Patent Description:
Each year, patients undergo a vast number of surgical procedures in the United States. Current data shows about twenty-seven million procedures are performed per year. Post-operative or surgical site infections ("SSIs") occur in approximately two to three percent of all cases. This amounts to more than <NUM>,<NUM> SSIs each year.

The occurrence of SSIs is often associated with bacteria that colonize wounds sites subsequent to surgery. During a surgical procedure, bacteria from the surrounding atmosphere may enter the surgical site and deposit in the wound. Additionally, bacteria can be spread during repeated opening and closing of the wound site when changing dressings or the like. Such bacterial contamination of the wound may lead to infection of and trauma to the patient. Accordingly, SSIs may significantly increase the cost of treatment to patients.

Additionally, the tissue at the wound site can be affected by hypothermia due to the low temperature of the operating room, and due to disruptions in the blood flow to the wound site caused by the removal of tissue and surgical injury to the tissue.

During surgery the temperature of the operating room is maintained at levels that provide comfort of the surgical staff. Due to the additional clothing worn and the inherent stress of the surgery on the doctors, nurses and other surgical staff, the operating room temperature is maintained at temperatures near <NUM> (<NUM>°F). This lower temperature as well as other factors of surgery including anesthesia, can cause the surgical patient to be hypothermic. This condition of hypothermia, commonly defined as <<NUM>°F (<NUM>) for core body temperature has been associated with significant morbidity and mortality. Also, there has been a threefold increase in the frequency of surgical site infections is reported in colorectal surgery.

Thermal post-surgical treatment of wound sites is beneficial to healing due to the increased blood perfusion. The increase in blood flow to the wound also increases oxygen tension, which has been shown to aid in wound healing and may reduce the risk of infection.

The use of a heat patch previously described can provide the necessary warming to the surgical site area to allow the body temperature to increase above the <NUM> (<NUM>°F) hypothermia condition back to a normal range or a normothermia state. This normothermia state allows for the significant reduction of the morbidity and mortality that is associated with hypothermia and will reduce the frequency of surgical site infections.

It would be advantageous to develop a non-contacting wound treatment system that provides thermal treatment and greater oxygen tension to the site of a wound, delivers a wound treatment agent, and helps to prevent microbial infections.

<CIT> describes a packaged antimicrobial medical device and a method of preparing the same.

<CIT> describes an apparatus which is said to apply heat to tissue from a level that does not contact the tissue in order to elevate the temperature of the tissue being treated towards normothermia. <CIT> describes a device comprising a housing having a handle end and a treatment end. The treatment end is configured to provide an antimicrobial treatment and a heat treatment. The treatment end comprises an applicator having an applicator surface for providing at least the heat treatment. The device includes a heat generation unit configured to heat the applicator surface in use, a source of antimicrobial agent, and a control unit operatively connected to at least the heat generation unit for controlling the heat generation unit.

<CIT> describes a device for transdermal drug delivery and administration of differing dosages at specific times of the day automatically pursuant to a pre-programmed dosage profile. The device includes a control and display unit, a two-part dispensing mechanism, a drug reservoir, an administration element, and a solvent removal element. The passive portion and drug reservoir are detachable along with the administration element for attaching a new dosing reservoir.

Presented herein is a wound treatment system, comprising a body structured and arranged to surround a wound area, the body having an opening above the wound area, a cover attached to the body and covering the opening, the cover suspended above the wound area, the opening and the cover forming an enclosed and empty wound treatment compartment, an autonomous heating element incorporated into the body or into the cover, and a medically useful agent evaporating or sublimating at an accelerated speed at a temperature from about <NUM> to about <NUM>, the medically useful agent in fluid communication with the compartment.

In one form, the amount of the agent is effective to inhibit bacterial infection of the wound.

In another form, the heating element is structured and arranged to heat the agent to a temperature sufficient to inhibit bacterial infection of the wound.

In yet another form, the medically useful agent is located on the heating element, or is located close enough to the heating element to receive radiant heat from the heating element.

In another form, the cover is a transparent or semi-transparent film, or a transparent or semi-transparent dome.

Advantageously, the medically useful agent is an antimicrobial agent, such as one selected from the group consisting of halogenated hydroxyl ethers, acyloxydiphenyl ethers, and combinations thereof.

