Abstract:
Disclosed herein are several embodiments of a negative pressure apparatus and methods of using the same in the treatment of wounds. Some embodiments are directed towards improved fluidic connectors configured to transmit irrigation fluid and to apply aspiration to a wound, for example using softer, kink-free conformable layers. Some embodiments may comprise a first channel for delivering irrigation fluid to the wound and a second channel for transmitting negative pressure and removing fluid comprising irrigation fluid and wound exudate from the wound, wherein the channels comprise a flexible spacer material. Some embodiments are directed toward an irrigation manifold attachable to or incorporated as part of a distal end of an irrigation and aspiration fluidic connector.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. Provisional Application No. 61/822,254, filed May 10, 2013, the entirety of which is hereby incorporated by reference. 
     
    
     BACKGROUND 
       [0002]    1. Field of the Invention 
         [0003]    Embodiments described herein relate to apparatuses, systems, and methods the treatment of wounds, for example by applying irrigation and aspiration to a wound via a fluidic connector. 
         [0004]    2. Description of the Related Art 
         [0005]    The treatment of open or chronic wounds that are too large to spontaneously close or otherwise fail to heal by means of applying negative pressure to the site of the wound is well known in the art. Negative pressure wound therapy (NPWT) systems currently known in the art commonly involve placing a cover that is impermeable or semi-permeable to fluids over the wound, using various means to seal the cover to the tissue of the patient surrounding the wound, and connecting a source of negative pressure (such as a vacuum pump) to the cover in a manner so that negative pressure is created and maintained under the cover. It is believed that such negative pressures promote wound healing by facilitating the formation of granulation tissue at the wound site and assisting the body&#39;s normal inflammatory process while simultaneously removing excess fluid, which may contain adverse cytokines bacteria. However, further improvements in NPWT are needed to fully realize the benefits of treatment. 
         [0006]    In previously filed U.S. Pat. Nos. 7,524,315 and 8,105,295, the entireties of each of which are hereby incorporated by reference, apparatuses, wound dressings, and methods for aspirating, irrigating and cleansing wounds are described. In some of the embodiments described therein, a wound is treated by the application of topical negative pressure (TNP) therapy for aspirating the wound, together with the further provision of additional fluid for irrigating and/or cleansing the wound, which fluid, comprising both wound exudates and irrigation fluid, is then drawn off by the aspiration. The aspiration and irrigation are typically provided via conduits passing through the dressing into the wound cavity. 
         [0007]    Whilst such treatment methods work well in practice, the stiffness of the aspiration and irrigation conduits in such close proximity to the wound site can adversely affect the healing process. Patient movement or pressure onto the wound dressing may bring the healing wound into contact with the relatively inflexible conduits. Such force can cause disturbance of a wound bed which can damage a wound site. This can potentially cause delays in healing of the wound site. These conduits can also cause discomfort to the patient. The ability to create a fluid tight seal about the area where the conduits pass through the wound dressing can also be challenging. 
         [0008]    It will also be appreciated that aspiration and irrigation conduits are prone to obstruction. The conduits may become obstructed by movement of the patient, which may cause part of the tube to bend and form a kink or may place pressure onto the tubing, substantially or fully blocking the flow of fluid through the tubing. This can reduce or eliminate the negative pressure and/or irrigation fluid being transmitted to the wound site. In embodiments employing a separate canister for fluid collection, obstruction of the aspirant conduit can also result in accumulation of excess wound exudate at the wound site. 
       SUMMARY OF THE INVENTION 
       [0009]    Certain embodiments disclosed herein relate to improved fluidic connectors for providing aspiration and irrigation and having enhanced flexibility. Such fluidic connectors may have advantages over prior art dressings which may be more rigid and therefore uncomfortable for a patient, particularly when inserted into or located around sensitive wound areas. Other advantages may be that the fluidic connectors described herein are less prone to obstruction than the more rigid conduits of the prior art. Also disclosed are improved methods of use and systems for use of the same, preferably in conjunction with negative pressure wound therapy. 
         [0010]    In one embodiment, a fluidic connector for providing aspiration and irrigation to a wound site, comprises:
       a proximal end and a distal end and an elongate length extending therebetween;   a top layer, a bottom layer and an intermediate layer each constructed from a flexible, liquid impermeable material and adhered to one another, wherein each of the layers has a proximal end and a distal end and elongate portions extending therebetween;   an upper fluid passage between the top layer and the intermediate layer;   a lower fluid passage between the intermediate layer and the bottom layer;   one or more openings at or near a distal end of the upper fluid passage; and   one or more openings at or near a distal end of the lower fluid passage;   wherein each of the upper and lower fluid passages comprises a flexible, elongate spacer material between corresponding layers; and   wherein one of the upper and lower fluid passages is configured to provide aspiration to the wound site, and the other of the upper and lower fluid passages is configured to provide irrigation fluid to the wound site.       
 
         [0019]    In further embodiments, the spacer material of each of the upper and lower fluid passages may comprise at least one of a 3D knitted or 3D fabric material, foam, a porous material and non-woven material. The upper fluid passage configured to provide aspiration to the wound and the lower fluid passage may also be configured to provide irrigation fluid to the wound. The one or more openings at or near a distal end of the upper fluid passage may comprise an upwardly facing opening in the top layer. The one or more openings at or near a distal end of the upper fluid passage may comprise a distally facing opening between the top and intermediate layers. The spacer material of the upper fluid passage may extend distally beyond the distally facing opening between the top and intermediate layers. The one or more openings at or near a distal end of the lower fluid passage may comprise a plurality of microporous openings in the bottom layer. Some embodiments can further comprise a fluid distributing layer positioned below the one or more openings at or near a distal end of the lower fluid passage. A distal end of the spacer material of the lower fluid passage may extend distally beyond a distal end of the spacer material of the upper fluid passage. 
         [0020]    In further embodiments, the fluid passage configured to provide irrigation fluid to the wound site may comprise a plurality of radially extending arms at a distal end thereof. Some embodiments may comprise plurality of openings along each of the radially extending arms. The radially extending arms may comprise spacer material therein. The radially extending arms may be formed in part by the bottom layer. The radially extending arms may be part of a manifold attached to the bottom layer with the radially extending arms in fluid communication with the one or more openings at or near the distal end of the lower fluid passage. 
