Illuminated bandage and method for disinfecting a wound

An illuminated bandage and method of disinfecting a wound. The illuminated bandage includes a power source, a light source coupled to the power source to generate light and a patch. The patch includes a supporting medium and at least one light diffusing element in the supporting medium and optically coupled to the light source. The light diffusing element outputs light to promote a photochemical reaction to disinfect a wound surface proximate thereto.

BACKGROUND

This disclosure pertains to a light delivery system, and more particularly to an illuminated bandage for disinfecting a wound.

Band-aids or bandages typically include an anti-bacterial application or disinfect that is applied to a wound to kill bacteria or prevent infection to the wound. Bandages typically include an anti-bacterial treatment applied to the wound to decontaminate and clean the surface. The anti-bacterial treatment is typically applied to an absorptive material, such as cotton and held in contact with the wound via an adhesive or elastic wrap. It is desirable to provide a means for disinfecting a wound that does not rely solely on the application of an anti-bacterial lotion to the wound.

SUMMARY

In accordance with one embodiment, an illuminated bandage for disinfecting a wound is provided. The illuminated bandage includes a power source, a light source coupled to the power source to generate light and a patch. The patch includes a supporting medium and at least one light diffusing element disposed in the supporting medium and optically coupled to the light source. The light diffusing element outputs light to promote a photochemical reaction to disinfect a wound surface proximate thereto.

In accordance with another embodiment, a method of disinfecting a wound is provided comprising the steps of providing a patch having one or more light diffusing elements disposed in a supporting medium and applying the patch to a wound surface. The method also includes the steps of generating light having a wavelength for promoting photochemical reaction, and applying the light to the one or more light diffusing elements to promote a photochemical reaction to disinfect the wound surface.

DETAILED DESCRIPTION

Reference will now be made in detail to the present preferred embodiments, examples of which are illustrated in the accompanying drawings. Whenever possible, the same reference numerals will be used throughout the drawings to refer to the same or like parts.

The following detailed description represents embodiments that are intended to provide an overview or framework for understanding the nature and character of the claims. The accompanied drawings are included to provide a further understanding of the claims and constitute a part of the specification. The drawings illustrate various embodiments, and together with the descriptions serve to explain the principles and operations of these embodiments as claimed.

Referring toFIGS. 1-5, an illuminated bandage10is illustrated for disinfecting a wound on a living being (e.g., person), such as a flesh wound on the surface of a hand and/or arm50. The illuminated bandage10has a patch12configured to engage the surface proximate to a wound, such as the outer skin of a living being so as to cover the flesh wound in the skin. The patch12may include an elastic covering that covers the skin and wraps around the hand and/or arm as shown inFIGS. 3 and 4. In other embodiments, the patch12may include an adhesive for adhering to the skin. Other securing arrangements may be utilized to position the patch12proximate to the wound.

The illuminated bandage10employs an active light and an optional photocatalyst to promote a photochemical reaction in the volume on the surface of the hand and/or arm50to disinfect the hand and/or arm to treat the wound. The light applied to illuminate the wound may include light having a wavelength that serves to kill germs or inhibit the growth of microorganisms, such as bacteria. The light may be used alone or may be used in combination with a photocatalyst such as rutile TiO2. The light wavelength may be in the range of 200 nm to 2000 nm, according to one embodiment. According to a specific embodiment, an ultraviolet (UV) light having a wavelength in the range of 200 to 400 nm may be used. The light may include a combination of wavelengths and may include a red laser light that is known to help increase sterility. Further, combinations of infrared (IR) light can also be used as an additional heat source for accelerating the photochemical processes.

The illuminated bandage10includes at least one electrically powered light source16for generating and supplying an active light with select wavelength(s) to promote the photochemical reaction. The light source16may be a collimated or Lambertian light source. The light source16may include one or more lasers, light emitting diodes (LEDs), incandescent bulbs, ultraviolet lamps or a combination of light sources. The light source(s)16may generate light having a unique color or may combine various colors, such as red, green and blue light sources to generate custom colors. In one embodiment, one or more ultraviolet light sources are employed.