In another form, the medically useful agent is impregnated in a strip of an inert carrier, and can be triclosan impregnated in a strip of melt-spun polymer.

In yet another form, dimensions of the enclosed wound treatment compartment are adjustable to accommodate wounds of different dimensions.

A wound treatment system according to the invention may be used in a method of wound treatment, comprising (i) enclosing a wound area with the wound treatment system comprising a body structured and arranged to surround a wound area, the body having an opening above the wound area, a cover attached to the body and covering the opening, the cover suspended above the wound area, the opening and the cover forming an enclosed and empty wound treatment compartment, an autonomous heating element incorporated into the body or into the cover, and a medically useful agent evaporating or sublimating at an accelerated speed at a temperature from about <NUM> to about <NUM>, the medically useful agent in fluid communication with the compartment, (ii) activating the heating element, thereby heating the medically useful agent, (iii) evaporating or sublimating portions of the medically useful agent to cause vapors of the medically useful agent to fill the enclosed wound treatment compartment, and (iv) contacting the wound with the medically useful agent vapors.

In one form, activating of the heating element provides radiant heat to the wound area.

In some forms, the cover is a transparent or semi-transparent film or a transparent or semi-transparent dome.

In yet another form, the medically useful agent is an antimicrobial agent selected from the group consisting of halogenated hydroxyl ethers, acyloxydiphenyl ethers, and combinations thereof.

In particular, the medically useful agent is triclosan impregnated in a strip of melt-spun polymer.

The forms disclosed herein are illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings and in which like reference numerals refer to similar elements and in which:.

Described herein is a non-contacting wound treatment system that provides thermal treatment and greater oxygen tension to the site of a wound, delivers an antimicrobial agent to the surface of the wound in a non-contact fashion through the gas or vapor phase above the wound, and helps to prevent microbial infections.

Each of the following terms written in singular grammatical form: "a," "an," and "the," as used herein, may also refer to, and encompass, a plurality of the stated entity or object, unless otherwise specifically defined or stated herein, or, unless the context clearly dictates otherwise. For example, the phrases "a device," "an assembly," "a mechanism," "a component," and "an element," as used herein, may also refer to, and encompass, a plurality of devices, a plurality of assemblies, a plurality of mechanisms, a plurality of components, and a plurality of elements, respectively.

Each of the following terms: "includes," "including," "has," "'having," "comprises," and "comprising," and, their linguistic or grammatical variants, derivatives, and/or conjugates, as used herein, means "including, but not limited to.

Throughout the illustrative description, the examples, and the appended claims, a numerical value of a parameter, feature, object, or dimension, may be stated or described in terms of a numerical range format. It is to be fully understood that the stated numerical range format is provided for illustrating implementation of the forms disclosed herein, and is not to be understood or construed as inflexibly limiting the scope of the forms disclosed herein.

Moreover, for stating or describing a numerical range, the phrase "in a range of between about a first numerical value and about a second numerical value," is considered equivalent to, and means the same as, the phrase "in a range of from about a first numerical value to about a second numerical value," and, thus, the two equivalently meaning phrases may be used interchangeably.

It is to be understood that the various forms disclosed herein are not limited in their application to the details of the order or sequence, and number, of steps or procedures, and sub-steps or sub-procedures, of operation or implementation of forms of the method or to the details of type, composition, construction, arrangement, order and number of the system, system sub-units, devices, assemblies, sub-assemblies, mechanisms, structures, components, elements, and configurations, and, peripheral equipment, utilities, accessories, and materials of forms of the system, set forth in the following illustrative description, accompanying drawings, and examples, unless otherwise specifically stated herein. The apparatus, systems and methods disclosed herein can be practiced or implemented according to various other alternative forms and in various other alternative ways.

It is also to be understood that all technical and scientific words, terms, and/or phrases, used herein throughout the present disclosure have either the identical or similar meaning as commonly understood by one of ordinary skill in the art, unless otherwise specifically defined or stated herein. Phraseology, terminology, and, notation, employed herein throughout the present disclosure are for the purpose of description and should not be regarded as limiting.