         [0021]    Some embodiments may further comprise adhesive along at least a portion of the bottom layer for adhering the bottom layer to skin adjacent a wound. The corresponding layers of each of the upper and lower fluid passages may have side portions along sides of the elongate spacer material that are parallel to and adhered to each other. The fluidic connector is sufficiently soft to conform to a patient&#39;s skin along a substantial portion of a length of the fluidic connector. 
         [0022]    In another embodiment, a method of treating a wound of a patient, comprises:
       positioning the fluidic connector of any one of the preceding claims into a wound with the one or more openings of the upper and lower fluid passages positioned within the wound and the proximal end of the fluidic connector positioned outside of the wound with a portion of the fluidic connector positioned against the skin of the patient;   covering the wound with a wound cover, wherein the wound cover is sealed to skin surrounding the wound and seals against the portion of the fluidic connector positioned against the skin of the patient;   providing negative pressure to the wound through one of the upper and lower fluid passages; and   providing irrigation fluid to the wound through the other of the upper and lower fluid passages.       
 
         [0027]    Further embodiments may further comprise positioning a porous wound filler into contact with the wound, and positioning the distal end of the fluidic connector over the porous wound filler. Some embodiments may further comprise positioning a porous wound filler over the distal end of the fluidic connector, and positioning the wound cover over the porous wound filler that is positioned over the distal end of the fluidic connector. 
         [0028]    In another embodiment, a system for treatment of a wound comprises:
       a sealing membrane for covering the wound;   a dressing adapted to be positioned in the wound; and   a fluidic connector capable of being operably associated, in use, with the wound cavity, the fluidic connector comprising:
           a proximal end and a distal end and an elongate length extending therebetween;   a first layer of flexible film,   a second layer of flexible film sealed around a perimeter to the first layer of flexible film, thereby defining an aspirant channel, wherein at least one aspiration opening in the distal end of the first layer of flexible film is configured to transmit aspiration to the wound cavity, and   a third layer of flexible film sealed around a perimeter to the second layer of flexible film, thereby defining an irrigation channel, wherein at least one irrigation opening in the distal end of the third layer is configured to transmit irrigation fluid to the wound.   
               
 
         [0036]    In further embodiments, each of the aspirant channel and irrigation channel may comprise a flexible, elongate spacer material between corresponding layers. The spacer material may extend through the at least one aspiration opening. 
         [0037]    In further embodiments, an aspirant conduit may be provided at the proximal end of the aspirant channel. A vacuum means may be configured to apply negative pressure to the wound through the aspirant conduit and the aspirant channel. A waste collection canister may be configured to connect to a proximal end of the aspirant conduit. An irrigation conduit may be provided at the proximal end of the irrigation channel. An irrigation source may be configured to provide irrigation fluid to the wound through the irrigation conduit and the irrigation channel. 
         [0038]    Further embodiments may comprise a manifold attached over the at least one irrigation orifice, the manifold having a lower surface, the manifold adapted to deliver irrigation fluid across a larger area than the distal end of the irrigation opening. The manifold may comprise a plurality of radially extending arms. Each of the plurality of radially extending arms may comprise a plurality of irrigation orifices in the lower surface. The wound filler may comprise first and second layers of a wound filling material, and wherein the distal end of the fluidic connector is positioned between the first and second layers of wound filling material. 
         [0039]    In another embodiment, a fluidic connector for providing aspiration and irrigation to a wound site, may comprise:
       a top layer and a bottom layer each constructed from a flexible, liquid impermeable material, wherein each of the layers has a proximal end and a distal end and elongate portions extending therebetween, and wherein each of the layers has a left edge and a right edge and a center portion therebetween;   a left seal extending along the length of the left edges of the top and bottom layers, a right seal extending along the length of the right edges of the top and bottom layers, and a middle seal extending along at least a portion of the length of the center portions of the top and bottom layers;   a left fluid passage between the top and bottom layers, further defined by the left seal and the middle seal;   a right fluid passage between the top and bottom layers, further defined by the middle seal and the right seal;   one or more openings in the bottom layer at or near a distal end of the left and right fluid passages; and   at least one applicator portion attached to or integral with the bottom layer at a distal end of the bottom layer;   wherein each of the left and right fluid passages comprises a flexible, elongate spacer material between the top and bottom layers; and   wherein one of the left and right fluid passages is configured to provide aspiration to the wound site, and the other of the left and right fluid passages is configured to provide irrigation fluid to the wound site.       
 
         [0048]    In another embodiment, a fluidic connector for providing aspiration and irrigation to a wound site, may comprise:
       a proximal end and a distal end and an elongate length extending therebetween;   a first fluid passage and a second fluid passage positioned side-by-side and joined together along at least a portion of the elongate length, each of the fluid passages containing an elongate spacer material; and   at least one applicator portion at the distal end;   wherein the first fluid passage is configured to provide aspiration to a wound site, and the second fluid passage is configured to provide irrigation fluid to the wound site.       
 
         [0053]    In further embodiments, the first fluid passage and the second fluid passage may be separated at the distal end, each fluid passage being connected to a separate applicator portion. The first fluid passage and the second fluid passage may be formed between flexible layers of liquid impermeable material. 
         [0054]    In another embodiment, a method of treating a wound of a patient, may comprise:
       positioning a wound cover over a wound, wherein the wound cover seals to skin surrounding the wound;   positioning a fluidic connector as described above over an opening in the wound cover;   providing negative pressure to the wound through one of the fluid passages; and   providing irrigation fluid to the wound through the other of the fluid passages.       
 
         [0059]    In another embodiment, a system for treatment of a wound, may comprise:
       a sealing membrane for covering the wound;   a wound filler adapted to be positioned in the wound; and   a fluidic connector as described above configured to be sealed over an opening in the sealing membrane.       
