Abstract:
An illumination device comprises a housing, a power supply and at least one light source powered by the power supply. The at least one light source is adapted to emit radiation from the housing at one or more therapeutic wavelengths. The illumination device is positioned in proximity to an area for applying radiation to the area for a time and intensity sufficient to have a bacteriocidal effect.

Description:
CROSS-REFERENCES 
       [0001]    This application is related to U.S. provisional application No. 61/680,061, filed Aug. 6, 2012, entitled “LAVAGE DEVICES WITH UV LIGHT AND METHODS OF USE”, naming Kevin Brown as the inventor, and U.S. provisional application No. 61/751,490, filed Jan. 11, 2013, entitled “LIGHTING UNITS FOR USE WITH LAVAGE DEVICES”, naming Kevin Brown as the inventor. The contents of the provisional applications are incorporated herein by reference in their entirety, and the benefit of the filing date of the provisional applications are hereby claimed for all purposes that are legally served by such claim for the benefit of the filing date. 
     
    
     BACKGROUND 
       [0002]    An apparatus and method for using ultraviolet light (UV) with pulsatile lavage is described and, more particularly, an apparatus and method using UV light with a pulsatile lavage device at a surgical or wound site. 
         [0003]    Surgical site infections occur after an invasive procedure at the site of the surgery. Every year in the U.S. there are nearly 1.7 million occurrences of surgical site infections with approximately 99,000 cases resulting in death. Surgical site infections are an obvious burden to patients and physicians, but also to hospitals, requiring billions in treatment costs. 
         [0004]    A current approach to reducing surgical site infections is pulsatile lavage. A pulsatile lavage device is a manual irrigation device that directs a pressurized stream of saline fluid directly at a wound in order to disinfect and debride the wound. The pulsatile lavage device injects fluid into a wound area and uses a suctioning mechanism to remove debris and necrotic tissue. 
         [0005]    Ultraviolet light of a particular range of wavelengths, intensities, and durations can kill or inhibit growth of microorganisms. Specifically, ultraviolet radiation in the range of 200 nanometer (nm) to 300 nm is effective against airborne and surface bacteria, viruses, yeasts, and molds. For most microorganisms, the peak inactivation wavelength is at or about 260 nm. Mercury lamps produce UV light very efficiently at 254 nm and, therefore, this wavelength has become a standard wavelength. 
         [0006]    There is a need for an apparatus that combines UV light with pulsatile lavage for use at a wound or surgical site. The combined device will bring the germicidal capabilities of UV light to conventional pulsatile lavage in order to further decontaminate wounds and reduce surgical site infections. 
       SUMMARY 
       [0007]    An illumination device is described and comprises a housing, a power supply and at least one light source powered by the power supply. The at least one light source is adapted to emit radiation from the housing at one or more therapeutic wavelengths. The illumination device is positioned in proximity to an area for applying radiation to the area for a time and intensity sufficient to have a bacteriocidal effect. In one aspect, the radiation emitted is ultraviolet C radiation for a duration of between about 5 seconds and 2 minutes. 
         [0008]    A further illumination device is described and comprises a housing, a power supply and at least one light source powered by the power supply. The housing is configured to be mounted to a pulsatile lavage device. The at least one light source is adapted to emit radiation from the housing at one or more therapeutic wavelengths. The illumination device is positioned in proximity to an area for applying radiation to the area for a time and intensity sufficient to have a bacteriocidal effect. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  is a front side perspective view of an embodiment of an apparatus for using ultraviolet light with a lavage device. 
           [0010]      FIG. 2  is an exploded perspective view of an apparatus for using ultraviolet light with a lavage device as shown in  FIG. 1 . 
           [0011]      FIG. 3  is a top plan of an ultraviolet light unit for use with the apparatus for using ultraviolet light with a lavage device as shown in  FIG. 1 . 
           [0012]      FIG. 4  is a longitudinal cross-section of the ultraviolet light unit as shown in  FIG. 3 . 
           [0013]      FIG. 5  is a front side perspective view of another embodiment of an apparatus for using ultraviolet light with a lavage device. 
           [0014]      FIG. 6  is a circuit diagram for use with an apparatus for generating ultraviolet light. 
       