According to the present disclosure, a disposable dressing forms a compartment around and above a wound site and a volatile antimicrobial compound is allowed to sublimate/evaporate into the compartment. A heating element is included in the dressing, with heat stimulating wound healing and simultaneously accelerating sublimation/evaporation of the antimicrobial compound. Antimicrobial vapor saturates the enclosed compartment and deposits from the vapor phase onto the wound tissue. The antimicrobial agent present in the vapor phase within the enclosed compartment is continuously regenerated by continued heating of the antimicrobial agent and is continuously deposited onto the wound.

A first form of the presently disclosed wound treatment system is illustrated in <FIG> and <FIG>. The wound treatment system <NUM> includes a body <NUM>, which is configured to surround a wound <NUM>, such as a surgical incision or the like. Body <NUM> can be constructed of any biocompatible material, most preferably polymeric material typically used to form dressings and wound covering devices and known to a skilled artisan. The materials can be natural or synthetic polymers or combinations thereof, such as cellulose, polyesters, hydrocolloids, polyethylene, polypropylene, gelatin, and similar. A portion of body <NUM> can comprise an absorbent material, such a fibrous sponge, to absorb and remove wound exudates. Preferably, an adhesive (not shown) is disposed on at least a portion of the body <NUM> which is in contact with tissue or skin <NUM>. Any suitable adhesive known in the art of bandages or adherent wound dressings can be utilized, preferably pressure sensitive adhesive, such as acrylics-based pressure sensitive adhesive, to ensure body <NUM> is immobilized on and securely attached to tissue or skin <NUM>. The body <NUM> has an opening above the wound area and a film cover <NUM>, attached to the body <NUM> covering the opening. Film cover <NUM> can be transparent or non-transparent, but it is preferably transparent or semi-transparent. In this form, the cover <NUM> is a film suspended above the wound <NUM>. The film can be made of any suitable biocompatible polymer, such as polyesters, polyethylene, polypropylene, PVC, PET, and similar, most preferably having enough transparency so that the conditions of the wound <NUM> can be observed through film cover <NUM>. In some embodiments, film is impermeable or has very low permeability to water vapor and is substantially non-porous. The opening and the cover <NUM> form an enclosed and empty wound treatment compartment <NUM>. An autonomous heating element <NUM> is incorporated into the body <NUM>, which provides heat in direction B to both the underlying skin <NUM> and to an easily evaporating or sublimating medically useful agent <NUM>, such as an antimicrobial agent, in fluid communication with the compartment <NUM>.

Any medically useful volatile agent <NUM> can be used, that can evaporate or sublimate at a faster rate at temperatures slightly above the normal body temperature of <NUM> and saturate wound treatment compartment <NUM> with vapors of agent <NUM>. Preferably, agent <NUM> has limited or very minor evaporation or sublimation at ambient temperature such as <NUM>, but accelerated evaporation or sublimation at temperatures above <NUM> or <NUM> or <NUM> or <NUM>. In some embodiments, agent <NUM> has evaporation or sublimation rate that is at least <NUM> or <NUM> or <NUM> or <NUM> times higher at <NUM> or <NUM> or <NUM> than at <NUM>. In one embodiment, agent <NUM> comprises triclosan. In another embodiment, agent <NUM> comprises ethanol with additives rendering it less volatile at ambient temperature. In this form, the medically useful agent <NUM> is located on the body <NUM> containing heating element <NUM> and receives radiant heat sufficient to cause evaporation or sublimation in direction A, into the wound treatment compartment <NUM>. In one form, an optional spacer <NUM> is located between the body <NUM> and the cover film <NUM>. The spacer also can be a thermal insulating spacer positioned between the tissue or skin <NUM> and the heating element <NUM>, thus enabling higher temperature of the heating element supplied to the medically useful agent but lower temperature on the surface of the skin or tissue, preventing potential burns.

Advantageously, the medically useful agent <NUM> is an antimicrobial agent, which has a low evaporation or sublimation temperature, preferably from about <NUM> to about <NUM>. The temperature and the antimicrobial agents are selected to provide for sufficient evaporation or sublimation of the antimicrobial agent in order to provide for sufficient antimicrobial action. In one embodiment, the partial vapor pressure of the antimicrobial agent at <NUM> is at least about 1x10-<NUM> mm Hg, or even at least about <NUM>×<NUM>-<NUM> mm Hg. The antimicrobial agent can be one selected from the group consisting of halogenated hydroxyl ethers, acyloxydiphenyl ethers, and combinations thereof. In one form, the antibacterial agent is triclosan. The medically useful agent <NUM> can be impregnated in a strip of an inert carrier, such as triclosan impregnated in or deposited on a strip of paper or a strip of a melt-spun polymer, such as melt-spun high density polyethylene, available as Tyvek®, from DuPont de Nemours Company of Wilmington, DE.