 
         [0063]    Further embodiments may comprise a source of negative pressure configured to be in fluid communication with one of the fluid passages, and a source of irrigation fluid configured to be in fluid communication with the other of the fluid passages. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0064]      FIG. 1A  illustrates an embodiment of a negative pressure wound treatment system capable of aspirating and irrigating a wound; 
           [0065]      FIG. 1B  illustrates an embodiment of a negative pressure wound treatment system capable of aspirating and irrigating a wound; 
           [0066]      FIG. 2  illustrates a cross sectional view of an embodiment of a fluidic connector for irrigation and aspiration used with a negative pressure wound treatment system; 
           [0067]      FIG. 3A  illustrates a top view of an embodiment of a fluidic connector for irrigation and aspiration of wounds; 
           [0068]      FIG. 3B  illustrates a bottom view of an embodiment of a fluidic connector for irrigation and aspiration of wounds; 
           [0069]      FIG. 3C  illustrates an exploded view of the layers of an embodiment of a fluidic connector for irrigation and aspiration of wounds; 
           [0070]      FIG. 3D  illustrates an exploded view of the layers of an embodiment of a fluidic connector with an integrated manifold; 
           [0071]      FIG. 3E  illustrates a cross sectional view of one end of an embodiment of a fluidic connector for irrigation and aspiration of wounds; 
           [0072]      FIG. 4A  illustrates a top view of an embodiment of a manifold for use with an irrigation fluidic connector; 
           [0073]      FIG. 4B  illustrates a bottom view of an embodiment of a manifold for use with an irrigation fluidic connector; 
           [0074]      FIG. 5A  illustrates a top view of an embodiment of a manifold attached to a fluidic connector for irrigation and aspiration of wounds; 
           [0075]      FIG. 5B  illustrates a bottom view of an embodiment of a manifold attached to a fluidic connector for irrigation and aspiration of wounds; 
           [0076]      FIG. 5C  illustrates a cross sectional side view of a manifold attached to a fluidic connector for irrigation and aspiration of wounds; 
           [0077]      FIG. 6  illustrates a cross sectional view of an embodiment of a fluidic connector for irrigation and aspiration of wounds having a flat lower layer; 
           [0078]      FIG. 7  illustrates an embodiment of a fluidic connector for irrigation and aspiration of wounds having the layers sealed in the middle of the height of the fluidic connector; and 
           [0079]      FIGS. 8A-D  illustrate various views of an embodiment of a fluidic connector for irrigation and aspiration of wounds having side-by-side channels. 
       
    
    
     DETAILED DESCRIPTION 
       [0080]    Preferred embodiments disclosed herein relate to wound therapy for a human or animal body. Therefore, any reference to a wound herein can refer to a wound on a human or animal body, and any reference to a body herein can refer to a human or animal body. The term “wound” as used herein, in addition to having its broad ordinary meaning, includes any body part of a patient that may be treated using negative pressure. Wounds include, but are not limited to, open wounds, incisions, lacerations, abrasions, contusions, burns, diabetic ulcers, pressure ulcers, stoma, surgical wounds, trauma and venous ulcers or the like. Treatment of such wounds can be performed using negative pressure wound therapy, wherein a reduced or negative pressure can be applied to the wound to facilitate and promote healing of the wound. It will also be appreciated that the negative pressure systems and methods as disclosed herein may be applied to other parts of the body, and are not necessarily limited to treatment of wounds. 
         [0081]    With reference initially to  FIGS. 1A-B , treatment of a wound in certain embodiments of the application uses a system  100  comprising a therapy unit  110 , a fluidic connector  125  having an elongate bridge portion  130  extending between a proximal end  145  and a distal end  150 , a manifold  140  at the distal end  150 , a wound filler  160  and a drape  170 . A single conduit  120  ( FIG. 1A ) or multiple conduits  122 ,  124  ( FIG. 1B ) may be utilized to connect the fluidic connector  125  to the therapy unit  110 . 
         [0082]    The wound may be filled with a filling or packing material  160 . Suitable materials for the wound filler  160  may be porous, pressure resistant materials which resists crushing at negative pressures of a maximum of about −250 mmHg below atmospheric, and materials which may also serve to maintain a uniform pressure distribution over the area of the wound. Such materials are known to those skilled in the art and may include Gazetex™ gauze bandage roll supplied by Derma Sciences Inc., CAVICARE™ supplied by Smith &amp; Nephew, open cell reticulated polyurethane foam, polyvinyl alcohol foam, Mepitel™ supplied by Molnlycke, or compressed foam, for example. As described further below, multiple wound fillers may be used, for example a first wound filler that is placed in contact with the wound and a second wound filler that may be placed over the fluidic connector  125 . 
         [0083]    In some embodiments, as illustrated in  FIG. 1A , the fluidic connector  125  may be configured to be placed in the wound, either above and/or under one or more wound fillers  160 . As described in further detail below, the fluidic connector  125  is configured to provide deliver both aspiration and irrigation to the wound. As illustrated, a conduit  120  with at least two interior channels or lumens (one for aspiration, one for irrigation) may connect the proximal end of the elongate bridge  130  of the fluidic connector to an integrated therapy unit  110 . The integrated therapy unit  110  may contain means for providing negative pressure, such as a vacuum pump, and means for supplying irrigation fluid. For example, an integrated unit could be an irrigation and aspiration unit such as Ulta™ supplied by KCl. In other embodiments, separate irrigation and aspiration units may be provided. 
         [0084]    Over the wound filler  160  and fluidic connector  125  is the drape  170 . The drape  170  may be a flexible film, for example polyurethane. With the elongate bridge  130  of the fluidic connector  125  positioned against the skin surrounding the wound, the drape  170  may be laid over the wound and sealed to the patient&#39;s healthy skin surrounding the wound, creating a substantially sealed wound cavity to which negative pressure may be transmitted. The drape  170  is therefore also laid over the elongate bridge  130  of the fluidic connector  125 , forming a seal with an upper surface of the elongate bridge as well as the skin on both sides of the elongate bridge. In some embodiments, a lower surface of the fluidic connector  125  may also be sealed to the patient&#39;s skin. For example, adhesive may be applied under the fluidic connector  125  prior to placement of the connector over the patient&#39;s healthy skin, or may be provided along the elongate bridge  130  during manufacture and protected prior to use by a release layer. The drape  170  and/or fluidic connector  125  may be effectively sealed to the patient&#39;s healthy skin surrounding the wound by means of an adhesive on the wound-facing lower surface of the drape, for example a pressure-sensitive adhesive. However, the term “sealed” is not an absolute requirement nor practically attainable since many flexible drape membrane materials are composed of semi-permeable plastics materials which are well known to those skilled in the art. The term semi-permeable is defined as being permeable to water vapour and gases but not liquids or air, having a transmissibility of moisture vapour greater than approximately 500 g/sq·m/per 24 hr period. Furthermore, there is almost inevitably some leakage between the skin to which the sealing drape is adhered due to hairs and/or other skin surface irregularities and/or imperfections which are not easily completely sealed in absolute terms. Examples of the types of self-adhesive, flexible dressing drape materials which are ordinarily used in TNP type therapy as sealing membranes over and around wounds are listed hereinabove and are well known to those skilled in the art and will not be elaborated on further herein unless necessary. 