The illuminated bandage10also includes at least one light diffusing element30operatively coupled to the light source16to receive the light supplied by the light source16and disperses the light. The illuminated bandage10includes a patch12that includes a supporting medium22and the at least one light diffusing element30. The light diffusing element30may be woven in the supporting medium22and optically coupled to the light source16. The light diffusing element30outputs light to promote a photochemical reaction to disinfect the wound surface proximate thereto. The light diffusing element30is a high scatter light transmission element that receives the light generated by light source16and scatters and outputs the light to the wound surface to promote a photochemical reaction to disinfect the wound. The high scatter light transmission achieved with the light diffusing element30has a light attenuation of 0.5 dB/meter or greater. The light diffusing element30may include one or more light diffusing fibers according to one embodiment disposed within the supporting medium22, such as is shown inFIG. 5. According to another embodiment, the light diffusing element30may include one or more light diffusing rods.

The powered light source16may be powered by a power supply14that supplies electrical power. The power supply14may include a portable battery supply, such as one or more batteries for providing electric current to the light source16. The one or more batteries may be primary or secondary electrochemical cells. In other embodiments, the power supply may be a fixed power supply. The power source14and light source16may be located remote from the patch12or may be coupled to the patch12.

The illuminated bandage10includes a supporting medium22which may include a woven material. The supporting medium22may include an absorptive material, such as cotton. The light diffusing element30is disposed within the woven supporting medium22and may be woven into the supporting medium22. The light diffusing element30is able to produce light that substantially penetrates the supporting medium22particularly between the light diffusing element30and the wound. The patch12further includes an outer reflective layer24which has a reflective underlying surface that reflects light towards the wound proximate the underside of the bandage10.

The illuminated bandage10may further include a low scatter light transmission medium18coupled between the light source16and the light diffusing element30. According to one embodiment, the low scatter light transmission medium18may include an optical fiber designed to transmit light with low signal loss. The low scatter light transmission achieved with the transmission medium18has a light attenuation of less than 0.5 dB/meter. The low scatter light transmission medium18is shown in one embodiment coupled to the light diffusing element30by way of an optical coupler20. It should be appreciated that the low scatter light transmission medium18may otherwise be operatively coupled to the light diffusing element30using various optical connections including splices, butt couplings and other light transmission couplings.

The low scatter light transmission medium18advantageously allows light generated by the light source16to be transmitted a substantial distance with low light signal loss to the patch12containing the light diffusing element30. The low scatter light transmission medium18may be located in a separate room from the patch12which may be located in a clean room such that the light diffusing element30may be employed as a flexible remote light illuminator that allows continuous sterilization and wet, explosive or other sterile environments while positioning the light source16and power supply14outside of the clean room. As such, the light source16does not need to be sterilized and may be electrically powered from outside the clean room.

The low scatter light transmission medium18may include a transmission fiber that may be a single fiber, a bundled (or ribbonized) collection of fibers, a plastic optical fiber (POF), or other light transmission medium. The low scatter light transmission medium18may employ a fused silica rod, according to another embodiment, that can also be used as efficient delivery of light from the light source16to the light diffusing element30. The low scatter transmission medium18may be connected to the light diffusing element30by the optical coupler20or by butt coupling to the light diffusing element30.

The light diffusing element30may be configured as a single light diffusing fiber or may be bundled (or ribbonized) collections of light diffusing fibers. The light diffusing fiber may be flexible, thus allowing ease in installation within the patch12. In one embodiment, the light diffusing fiber has a diameter of less than 1,000 microns, or more particularly of about 250 microns. In other embodiments, the light diffusing element may be more rigid such as in the form of a light diffusing rod having a diameter greater than 1,000 microns.

One embodiment of a light diffusing fiber30is illustrated having a typical cross-sectional structure shown inFIG. 1. The light diffusing fiber30may include the formation of random air lines or voids in one of the core and cladding of a silica fiber. Examples of techniques for designing and forming such light diffusing fibers may be found, for example, in U.S. Pat. Nos. 7,450,806; 7,930,904; and 7,505,660, and U.S. Patent Application Publication No. 2011/0305035, which are hereby incorporated by reference. The light diffusing element30has a glass core32which may include an F-doped core. An SiO2cladding layer34having air lines for scattering light is shown surrounding the core32. The cladding layer34may be formed to include air lines or voids to scatter the light and direct the light through the side walls39. It should be appreciated that the random air lines34may be disposed in the core32or in the cladding 36 or in both, according to various embodiments. It should be appreciated that high scattering losses are generally preferred in the light diffusing fiber30. A low index polymer primary protective layer36generally surrounds the cladding layer34. Additionally, an outer secondary layer38may be disposed on the primary protective layer36. Primary protective layer36may be soft and liquidy, while secondary layer38may be harder.