    
    
     DESCRIPTION 
       [0015]    Certain terminology is used herein for convenience only and is not to be taken as a limitation on the invention. For example, words such as “upper,” “lower,” “left,” “right,” “horizontal,” “vertical,” “upward,” and “downward” merely describe the configuration shown in the FIGs. Indeed, the components may be oriented in any direction and the terminology, therefore, should be understood as encompassing such variations unless specified otherwise. 
         [0016]    It is understood that although a UV light apparatus is described in detail herein with reference to an exemplary embodiment for use with pulsatile lavage, the UV light apparatus may be applied to, and find utility in, other devices and tools for medical and non-medical use. As described above, UV light is used in a wide variety of applications for disinfecting or sanitizing areas of exposure. Therefore, although the UV light apparatus will be described in detail herein as embodied in a device for medical use, it is not intended to be so limited. Moreover, the UV light apparatus may be used as a stand alone device and not necessarily in combination with any other device or function. Thus, the UV light apparatus described herein has general applicability to any circumstance wherein improvements in disinfection and sanitization are desired. 
         [0017]    Referring now to the drawings, wherein like reference numerals designate corresponding or similar elements throughout the several views, an embodiment of an apparatus for using ultraviolet light with a pulsatile lavage device is shown in  FIGS. 1 and 2  and generally designated at  20 . The UV light apparatus  20  comprises a housing  22  configured to be mounted to the lavage device  30 . The housing  22  accommodates a UV light apparatus, including a UV light source  24  and a power source  26  to power the UV light source for delivering UV light to a patient. A tubular wand  28  extends from the housing  22  to a distal outlet through which the UV light is emitted. 
         [0018]    The housing  22  is substantially cube-shaped, although the housing may be formed in various other suitable shapes and sizes. The housing  22  may be formed of a relatively rigid material to protect the components. In one embodiment, the housing is constructed from a rigid plastic, such as polyvinyl chloride. A removable cover  23  is provided for selective access to the interior of the housing  22 , such as for removing or replacing batteries when used as the power source  26 . 
         [0019]    The UV light source  24  is disposed within the housing  22  and is adapted to emit UV light to an area being treated. In one embodiment, the light source  24  comprises a light emitting diode (LED). A suitable LED for this application is available from HexaTech. In the FIGs., two LED&#39;s are shown for producing a desired optical intensity. The LED&#39;s  24  are positioned at the outlet of the tubular wand  28  projecting from the housing  22 . This arrangement improves light localization at the wound site, minimizes scatter and enhances the germicidal effect. In addition, selecting the length of the wand  28  allows for adjustment of the UV dosage. The outlets of the wand are covered by lenses  40  to protect the LED&#39;s  24 . Intermediate wires or cables (not shown) operatively connect the LED&#39;s  24  and the power source  26  for delivering power to the light source. 
         [0020]    In another embodiment, the light source  24  may include a mercury-vapor lamp, such as a mercury vapor low pressure lamp or a medium pressure lamp. Other embodiments of the UV light apparatus  20  may comprise a plurality of UV light sources, which may be the same or may be different. It is understood that the UV light source  24  may be remote from the housing  22 , wherein an optical cable (not shown) is operatively connected to the light source  24  for delivering UV light to the desired area. 
         [0021]    The power source  26  may include one or more disposable or rechargeable batteries, which fit within the housing. In one embodiment, the batteries are alkaline or lithium batteries. For example, three coin cell batteries are shown in the  FIGS. 3 and 4 . When combined, the three 3V batteries produce 9V of power for powering the LED&#39;s  24 . A beryllium metal strip (not shown) may be placed at the top and bottom, respectively, of the stack of batteries, providing a conductive surface with a large contact area to which the power wires or cables can be soldered. Dielectric tape can also be used to hold the battery stack together and insulate the batteries from other metal parts of the circuit. 
         [0022]    Alternatively, the power source  26  may be remote from the light source  24  with a power cord extending between the power source and the light source. An external power source  24  can also be used, such as an AC power supply connected to the light source  24  via one or more wires or cables. 
         [0023]    A switch  42 , shown as a toggle switch ( FIGS. 2-4 ), is provided to actuate the power source  26  for turning the light source  24  on and off. The switch  42  may be positioned at any preferred location on the housing  22 . Electrical connections (not shown) extend between the switch  42  and the power source  26  within the housing  22 . 
         [0024]    An embodiment of a circuit for the UV light apparatus  20  is shown in  FIG. 5 . The circuit comprises the power source  26 , the switch  42 , two sets of resistors  44  and two LED&#39;s  24 . Each resistor is wired in series with an LED and the LED&#39;s are wired in parallel with each other. The components of the circuit are soldered onto a circuit board  46  ( FIGS. 3 and 4 ). As described above, the switch  42  is connected to the power source  26  and the first branch of the circuit, including the first LED (UVCLED 1 ). When the switch  42  is closed, the circuit is complete and current can flow to the LED&#39;s. In the closed circuit, V 1 =V 2 =V 3 . The intensity of each diode is determined by the amount of forward current that flows through the diode. Therefore, the intensity of the diode will be a function of the associated resistor  44  and the power source  26 . LED&#39;s have a maximum forward current to which they can be exposed before failure. To avoid failure of an LED, the resistance values are chosen such that the forward current will be high enough to produce sufficient optical intensity while not exceeding the maximum forward current specification for the LED. The Node Voltage Method is used to determine the proper resistance values. For example, the Node Voltage Equation for branch 1 (UVCLED1) is: 
         [0000]    
       