         [0085]    Some embodiments may employ separate units for irrigation and aspiration, as illustrated in  FIG. 1B . For example, an aspirant conduit  122  may enable fluid communication between the proximal end of the fluidic connector  125  and a pump  104  for generating aspiration at the wound site. Liquid comprising wound exudate and/or irrigation fluid may be carried away from the wound through the aspirant conduit  122 . A waste canister  102  may optionally be disposed between the fluidic connector  130  and the pump  104  for collection of fluid, for example irrigation fluid and wound exudates, which has been removed from the wound site. In some embodiments, the canister  102  may be integrated into the pump  104 . However, in other embodiments, the wound filler  160  may act as a waste canister to collect and store wound exudate removed from a wound site beneath the drape  170 . 
         [0086]    An irrigation conduit  124  may enable fluid communication between the proximal end of the fluidic connector  125  and an irrigation source  106 . Irrigation fluid from the irrigation source may be drawn into the wound using the same pump  104  that provides aspiration through conduit  122 , or a separate irrigation pump may also be used. Further arrangements for providing aspiration and irrigation to the wound, as well as other systems, apparatuses and methods that may be incorporated with the features described herein, are described in U.S. Pat. Nos. 7,524,315 and 8,105,295, the entireties of each of which are hereby incorporated by reference. 
         [0087]      FIG. 2  illustrates a cross sectional view of a wound site  200  comprising a wound cavity  210  packed with a first wound filling layer  162 , above which is located a fluidic connector  125  similar to what&#39;s shown in  FIG. 1A . The fluidic connector comprises an irrigation manifold  140  located at a distal end  150  of an elongate bridge  130 , wherein the elongate bridge  130  comprises an irrigation channel  132  and an aspiration channel  134 . As illustrated and as further described below, in some embodiments the aspiration channel is an upper channel above a lower irrigation channel, though in other embodiments this arrangement can be reversed, or the channels could be side-by-side. A second wound filling layer  164  is positioned above the fluidic connector and the cavity  210  is sealed with a flexible drape  170 . With the elongate bridge of the fluidic connector  125  positioned against the skin surrounding the wound, the drape  170  may be laid over the wound and the elongate bridge, and may be sealed to the upper surface and sides of the elongate bridge and the patient&#39;s healthy skin surrounding the wound, for example by means of a pressures sensitive adhesive provided on the lower (wound facing) surface of the drape. Sealing the drape to the bridge and the healthy skin may create a substantially sealed wound cavity to which negative pressure may be transmitted. In other embodiments, the drape may comprise an upper layer and a lower layer, and the fluidic connector may extend between the upper and lower layers. 
         [0088]    As illustrated the wound may be filled with two layers of packing material  162 ,  164 , and the distal end  150  of the fluidic connector and the manifold  140  may be disposed between the two layers. The manifold  140  may be in fluid communication with the irrigation channel  132  at the distal end  150  of the elongate bridge  130 , and as illustrated may be provided below the irrigation channel  132  to distribute irrigation fluid to the wound. However, in some embodiments such as shown in  FIGS. 3A-3C  described below, the distal end  150  of the fluidic connector may be adapted to provide irrigation fluid to the cavity  210 , and the lower manifold may be optionally not included. The lower surface of the fluidic connector distal end  150  or manifold  140  may provide irrigation fluid through at least one orifice by means of irrigation channel  132 , as described further below. 
         [0089]    Using irrigation fluid that passes through the irrigation channel  132 , the lower wound filler  162  in contact with the wound cavity surface  210  may be irrigated with fluid beneficial for the healing process. Negative pressure may be applied to the wound site through the aspiration channel  132  and distributed through the upper wound filler  164  which may substantially fill the wound. In some embodiments, the lower wound filling layer  162  may be a thin sheet shaped to line the wound surface, and the upper wound filling layer  164  may be shaped to maintain a substantially flat surface approximately level with the patient&#39;s healthy skin when the wound cavity is under negative pressure. In some embodiments, as described further below, the wound site may be aspirated through at least one orifice at the distal end of the fluidic connector  150 . 
         [0090]    The drape  170  may be placed over the bridge portion  130  and substantially seal to the top surface and sides of the bridge portion and the exposed healthy skin of the patient. The drape may seal, for example, by a pressure-sensitive adhesive provided on the lower surface of the drape. The substantially sealed drape  170  and wound cavity surface  210  define a wound cavity which may be provided with negative pressure. 
         [0091]      FIGS. 3A-C  illustrate an embodiment of a fluidic connector  300  which may be used in the systems of  FIGS. 1A-B  and for treatment of a wound cavity such as in  FIG. 2 . In these embodiments, the fluidic connector does not have a separate manifold such as manifold  140  described above.  FIG. 3A  illustrates a top view of the fluidic connector  300 ,  FIG. 3B  illustrates a bottom view of the fluidic connector  300 , and  FIG. 3C  illustrates an exploded view of the fluidic connector  300 . 
         [0092]    The fluidic connector  300  may comprise an elongate bridge portion  310  and an enlarged rounded (e.g. circular) end  320 . The distal end of the fluidic connector is depicted as having an enlarged circular shape, although it will be appreciated that any suitable shape may be used and that the distal end need not be enlarged. The fluidic connector  300  may comprise a sealed perimeter  330  defining one or more fluid transmission channels. 
