or circumstances dictate otherwise. The directors of each burn care center were asked to help design a single study protocol that could be used to evaluate the bandage of the invention against burn dressings commonly used in China. Four different bandages were used in the field tests. These are: 1. Cotton Strip; 2. Kangda, a bandage commercially available in China . 3. CAYX, a "flat" cellulose acetate dressing commercially available from Yong Xing Company; and 4. CAM, the cellulose acetate bandage of the invention was prepared according to Example 2. The Kangda bandage is a nylon mesh having cotton material. The CAYX bandage is a "flat" cellulose acetate that has no discernible to another material such as petrolatum, siloxane or dioate, and is similar to the published Chinese patent 87 1 01823 A cited above. The CAM bandage was prepared according to Example 2. The bandages were applied in a standardized manner in a sufficiently large area of the body in each patient to whom the four bandages could be placed. A picture of each burn site was made on the patient evaluation sheet to record the order of application and location of each dressing. Each bandage sample was a minimum p of 10x10 m and sixteen (16) layers of thickness. Before placing the bandage on the burned surface, a thin layer of Silvadene TM cream was applied to each burn or bandage site. The Silvadene was reapplied at each subsequent bandage change. After application, the bandages were covered with a standard material such as the cotton gauze to hold the bandage in place. To bring the minimum any difference that could be caused by having multiple physical evaluators, each Change test site designated a physicist to be the primary evaluator who completed the patient evaluation form. Said form was completed at each change of bandage in the primary physical examination. The bandages were initially changed after 24 hours, and the change was subsequently extended to 48 hours as the wounds healed. Each bandage change resulted in a separate evaluation. The participants were patients who were hospitalized with a minimum of second degree burns in less than 50% of the body. The patients were between 15 and 55 years of age and were free of any medical conditions, such as diabetes, HIV and other immunosuppressed conditions that could affect wound healing. An objective number of participants of either sex were selected for field testing at each hospital site. A total of 270 patients from the hospital sites met in the tests. The results of the field test can be found in Tables 1-5. The pain was evaluated using a scale of 1-10 with (1) being painless and (10) being the worst pain. Adherence was also assessed using a scale of 1-10 with (1) being non-adherent and (10) meaning that the bandage was stuck to the wound. The appearance of the wound was evaluated using a scale of 10-100, with 100 investigating the worst appearance. The "P" value (pain value) is defined as 99% and for the invention it is significantly lower than cotton.

TABLE 1 Pain scores N = 270 patients Vendai e Average Score Value "P" vs. Cotton Cotton 4.01 Kangda 2.89 CAYX 2.70 CAM 2.02 < 0.01 The results in Table 1, pain, indicate that the CAM bandage contains Microsafe fibers and that it has a siloxane treatment that caused significantly less pain when it was removed than any other bandage. The CAM bandage had an average score of 2.02 out of a total of 262 readings (bandage changes) in contrast to an average score of 2.70 for the next best bandage, CAYX. The pain score for CAYX, the pain cellulose acetate bandage was approximately 35% higher than that of CAM, the bandage of the invention. The cotton bandage had the highest pain score, approximately twice that of the CAM bandage. There was no difference in the results when considering the age and sex of the patients.

TABLE 2 Pain scores by hospital Hospital ecturas Alaodón CAM Value "P" Shanghai 53 2.40 1.55 < 0.05 304 ° Military 37 3.27 1.43 < 0.01 Ji-Shui 120 4.40 2.52 < 0.01 Rui Tan 52 5.54 1.88 0.01 The overall trend in the scores remained consistent when the scores were divided by participating hospital as shown in table 2, indicating that the statistical data are adequate and that there were no abnormalities. The results of table 3, adherence scores, indicate that the CAM bandage contains fibers • p Microsafe and containing a silicone treatment that was significantly less adherent to a wound than any other bandage. The CAM bandage had an average score of 2.01 out of a total of 262 bandages (bandage changes), in contrast to an average score of 2.83 for the next best bandage, CAYX. The adhesion score for CAYX, the flat cellulose bandage, is approximately 40% greater than that of CAM, the cellulose acetate bandage of the invention. The cotton bandage had the highest adhesion score, approximately twice that of the CAM bandage. There was no differentiate in the results when considering the age and sex of the patients.

TABLE 3 Punctuations of adherence to wounds (N = 270 patients) Vendaie Average adherence Value "P" vs. Cotton 4.13 Kangda 2.93 CAYX 2.83 CAM 2.01 < 0.01 The overall trend in the scores remained consistent when the scores were divided by participating hospitals as shown in Table 4, indicating that the statistical data are adequate and that there were no abnormalities.

TABLE 4 Punctuations of adherence to wounds by hospital Hospital No. of readings Alaodón CAM Valor Shanghai 53 2.32 1.51 < 0.05 304th Military 37 3.95 1.43 < 0.01 Ji-Shui Tan 120 4.67 2.60 < 0.01 Rui Tan 52 5.29 1.75 < 0.01 The results of Table 5, score and appearance of the wound, indicate that the CAM bandage contains Microsafe fibers and that they have a siloxane treatment that resulted in a lower score and therefore were considered as indicators that the wound was healing properly. The CAM bandage had an average score of 18.58 in contrast to an average score of 20.25 for the next best CAYX bandage. The cotton bandage had an appearance score of 25.60. There was no difference in the results when considering the age and sex of the patients. Although judging the appearance of wounds is often very subjective, the doctors involved in the study wanted to include this as one of the factors to be evaluated. The appearance was judged after the bandages were removed and placed on the amount of the healthy appearance wound surface observed. The greater the amount of healthy wound surface observed, the lower the score.