The incorporation of heating element <NUM> also provides heat to the patient and wound site to help maintain normothermia and increase oxygen tension to the wound site.

In another form illustrated in <FIG>, the cover can be in the form of a transparent or semi-transparent dome <NUM>', which provides for a larger treatment compartment <NUM>. Dome <NUM>' can be made of any suitable biocompatible polymer, such as polyesters, polyethylene, polypropylene, PVC, PET, and similar, most preferably having enough transparency so that the conditions of the wound <NUM> can be observed through dome <NUM>. In all forms, the enclosed treatment compartment <NUM> comprises space not filled with any material immediately above the wound <NUM>, preventing any elements of the wound treatment system <NUM> from directly touching the wound <NUM> and causing irritation, potential contamination, disruption of wound healing, and painful removal. The presently disclosed non-contact wound treatment system <NUM> makes contact with the skin or tissue <NUM> only in the areas surrounding the wound, and does not contact the wound itself.

In <FIG>, the heating element <NUM> is incorporated into the body <NUM> similarly to the embodiment of <FIG>, or alternatively/additionally into covering dome <NUM>'; the antimicrobial source <NUM> is located on a bottom surface of dome <NUM>', receiving radiant heat therefrom and causing evaporation or sublimation into vapor, which travels in direction A toward the wound <NUM> and generally fills the compartment <NUM>. An optional absorbent pad <NUM>, such as a foam or sponge, can be provided around the wound <NUM> to absorb exudates from the wound.

<FIG> illustrates another form of the wound treatment system <NUM> in which the heating element <NUM> is disposed only on a portion of the underlying cover dome <NUM>', opposite the antimicrobial source <NUM>, which receives radiant heat from the heating element <NUM>. The radiant heat also is directed into and through treatment compartment <NUM> and toward wound site <NUM> along with the antimicrobial vapor in direction A.

Advantageously, in some embodiments the dimensions of the enclosed wound treatment compartment <NUM> are adjustable to accommodate wounds of different dimensions. In such embodiments body <NUM> has areas of stretchability that allow the body <NUM> to be expanded/extended around a larger wound, with cover film <NUM> and/or dome <NUM>' having enough slack or stretchability to accommodate expansion/extension of body <NUM>.

<FIG> are top and side cross-sectional views of the first form of a wound treatment system, with agent <NUM> shown disposed in an elongated strip form on one side of the heating element <NUM>. In other embodiments (not shown) agent <NUM> can be disposed also symmetrically on opposite side of the heating element <NUM>. Alternatively, agent <NUM> can be disposed as a singular spot deposit, or as a plurality of discrete deposits, or around the whole circumference of compartment <NUM>.

In some forms, at least a part of the body of the wound treatment system <NUM> comprises a self-contained heating element <NUM>, which upon activation generates heat and supplies heat to the skin or tissue <NUM> surrounding the wound <NUM>, providing thermal treatment to the area immediately surrounding the wound site, increasing blood perfusion and oxygen tension, and improving healing and reducing infection. No heat is supplied directly (via conductive heat transfer) to the wound <NUM>. The heating element <NUM> can be an air activated heating pack, based on iron powder, active carbon, water, and salt, with an air-permeable enclosure, as known in the art. Other types of heating elements are also suitable, such as heat packs utilizing heat of crystallization, electrically heated heat packs (particularly battery-powered), etc..

The wound treatment system may be used in a method of wound treatment, comprising (i) enclosing a wound with the wound treatment system comprising a body structured and arranged to surround a wound, the body having an opening above the wound area, a cover attached to the body and covering the opening, the cover suspended above the wound, the opening and the cover forming an enclosed and empty wound treatment compartment, an autonomous heating element incorporated into the body or into the cover, and an easily evaporating or sublimating medically useful agent in fluid communication with the compartment, (ii) activating the heating element, thereby heating the medically useful agent, (iii) evaporating or sublimating portions of the medically useful agent to cause vapors of the medically useful agent to fill the enclosed wound treatment compartment, and (iv) contacting the wound with the medically useful agent vapors.