         [0093]    The fluidic connector  300  may comprise multiple layers of a flexible film material sealed to one another in a perimeter  330 . As shown in  FIG. 3C , a three layer structure may be provided, comprising a bottom layer  334 , an intermediate layer  333 , and a top layer  332  to form an upper fluid passage and a lower fluid passage. Each of these layers may be made of a flexible film, and in some embodiments may be transparent. Some embodiments of the flexible film may be formed from a soft polymer, for example a polyethylene, a polyvinyl chloride, a silicone or polyurethane having a hardness of 30 to 90 on the Shore A scale. 
         [0094]    At the distal end of the fluidic connector, the top layer may have an opening  352  through which aspiration to the wound can be provided. Also at the distal end of the fluidic connector, the bottom layer may have one or more openings  354  for providing irrigation to the wound. In certain embodiments, the lower surface of the enlarged end  320  of the lower film layer  334  may be provided with an adhesive for attaching to a manifold, as described below, or simply for attaching the lower surface to skin surrounding the wound. 
         [0095]    The top, intermediate, and bottom film layers  332 ,  333 ,  334  may be substantially the same shape as one another, and may each comprise an elongate bridge portion and an enlarged (e.g., rounded or circular) portion at a distal end thereof. Alternatively, the layers need not have the same shape, and in one embodiment, the intermediate and bottom layers may have a larger distal end than the top layer to provide a greater area to distribute irrigation to the wound. 
         [0096]    The top layer  332  may be sealed to one or both of the intermediate layer  333  and the bottom later  334 , for example by heat welding, radio frequency welding, laser welding, or ultrasonic welding. In some embodiments, the bottom layer  334  may be substantially flat and the top layer  332  and intermediate layer  333  may be slightly larger than the bottom layer  334  in order to accommodate the height of the spacer layers (described below) and seal to the bottom layer. Such an arrangement is also shown with respect to  FIG. 6 . In other embodiments, the top layer  332  and bottom layer  334  may be substantially the same size and may be slightly larger than the intermediate layer  333 , and the layers may be sealed together approximately at the middle of the height of the fluidic connector  300  such that the intermediate layer  333  is substantially flat. Such an arrangement is also shown with respect to  FIG. 7 . 
         [0097]    In some embodiments, the elongate bridge portions of the film layers may have a length of 10 cm (or about 10 cm) or more, more preferably a length of 20 cm (or about 20 cm) or more and in some embodiments, may be about 69 cm (or 27 cm) long. Some embodiments of the entire fluidic connector, from a proximalmost edge of the top and bottom layers to a distalmost edge of the top and bottom layers, may be between 20 cm and 80 cm (or about 20 cm to about 80 cm) long, more preferably about 60 cm and 80 cm (or between about 60 cm and about 80 cm) long, for example about 70 cm long. In some embodiments, the elongate bridge portion of the flexible film layers may have a width of between 1 cm and 4 cm (or between about 1 cm and about 4 cm), and in one embodiment, is about 2.5 cm wide. The ratio of the length of the elongate bridge portion to the width may in some embodiments exceed 6:1, and may more preferably exceed 8:1 or even 10:1. The diameter of the circular portion may be about 3.5 cm in some embodiments, or may be much larger to better distribute aspiration and irrigation to the wound. 
         [0098]    The fluidic connector may comprise a first spacer layer  342  and second spacer layer  344 , the first spacer 342 layer positioned between the top layer  332  and the intermediate layer  333  and the second spacer layer  344  positioned between the intermediate layer  333  and the bottom layer  334 . In some embodiments, the first spacer layer may be used as an aspirant layer and the lower spacer layer may be used to transmit irrigation fluid. The aspirant spacer layer  342  may optionally comprise a hole  353  located beneath the hole  352  in the top film layer  332  to facilitate transmission of negative pressure. 
         [0099]    The spacer layers may be made of any suitable material, for example material resistant to collapsing in at least one direction, thereby enabling effective transmission of negative pressure or irrigation fluid therethrough. In particular, the spacer layers ensure that an open channel can be maintained to communicate negative pressure or irrigation fluid through the fluidic connector  300  to the wound area. The spacer layer  342  should remain open under the typical pressures that will be applied during negative pressure wound therapy. The spacer layers are preferably formed of a material having a three dimensional structure. For example, a knitted or woven spacer fabric (for example Baltex  7970  weft knitted polyester) or a non-woven fabric could be used. The spacer layers may also comprise materials such foams, including open-cell foams such as polyethylene or polyurethane foam, meshes, non-woven materials, and fluid channels. 
         [0100]    In some embodiments, each of the spacer layers  342 ,  344  may comprise a 3D polyester spacer fabric layer including a top layer (that is to say, a layer distal from the wound-bed in use) which is a 84/144 textured polyester, and a bottom layer (that is to say, a layer which lies proximate to the wound bed in use) which is a 10 denier flat polyester and a third layer formed sandwiched between these two layers which is a region defined by a knitted polyester viscose, cellulose or the like monofilament fiber. Other materials and other linear mass densities of fiber could of course be used. 
         [0101]    Some embodiments of the fluidic connector  300  may employ the same fabric for both the upper and lower spacer layers  342 ,  344 . However, in other embodiments, a first material may be used as a spacer layer for the aspirant channel and a second material may be used as a spacer layer for the irrigation channel, the first and second materials having properties optimized for the purpose of aspiration or irrigation, respectively. Alternatively, some embodiments may utilize spacer fabric only for the aspirant channel so that the channel remains open even under negative pressure, and the irrigation channel may simply comprise a fluid passage encapsulated by the surrounding film layers. 
         [0102]    Although the illustrated embodiment has been generally described as having an upper aspirant channel and a lower irrigation channel, it will be appreciated that many variations of this configuration are possible. For example, some embodiments may employ more than two fluid transmission channels. Other embodiments may only employ an irrigation channel. In some embodiments the fluid transmission channels may be side by side, or the irrigation channel may be above the aspirant channel. 
         [0103]    In some embodiments, the elongated bridge of the spacer layers  342 ,  344  may have dimensions in the same ranges as the bridge portions of the film layers described above though slightly smaller, and in one embodiment is about 25.5 cm long and about 1.5 cm wide. Similarly, the diameter of the enlarged distal portion  320  of the spacer layers may be slightly smaller than the diameters of the enlarged ends of the film layers, and in one embodiment is about 2 cm. Some embodiments of a spacer layer may have adhesive on one or both of its proximal and distal ends (e.g., one or more dabs of adhesive) in order to secure the spacer layer to one or both of the adjacent film layers. Adhesive may also be provided along a portion or the entire length of one or both of the spacer layers. In other embodiments, one or both of the spacer layers may be freely movable within the sealed chamber of the adjacent film layers. 