         
           
             
               
                 
                   V 
                   2 
                 
                 - 
                 
                   V 
                   
                     f 
                      
                     
                         
                     
                      
                     1 
                   
                 
               
               
                 R 
                 1 
               
             
             = 
             
               I 
               
                 f 
                  
                 
                     
                 
                  
                 1 
               
             
           
         
       
     
         [0000]    , where I f1  is the maximum forward current for the LED. The same analysis seen above can be applied to each branch of the circuit depending on the type of LED used. The configuration of the circuit will remain the same, but the resistors and power source can change to accomodoate different LED&#39;s. 
         [0025]    The lavage device  30  comprises a body  32  for accommodating an irrigation system and a suction system. In one embodiment, the body  32  of the lavage device  30  is sized to be grasped and manipulated by surgical personnel during the surgical procedure. Alternatively, the body  32  of the lavage device  30  may be various sizes and shapes, depending upon the context of use. For example, the body  32  may be sized and shaped such that the lavage device  30  fits within the patient. Each of the irrigation system and the suction system includes a power source. The power source may be shared between the irrigation and suction systems, or each may include a dedicated power source. Accordingly, the body  32  of the lavage device  30  may also include one or more switches to actuate one or more of the irrigation system, the suction system, or even the UV light apparatus  20 . 
         [0026]    The irrigation system of the lavage device  30  is configured for moving a fluid to the patient. A variety of fluids may be used, including but not limited to saline and water. The fluid may also include an antiseptic or antifungal solution. The irrigation system includes a conduit  34  with an inlet for receiving the fluid from a reservoir or other fluid source and an outlet  35  through which the fluid is expelled to the patient. The length of the conduit  34  may vary depending upon the application. The irrigation system may also include a pump for moving the fluid through the conduit  34  to the patient. 
         [0027]    The suction system removes fluid from the patient after it has been expelled by the irrigation system. The suction system includes a conduit  36  with an inlet  37  adapted to be positioned in proximity to the patient and configured for receiving the fluid from the patient. The length of the conduit  36  of the suction system may vary depending upon the application. A pump may also be operatively connected to the conduit  36  for moving the fluid. 
         [0028]    In the embodiment shown in the FIGs., both conduits  34 ,  36  may extend outwardly of the body  32  and terminate in a distal nozzle portion  38  defining the outlet  35  of the irrigation system and the inlet  37  of the suction system. A variety of different nozzle configurations may be available to surgical personnel during the surgical procedure. A nozzle with the suitable distal ends of the conduits  34 ,  36  can be attached to the body  32  and used in a surgical procedure as necessary for the circumstance. 
         [0029]    As noted above, it is understood that the UV light apparatus  20  as described herein may be used with a variety of different lavage devices. A suitable lavage device for use with UV light apparatus  20  is sold as the INTERPULSE and is available from Stryker Instruments. 
         [0030]    In one embodiment, the UV light apparatus  20  is manufactured as a component of a lavage device  30 . In this arrangement, the UV light apparatus  20  is accommodated within a monolithic body of the lavage device  30 . The UV light apparatus  20  and the lavage device  30  may share a power source and circuitry. 
         [0031]    In another embodiment, the UV light apparatus  20  may be a self-contained unit that can be selectively attached to the body  32  of the lavage device  30 . In one embodiment, an attachment member  48  comprising a double-sided adhesive foam strip is used between the housing  22  of the UVC light apparatus  20  and the body  32  of the lavage device  30 . The adhesive strip  48  allows the UV light apparatus  20  to be secured to a variety of surfaces without the need for customized attachment. In addition, the housing  22  of the UVC light apparatus  20  has both curved and flat surfaces to correspond to curved or flat attachment surfaces on the lavage device  30 . 