TABLE 5 Scores of appearance of the wound Bandage Average score Value "P" vs. Cotton Cotton 25. 60 Kangda 23 54 CAYX 20. 25 CAM 18. 58 < 0.05 If an ideal wound dressing could be designed, the wound surface would be protected, and healthy granulated tissue would not be disturbed when removed, would not absorb blood and other fluids, would help promote wound healing by leukocyte chemotaxis. , would reduce the overall risk of infection and would be economical compared to other commercially available bandages. Although cotton has long been the standard dressing for use in burns and other wound healing, primarily because of its availability and low cost, it does not itself promote the healing procedure. Microscopically, cotton is a fiber that has a regular surface with numerous small protuberances on the surface of the fiber. It is said protuberances which cause the cotton fibers to stick uncomfortably to a wound surface. In contrast, cellulose acetate dressings, and in particular the CAM bandage described herein, have advantages over the cotton. The cellulose acetate fibers 7 generally have a smooth surface without interruptions or protuberances to be placed in a the wound. In view of the above, it is not surprising that cellulose acetate is less adhesive than cotton or other materials. It is noted that although CAYX and CAM bandages are made of a cellulose acetate fabric, the CAM bandage of the invention is superior to CAYX in all categories. Without being limited to any theory or explanation in particular, it is believed that the foregoing is the result of CAM including a biostat and a siloxane. Although this invention has been described with some emphasis on the preferred embodiments, it will be apparent to one skilled in the art that variations of the preferred embodiments may be used and it is intended that the invention may be practiced in a manner different from that specifically described in present, in medical and non-medical techniques. In the medical field, polyester or polyolefin fibers containing biostat, as indicated herein, can be used in place of biostat-containing cellulose acetate fibers. Additionally, the amount of siloxane in the wound dressing can be increased, being within the range of 0.0001% to about 2% by various methods such as the grafting of a siloxane to the fibers according to the methods known to the experts. in the art or as taught in the Patent of E.U.A. of Fabo cited above. Accordingly, the present invention includes all modifications comprised within the scope and spirit of the invention as defined in the following claims.

Claims (13)

NOVELTY OF THE INVENTION CLAIMS

1. - A fabric comprising cellulose acetate fibers, cellulose acetate fibers having a selected amount of a biostat therein, and a siloxane; characterized in that the biostat-containing fibers are from about 1% to about 100% of the fibers in the fabric, the siloxane is from about 0.01% to about 0.001% and said fabric is selected from the group consisting of woven and non-woven fabrics.

2. The fabric according to claim 1, further characterized in that the amount of fibers containing biostat in the fabric is in the range of about 1% to about 50%.

3. The fabric according to claim 2, further characterized in that the amount of fibers containing biostat in the fabric is in the range of about 3% to about 30%.

4. The fabric according to claim 1, further characterized in that the biostat content of the biostat-containing fibers is from about 0.01% to about 5%.

5. - The fabric according to claim 1, further characterized in that said fabric is a non-woven fabric, said biostat-containing fibers are from about 1% to about 30% of the total fibers, and said biostat-containing fibers contain from about 0.01% to about 5% biostat.

6. - The fabric according to claim 5, further characterized in that said fabric is an interwoven fabric.

7. The fabric according to claim 1, further characterized in that the cellulose acetate and the cellulose acetate fibers containing biostat are from about 1 to about 50 dpf.

8. The fabric according to claim 1, further characterized in that the cellulose acetate and the cellulose acetate fibers containing biostat are from about 1 to about 5 dpf.

9. The fabric according to claim 5, further characterized in that the cellulose acetate and the cellulose acetate fibers containing biostat are from about 1 to about 50 dpf.

10. The fabric according to claim 5, further characterized in that the cellulose acetate and the cellulose acetate fibers containing biostat are from about 1 to about 5 dpf.

11. The fabric according to claim 10, further characterized in that the fabric is an interwoven fabric.

12. A non-stick wound dressing comprising a fabric of (a) cellulose acetate fibers and cellulose acetate fibers having a selected amount of a biostat therein; and (b) a siloxane applied to said fabric; wherein: (i) the biostat-containing fibers are present in an amount of about 1% to 100% of the total fibers and the biostat content of the biostat-containing fibers is from about 0.01% to about 5%; (ii) cellulose acetate and cellulose acetate fibers containing biostat are from about 1 to about 50 dpf; (iii) the silicone is from about 0.01% to about 0.0001%.

13. - An article of manufacture comprising an adhesive tape having an adherent on one side thereof and a wound dressing adhering to a portion of the adhesive side of said tape, characterized in that said wound dressing comprises one or both plurality of layers and a fabric comprising cellulose acetate fibers, cellulose acetate fibers containing biostat having a biostat content of about 1% to about 5%, and a siloxane in the amount of about 0.01% to about 0.0001 %; wherein the amount of fibers containing biostat in the bandage is from about 1% to about 100% of the total fibers of the bandage.