         [0104]    Some embodiments may optionally comprise a first conduit  362  and a second conduit  364  at the proximal end of the elongate bridge portion  310  of the fluidic connector  300 . In some embodiments, the first conduit  362  may be in fluid communication with spacer layer  342 , and may transmit fluid including irrigation fluid and wound exudates away from a wound site through orifice  352 , as well as providing negative pressure to the wound site. The second conduit  364  may be in fluid communication with spacer layer  344 , and may transmit irrigation fluid through a plurality of holes  354  located in the lower film layer  334 . In some embodiments, an optional fluid distributing layer  355  can be positioned below the plurality of holes  354  in the lower film layer  334  to aid in even distribution of fluid across part of all of a wound site. For example, fluid distributing layer  355  can be a perforated film or microporous layer such as polyurethane foamed film or compressed foam. Fluid distributing layer  355  can be welded to, glued to, or laminated over the lower surface of the lower film layer  334  below the plurality of holes  354  in various embodiments. In some embodiments, fluid distributing layer  355  can be pre-attached to the lower surface of the lower film layer  334 . In other embodiments, the fluid distributing layer  355  can be positioned between the lower surface of the lower film layer  334  and a wound to be treated. As described above, in other embodiments such as shown in  FIG. 1A , a single conduit having multiple lumens may also be utilized to transmit negative pressure and deliver irrigation fluid to the fluidic connector  300 . 
         [0105]      FIG. 3D  illustrates an embodiment of a fluidic connector  300  in which the two layers of flexible film of the manifold  370  form part of the intermediate layer  333  and bottom layer  334 . Thus, the intermediate layer  333  and bottom layer  334  are shaped such that a manifold  370  is simply a part of the fluidic connector. The manifold top layer  372  is formed by the distal end of the intermediate layer  333 , the manifold spacer material  373  is formed by the distal end of the spacer layer  344 , and the manifold bottom layer  374  is formed by the distal end of the bottom layer  334 . A plurality of pores  375  may be provided in the lower manifold layer  374  for distribution of irrigation fluids. The pores  375  may cover substantially all of the surface of the manifold layer  374 . In such embodiments, the spacer material  373  in the manifold may also be part of the spacer material  344  of  FIG. 3C . The manifold portion  373  of the spacer layer  334  extends distally past the end of the upper spacer layer  342 . In the illustrated embodiment, the manifold top layer  372 , manifold spacer material  373 , and manifold bottom layer  374  are integrally formed as extensions of the intermediate film layer  333 , spacer layer  344 , and lower film layer  334  of the elongate bridge portion  310 , respectively. However, in other embodiments the manifold  370  may be a separate structure attachable to a lower surface of the bottom film layer  334  of the elongate bridge portion  310 , for example by adhesive or welding. 
         [0106]      FIG. 3E  illustrates a cross sectional view of one example arrangement of the conduits and flexible film layers at the proximal end of the elongate bridge portion  310  of the fluidic connector  300 . As illustrated, the intermediate film layer  333  is positioned underneath the first conduit  362  and above the second conduit  364 , however this can be reversed in other embodiments. Accordingly, the first conduit  362  and the second conduit  364  are positioned in a side-by-side configuration. The lower film layer  334  is positioned underneath the intermediate film layer  333  under the first conduit  362  and underneath the second conduit  364 . The upper film layer  332  is positioned above the first conduit  362  and above the intermediate film layer  333  above the second conduit  364 . Such a side-by-side configuration of the conduits  362 ,  364  can reduce the height of the fluidic connector compared to an arrangement in which conduits  362 ,  364  are positioned above and below one another. Although the conduits  362 ,  364  are arranged in a side-by-side configuration, the upper spacer layer  342  and lower spacer layer  344  with which conduits  362 ,  364  (respectively) are in fluid communication can remain positioned above and below one another. 
         [0107]      FIGS. 4A-4B  illustrate top and bottom views of an embodiment of a manifold  400  attachable to a fluidic connector, such as described in  FIGS. 3A-C , or that may be incorporated as part of the fluidic connector. The manifold may advantageously distribute the irrigation fluid over a larger area than the enlarged end of the fluidic connector. The manifold may comprise a plurality of radially extending arms  410 . In some embodiments, the arms  410  may be sized larger than a wound such that they may be made to fit the wound by folding the arms  410  back on themselves. Other embodiments of the manifold may employ a variety of other suitable shapes, including shapes with more or less radially extending arms, circular shapes, etc. 
         [0108]    The manifold may comprise two layers of a flexible film such as used for the fluidic connector described above, wherein the layers are sealed around a perimeter. The encapsulated inner area of the manifold may contain a layer of spacer fabric or other spacer material. Suitable materials include those discussed above as well as reticulated filtration polyurethane foams with small apertures or pores. The top film layer of the manifold may be provided with a hole  420  for accepting irrigation fluid from the fluidic connector. The hole  420  may communicate with the plurality of holes  354  of the fluidic connector  300 , or may communicate with a single larger hole at the enlarged end of the bottom layer of the fluidic connector  300 . 
         [0109]    As shown in  FIG. 4B , some embodiments of the manifold may comprise an array of holes  430  provided through the lower layer of the manifold for outlet of irrigation fluid. Other embodiments may utilize different configurations of holes than the illustrated embodiment, or may employ a porous membrane as the lower surface. For example, in some embodiments the holes  430 , or pores or micropores used instead of or in addition to the holes  430 , may cover substantially all of the area of the radially extending arms  410 . In some embodiments the holes  430 , or pores or micropores used instead of or in addition to the holes  430 , may be arranged in regions of the radially extending arms  410  or in patterns over a portion of the area of the radially extending arms  410 . 