         [0032]    The UVC light apparatus  20  is positioned such that UV light emitted is directed to the area being treated by the lavage device  30 . As shown in  FIGS. 1-4 , the UVC light apparatus  20  is attached to a top surface of the lavage device  30 . More particularly, the light source  24  is positioned at the distal end of the wand  28  adjacent the nozzle  38  defining the outlet and inlet of the irrigation and suction systems, respectively. In other embodiments, the light source  24  may be positioned at different positions relative to the body  32  of the lavage device  30 , and the UVC light apparatus  20  may be shaped or sized accordingly. 
         [0033]    Other means for attaching the UVC light apparatus  20  to a lavage device  30 , or any other medical or non-medical device or tool, are contemplated. Such means may provide for permanent or temporary attachment to the lavage device  30 . In one embodiment, the attaching means may include tabs configured to engage with and connect with the lavage device  30 , for example, in a groove on the lavage device. Flexible fingers can be configured to flex outward when the UVC lighting apparatus  20  is being attached to extend around the lavage device  30 . The fingers seat on opposing exterior surfaces of the lavage device  30  and apply an inward compressive force to maintain attachment with the lavage device. In another embodiment, attaching means on the UVC lighting apparatus  20  includes a tab with a receptacle to receive a mechanical fastener. The fastener extends through the receptacle and into the lavage device  30  to maintain the attachment. Attachment of the UVC light apparatus  20  to the lavage device  30  may also accomplish an electrical connection between the one or more systems and the UVC light apparatus. 
         [0034]    The UVC light apparatus  20  is configured to emit and direct UV light onto a surgical area. In one embodiment, the light source  24  emits UV-C light with sufficiently short wavelengths destructive to bacteria, viruses, and other micro-organisms. In some embodiments, the light source  24  emits UV light within a spectrum of between about 100-280 nm, and in a more specific range of between about 240-280 nm. In one specific embodiment, the UV light is at a wavelength of about 254 nm. The UV light is mutagenic to the bacteria, viruses, and other micro-organisms and breaks the molecular bonds within micro-organismal DNA. This bond breaking destroys the DNA, which either destroys the element, renders the element harmless, or prohibits the growth and reproduction. 
         [0035]    To effectively kill bacteria, the UV lighting apparatus  20  must provide an adequate energy dosage at the appropriate wavelength. The minimum effective germicidal energy dose for UV light is 3 mJ/cm 2 . The wavelength range most effective in killing the relevant strains of bacteria is between 200 and 280 nm, with 265 nm being the optimum wavelength. Thus, a preferred LED emits light at a wavelength of 265 nm (±5 nm). This wavelength will effectively kill bacteria if the energy dosage is above 3 mJ/cm 2 . 
         [0036]    The total UV dosage is a function of optical power, contact area, and time of exposure. A preferred exposure time can be up to 120 seconds or more, based on surgical observation and previous studies using UV light to kill bacteria. The remaining design parameters are adjusted by varying the distance to target area, viewing angle, and the number of LED&#39;s. 
         [0037]    When the UV light apparatus  20  used with a lavage device  30 , the lavage device  30  is operated to deliver a fluid through the outlet  35  of the conduit  34  of the irrigation system to a surgical site of the patient. The fluid is removed from the surgical site of the patient through the conduit  36  of the suction system. UV light is selectively emitted from the light source  24  to the surgical site while delivering and removing the fluid. This method combines tissue debridement with the antimicrobial effects of UVC light. In this application, the UV light apparatus  20  may be used for a variety of medical purposes, including but not limited to cleaning and rinsing wounds, and irrigating and washing an organ. 
         [0038]    Although the UVC light apparatus has been shown and described in considerable detail with respect to only a few exemplary embodiments thereof, it should be understood by those skilled in the art that we do not intend to limit the apparatus to the embodiments since various modifications, omissions and additions may be made to the disclosed embodiments without materially departing from the novel teachings and advantages, particularly in light of the foregoing teachings. Accordingly, we intend to cover all such modifications, omission, additions and equivalents as may be included within the spirit and scope of the UVC light apparatus as described herein and defined by the following claims. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents but also equivalent structures. Thus, although a nail and a screw may not be structural equivalents in that a nail employs a cylindrical surface to secure wooden parts together, whereas a screw employs a helical surface, in the environment of fastening wooden parts, a nail and a screw may be equivalent structures.