The secondary layer38may include a photoreactive agent according to one embodiment. The photoreactive agent may be provided as the secondary coating having a hardness greater than the first cladding coating. The photoreactive agent may include materials such as TiO2, W2O3, and other catalytic elements that photo-oxidizes when the light activates the material.

Scattering loss of the light diffusing fiber30may be controlled throughout steps of fiber manufacture and processing. During the air line formation process, the formation of a greater number of bubbles will generally create a larger amount of light scatter, and during the draw process the scattering can be controlled by using high or low tension to create higher or lower loss, respectively. To maximize loss of light, a polymeric cladding may be desirably removed as well, over at least a portion of the light diffusing fiber30length if not all. Uniform angular loss in both the direction of light propagation, as well as in the reverse direction can be made to occur by coating the light diffusing fiber30with inks that contain scattering pigments or molecules, such as TiO2. An ultraviolet light source may be used as well, with a fluorescent dye or phosphor materials applied to the fiber cladding (effectively down converting the ultraviolet wavelength of light with approximately 100 percent efficiency to a desired wavelength). Use of such fluorescence down-conversion creates very uniform angular light distribution. The high scattering light diffusing fiber30may have a modified cladding to promote scattering and uniformity. Intentionally introduced surface defects on the light diffusing fiber30or core or cladding may also be added to increase light output, if desired.

The light diffusing fiber30may have a region or area with a large number (greater than 50) of gas filled voids or other nano-sized structures, e.g., more than 50, more than 100, or more than 200 voids in the cross section of the fiber. The gas filled voids may contain, for example, SO2, Kr, Ar, CO2, N2, O2or mixture thereof. The cross-sectional size (e.g., diameter) of the nano-size structures (e.g., voids) may vary from 10 nanometers to 1 micrometer (for example, 15 nanometers to 500 nanometers), and the length may vary depending on the area of the surface to be disinfected.

While the light diffusing element30is shown and described herein as a light diffusing fiber having air lines, it should be appreciated that other light scattering features may be employed. For example, high index materials such as GeO2, TiO2, ZrO2, ZnO, and others may be employed to provide high scatter light transmission. It should further be appreciated the light diffusing element30may be a light diffusing rod that is less flexible, has a larger diameter and may have no coating.

A method of disinfecting a wound by promoting a photochemical reaction at the surface of the wound with the use of the illuminated bandage10will now be described. The method includes the step of providing a patch12having one or more light diffusing elements30woven into or otherwise disposed in a supporting medium22. The patch12is applied to a wound surface. The method includes generating light having a wavelength for promoting photochemical reaction, and applying the light to the one or more light diffusing elements30to promote photochemical reaction to disinfect the wound.

The method may further include the step of delivering the light from a light source16to the light diffusing element30via a low scatter light transmission medium18. The method may include providing electrical power from a battery14to power a light source to generate the light. The light diffusing element30may be a light diffusing fiber having a glass core, a cladding, and a plurality of light air lines disposed in one of the core and the cladding. At least one coating is disposed on the cladding, the at least one coating including a photoreactive agent. The light has at least one wavelength in the range of 200 nanometers and 2,000 nanometers, and may include ultraviolet light. The supporting medium22may include absorptive material. The patch12may include a plurality of light diffusing elements30, wherein the light is applied to the plurality of light diffusing elements30.

The illuminated bandage10may be used to disinfect an exposed wound in the flesh of the skin of a living being by applying the patch12to cover the skin including the wound area. This may be achieved with an elastic cover worn over the skin or wrapped around the skin. Alternatively, an adhesive may be used to adhere the patch to the skin. With the patch12applied to the skin, the light diffusing elements30generate light proximate to the wound to disinfect the wound. It should be appreciated that the illuminated bandage10could also be employed to disinfect an internal wound in which the patch is located internal to the body proximate to the wound.

Accordingly, the illuminated bandage10and method advantageously delivers light from a light source16coupled to a power source14to generate light to a light diffusing element30which outputs light to promote a photochemical reaction to disinfect a wound surface proximate thereto. The light diffusing element30is disposed in a supporting medium22of a patch12and optically coupled to the light source16. As such, the illuminated bandage10disinfects a wound with the light in a manner that is safe, easy to use and clean.

Various modifications and alterations may be made to the examples within the scope of the claims, and aspects of the different examples may be combined in different ways to achieve further examples. Accordingly, the true scope of the claims is to be understood from the entirety of the present disclosure in view of, but not limited to, the embodiments described herein.