         [0110]    The holes or pores of the manifold may be sized or otherwise configured in some embodiments so as to limit the maximum pressure at which irrigation fluid may be delivered to a wound. The pores may also be sized such that, at the desired flow rate, the fluid passes out of the manifold uniformly across its entire area, ensuring that the wound is uniformly irrigated. For example, some embodiments may limit the pressure of the fluid to approximately eight to twelve pounds per square inch. This may be advantageous as fluids delivered at high pressures may disturb the healing wound bed, and if the pressure exceeds approximately 15 psi, bacteria may be pushed further into a patient&#39;s wound. In other embodiments the irrigation fluid supply flow regulation may be accomplished by other means, such as a pump and/or feed pressure. 
         [0111]      FIG. 5A  illustrates a top view of an embodiment of the fluidic connector  300  of  FIGS. 3A-C  attached to the manifold  400  of  FIGS. 4A-B . The upper layer of the fluidic connector  300  has an orifice  352  for providing aspiration through the upper channel of the fluidic connector and for drawing fluid away from a wound.  FIG. 5B  illustrates a bottom view the fluidic connector  300  attached to the manifold  400 . The lower layer of the manifold is provided with a plurality of orifices  430  for transmitting irrigation fluid to the wound. Some embodiments may employ very fine pore size foams for the lower layer, for example materials felted by heat and compression to produce a dense, porous film. The manifold may be attached to the fluidic connector during manufacture of the fluidic connector, such that the manifold is simply part of the fluidic connector. Alternatively, the manifold may be provided to a user separately from the fluidic connector and may be attached to the fluidic connector by the user. This may be advantageous to allow the user to select different manifolds depending on the needs of the patient. 
         [0112]      FIG. 5C  illustrates a cross sectional side view of another embodiment of the fluidic connector  300  having a manifold  400 . The upper film layer  440  and lower perforated film layer  460  of the manifold  400  are illustrated, encapsulating spacer layer  450 . In the embodiment illustrated, a portion  390  of the spacer fabric of the aspirant channel may extend beyond the orifice in the top layer, advantageously reducing the possibility of occlusion of the orifice  352 . In such an embodiment, the distal end of the fluidic connector has a distally facing opening to transmit negative pressure to the wound. 
         [0113]      FIG. 6  illustrates a cross sectional view of the elongated length of an embodiment of a fluidic connector  600  having a substantially flat lower film layer  650 , a lower spacer layer  640 , an intermediate film layer  630 , an upper spacer layer  620 , and an upper film layer  610 . The upper and intermediate film layers  610 ,  630  are sealed together or welded along a perimeter  660  such that the intermediate film layer  630  is slightly larger than the lower film layer  650  to accommodate the height of lower spacer layer  640 , and the upper film layer  610  is slightly larger than the intermediate film layer  630  to accommodate the heights of both spacer layers as well as the height of the intermediate layer. 
         [0114]      FIG. 7  illustrates a cross sectional view of the elongated length of an embodiment of a fluidic connector  700  having a lower film layer  750 , a lower spacer layer  740 , a substantially flat intermediate film layer  730 , an upper spacer layer  720 , and an upper film layer  710 . The upper and intermediate film layers  710 ,  730  are sealed together or welded along a perimeter  760  such that the upper film layer  710  is slightly larger than the intermediate film layer  750  to accommodate the height of the upper spacer layer  720 . In a substantially symmetrical configuration, the lower and intermediate film layers  750 ,  730  are adhered along a perimeter  760  such that the lower film layer  750  is slightly larger than the intermediate film layer  750  to accommodate the height of the lower spacer layer  740 . 
         [0115]    Advantageously, in the embodiments of  FIGS. 6 and 7 , the corresponding layers of each of the upper and lower fluid passages have side portions along sides of the elongate spacer material that are parallel to and adhered to each other. This gives the fluidic connector a flatter cross-sectional profile that decreases in dimension towards both side edges to facilitate sealing of a drape over the fluidic connector. Because the spacer material between the corresponding layers is flexible, the fluidic connector is relatively soft, and is capable of conforming to the contours of a patient&#39;s skin. 
         [0116]      FIGS. 8A-D  illustrate various views of an embodiment of a fluidic connector  800  for irrigation and aspiration of wounds having side-by-side channels  802 ,  803 . As shown in the partial cross-sectional view of  FIG. 8A , a flexible drape  820  such as those discussed above may be substantially sealed to the healthy skin of a patient surrounding a wound bed  840 . The wound bed  840  may contain a wound filler  830 , such as foam or gauze or other suitable material. In contrast to some of the embodiments described above, the fluidic connector  800  may be secured over at least one opening or orifice  810  in drape  820  to provide the wound cavity  840  with irrigation and negative pressure. The orifice  810  may be pre-made in the drape, or may be made by the health practitioner. The fluidic connector  800  comprises an applicator portion  806  that may be secured over the orifice  810  in the drape  820 , and a flexible, elongate bridge portion  801  to connect the drape to sources of negative pressure and irrigation fluid, as described below. The elongate bridge portion may optionally be sealed to the drape and/or skin surrounding the wound using a suitable adhesive. 
         [0117]      FIG. 8B  illustrates a cross-sectional view of the fluidic connector  800  taken along a portion of the elongate bridge portion  801 . The fluidic connector  800  may comprise a top layer  814  and a bottom layer  815 , which may comprise flexible, liquid impermeable flexible films, such as polyurethane. The top and bottom layers  814 ,  815  may be sealed around a perimeter  817  of the fluidic connector, for example by heat welding. Extending along at least a portion of the length of the fluidic connector is middle separation portion  816 , which creates a right channel  803  and a left channel  802  in the sealed top and bottom layers. Though the middle separation  816  is depicted at the center of the width of the fluidic connector, thus creating two equally sized right and left channels, it will be appreciated that in some embodiments the middle separation may be located more to one side or the other, thereby creating a right and left channel of different sizes. In some embodiments, the middle separation  816  may be a weld between the top and bottom layers. In other embodiments, the middle separation may be a vertically-extending layer connected at its lower end to the bottom layer  815  and at its upper end to the top layer  814 . 
         [0118]    The right and left channels shown in  FIG. 8B  each contain an elongate spacer material  812 ,  813 . In some embodiments these may be the same material, while in other embodiments they may comprise different materials. For example, in one embodiment the spacer material  813  of the left channel  802  may comprise 3D fabric for transmission of negative pressure and aspiration of exudate, while the spacer material  812  of the right channel  803  may comprise open celled foam for transmission of irrigation fluid. In other embodiments the left channel  802  may be used for irrigation and comprise foam as the spacer material  813 , and the right channel  803  may be used for aspiration and comprise 3D fabric as the spacer material  812 . Other suitable materials for the spacer material are described with respect to the previous embodiments above. 