In use, the medically useful agent is present in the vapor phase within the enclosed treatment compartment <NUM> and is continuously regenerated by continued heating of the medically useful agent <NUM> and by continuous deposition on the wound. The temperature of the heating element <NUM> in contact with or directed to the medically useful agent <NUM> is from about <NUM> to about <NUM>, or even from about <NUM> to about <NUM>. In this way, the medically useful agent <NUM> is supplied to the wound surface <NUM> throughout the treatment from the gas or vapor phase, constantly replenishing any medically useful agent that is absorbed by the tissue, carried away by exudates, dissolved, etc. The wound treatment system <NUM> can provide heat and supply the medically useful agent for an extended period of time, such as <NUM> hours, <NUM> hours, <NUM> hours, <NUM> hours, or <NUM> hours.

Alternatively, the medically useful agent <NUM> is supplied to the wound surface at the beginning of the treatment as the heating element heats up, and all of the medically useful agent <NUM> evaporates or sublimates from the medically useful agent element at the beginning of the treatment, i.e. within <NUM>-<NUM> minutes from the heating element reaching its operating temperature, or within <NUM>-<NUM> minutes from activating the heating element. The medically useful agent evaporated or sublimated from the antibacterial element then fills the enclosed treatment compartment <NUM> and deposits on the wound from the gas phase.

Specific forms will now be described further by way of example. While the following examples demonstrate certain forms of the subject matter disclosed herein, they are not to be interpreted as limiting the scope thereof, but rather as contributing to a complete description.

The experimental data were obtained with a model air-activated heating elements (<NUM> Hour Hand Warmers, Grabber, Grand Rapids, MI) surrounding a model wound represented by inoculated Petri dishes with <NUM> of 45C TSA agar containing about <NUM> logCFU/ml S. For testing, from <NUM> to <NUM> triclosan strips, each containing <NUM> of triclosan, were positioned on heating elements in proximity to inoculated Petri dishes. The assembly was covered creating an enclosed compartment around the inoculated Petri dishes, with triclosan patches within thusly formed compartment on the heating elements but not in contact with the inoculated Petri dishes. The inoculated Petri dishes were taken out after <NUM> hr and <NUM> hour exposure at ambient temperature (of which heating packs provided about <NUM> hours of heat) and incubated at <NUM>ºC for <NUM> hr to allow the bacterial colonies, if any, to grow and be evaluated. Controls tested included the same model without any heating elements; heating elements in a system with no triclosan; no heating, no triclosan for confirming inoculation and bacterial growth, no heating no triclosan no inoculation for confirming agar was not contaminated.

Tests of inventive devices tests # <NUM>-<NUM>, <NUM> had <NUM> heating elements and from <NUM> to <NUM> triclosan patches and demonstrated full inhibition of bacterial growth. Controls tests #<NUM>-<NUM>, <NUM>-<NUM> had either no heating and/or no triclosan and/or no inoculation. Tests #<NUM>-<NUM>, <NUM>, <NUM>-<NUM> had no heating; Tests #<NUM>-<NUM> had no triclosan; Tests <NUM>-<NUM> had no inoculation.

Comparison of control tests <NUM>-<NUM>, <NUM>-<NUM> to inventive device tests <NUM>-<NUM>, <NUM> indicates that in presence of heat elements even <NUM> strip of triclosan was sufficient to show full bactericidal effect on S. aureus with vapor transfer of triclosan.

Without heat elements, most tests indicated lack of antibacterial effect. However, one test, test #<NUM>, with maximum <NUM> strips of triclosan, showed full antibacterial effect after <NUM> hours, but still insufficient effect (partial growth) after <NUM> hours.

The experimental data demonstrated that heating elements enabled vapor phase delivery of triclosan to the model wound surface.

The systems and methods disclosed herein are applicable to the health care industry.

Claim 1:
A wound treatment system, comprising:
a body structured and arranged to surround a wound area, said body having an opening above the wound area;
a cover attached to the body and covering the opening, said cover suspended above the wound area;
said opening and said cover forming an enclosed and empty wound treatment compartment;
an autonomous heating element incorporated into the body or into the cover; and
a medically useful agent evaporating or sublimating at an accelerated speed at a temperature from about <NUM> to about <NUM>,
said medically useful agent in fluid communication with the compartment.