         [0119]    As illustrated in  FIG. 8C , the side-by-side channels  802 ,  803  may be joined along a right side of the left channel  802  and a left side of the right channel  803  for the entire length of the fluidic connector  800 . Some embodiments may form both channels out of two flexible film layers with a middle seal between the two layers used to separate the channels, for example a heat weld which runs down the center of the two layers as described above. The side-by-side channels  802 ,  803  may be connected to a single applicator flange portion  806 . The applicator flange portion  806  may be secured to a lower surface of the distal end of the fluidic connector (e.g., secured to bottom layer  815 ), for example by heat welding or adhesive. In some embodiments, the applicator flange portion may merely be an extension of a lower layer (e.g., bottom layer  815 ) of the side-by-side channels  802 ,  803 . The applicator flange portion  806  may be a layer of flexible film, and may have a pressure-sensitive adhesive provided on the lower surface thereof for sealing the fluidic connector  800  to a drape  820 . In some embodiments, the adhesive layer may be protected prior to use by a removable protective layer (not illustrated) which may be peeled off to expose the adhesive. Each of the side-by-side channels  802 ,  803  may have an orifice  804 ,  805  located on the lower surface of a distal end thereof for delivery of fluid or aspiration through the at least one orifice  810  in the drape  820 . The applicator flange portion  806  may have a hole or holes which correspond to the orifices  804 , 805 . In some embodiments, each of the channel orifices  804 ,  805  may be located over a separate orifice in the drape  820 . 
         [0120]    As illustrated by  FIG. 8D , the side-by-side channels  802 ,  803  may be joined along a right side of the left channel  802  and a left side of the right channel  803  for only a portion of the length of the fluidic connector  800 , and then may separate and connect to two separate applicator flange portions  806 . Although the separated fluidic connector is depicted as a “Y” shape, it will be appreciated that many configurations are possible, for example one channel may remain straight while the other is bent. Some embodiments of the fluidic connector may be formed with a separated portion as illustrated, while some embodiments may be formed fully joined and may be separated as needed for use, for example by being pulled apart for the desired length. 
         [0121]    One of the side-by-side channels  802 ,  803  may provide irrigation fluid to the wound. The other of the side-by-side channels  802 ,  803  may transmit negative pressure to the wound as well as aspirate fluid, which may comprise irrigation fluid and wound exudate, away from the wound. In some embodiments, the channels may be used simultaneously. In other embodiments, use of the channels may be alternated. For example, negative pressure may be provided to the wound cavity through the aspirant channel, and the wound may continue to receive negative pressure therapy for a first period of time. Irrigation fluid may then be provided to the wound through the irrigation channel and may be allowed to sit in the wound for a second period of time. After the second period of time, the aspirant channel may then be used to remove the irrigation fluid (and any wound exudate) and again initiate negative pressure in the wound cavity. This cycle may be repeated as needed, and it will be appreciated that although the example given began with a period of negative pressure, either negative pressure or irrigation may be used for the first cycle. This cyclic irrigation/aspiration process may be useful for bolus irrigation. 
         [0122]    Additionally, some embodiments of the above-described aspiration and irrigation conduits may provide a means for venting air or a pressure monitoring line. For example, some embodiments may include a vent hole in the top layer of one of the two channels of the fluidic connector, for example at the proximal end of the elongate bridge. Other embodiments employ a third conduit or vent channel in the elongate bridge portion, the third conduit in fluid communication with a vent orifice. The vent orifice may be at the proximate end of the bridge portion, and may be provided with a filter. The vent channel may be provided with a spacer fabric, such as any of the spacer fabrics described above. Other embodiments may accomplish venting by means of a standalone vent port over a hole in the sealing drape. 
         [0123]    In some embodiments, the third conduit or vent channel may be used as a separate pressure monitoring conduit. In other embodiments, the third conduit may be used to alternately vent and measure pressure. The conduit may switch between venting and pressure monitoring at regular intervals, or may switch in a controlled manner based on one or more parameters of the negative pressure system. In embodiments which alternate venting and pressure monitoring, air may be vented into to the wound for a first specified time period, for example via a valve attached to the third conduit; the valve may then be closed, thus preventing air from entering the negative pressure system and a pressure reading may be taken, for example via a pressure sensor fluidically attached to the third conduit. Once a stable pressure reading has been measured, or after a second specified period of time has passed, the valve may be opened and the cycle repeated. In some embodiments, the first specified time period may be 1-600 seconds, or approximately 1 to approximately 600 seconds, and the second specified time period may be 0.1-60 seconds, or approximately 0.1 second to approximately 60 seconds. Vent flows may be of the order 0.1 to 10 liters per minute, or approximately 0.1 to approximately 10 liters per minute. The addition of a vent may advantageously help to stabilize the pressure at the wound by minimizing the amount of liquid present in the main aspirant conduit and reducing the possibility of blockage formation. 
         [0124]    Features, materials, characteristics, or groups described in conjunction with a particular aspect, embodiment, or example are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. The protection is not restricted to the details of any foregoing embodiments. The protection extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed. 
         [0125]    While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of protection. Indeed, the novel methods and systems described herein may be embodied in a variety of other forms. Furthermore, various omissions, substitutions and changes in the form of the methods and systems described herein may be made. Those skilled in the art will appreciate that in some embodiments, the actual steps taken in the processes illustrated and/or disclosed may differ from those shown in the figures. Depending on the embodiment, certain of the steps described above may be removed, others may be added. Furthermore, the features and attributes of the specific embodiments disclosed above may be combined in different ways to form additional embodiments, all of which fall within the scope of the present disclosure. 
         [0126]    Although the present disclosure includes certain embodiments, examples and applications, it will be understood by those skilled in the art that the present disclosure extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses and obvious modifications and equivalents thereof, including embodiments which do not provide all of the features and advantages set forth herein. Accordingly, the scope of the present disclosure is not intended to be limited by the specific disclosures of preferred embodiments herein, and may be defined by claims as presented herein or as presented in the future.