Patent Publication Number: US-2016220322-A1

Title: Fluid collection apparatus

Description:
CLAIM OF PRIORITY 
     This patent application is a continuation of and claims the benefit of priority under 35 U.S.C. §120 to U.S. patent application Ser. No. 13/663,252, filed on Oct. 29, 2012, which claims the benefit of priority of U.S. Provisional Patent Application Ser. No. 61/552,254, filed on Oct. 27, 2011, which is incorporated by reference herein in its entirety. 
    
    
     BACKGROUND 
     The present invention relates generally to methods and apparatus for collecting fluids during surgical procedures; and more particularly relates to such methods and apparatus particularly adapted for surgeries on a patient&#39;s joint. 
     While the inventive fluid collection methods and apparatus can be used with many forms of orthopedic surgery, the present disclosure primarily addresses the use of such methods and apparatus in an example application that can particularly benefit from the teachings herein, surgery on the knee, of which one common example is arthroscopic surgery on the knee. 
     As of the present time, many surgeries on joints are performed arthroscopically. The most common joints subject to such surgery include the knee, elbow, shoulder wrist, foot, ankle and hip. In such surgeries, typically an arthroscope is inserted into the joint through one small incision, and surgical instruments are inserted through a second incision. In most cases, an optic fluid is employed to continuously flush the joint while it is being examined and operated upon. The fluid used in such surgery must exit the body, and typically exits from one of the incisions made to conduct the surgery. It then drips or flows down the exterior of the joint, where it must be collected in order to maintain a clean, sanitary, and functioning surgical area. 
     To this end, various arthroscopy fluid pouches have been developed wherein the fluid drips or flows into the pouch from the joint, and the fluid is then suctioned from the bottom of the pouch through an exit port or nipple connected to a hose which in turn is connection to a suction pump. In many cases, these arthroscopy fluid pouches are integrated with a surgical drape that, in conjunction with an integrated fluid pouch, provides a fluid barrier around the joint and a collection area for the fluids. 
     Many forms of these pouches have been developed over the years to address the difficulties of such fluid collection during surgery, but these conventional arthroscopy fluid pouches still suffer from one or more deficiencies in actual use. One common problem with such pouches in knee surgery, for example, is that they inhibit movement of the limb during the surgery. Another problem of many of these pouches is that they can get pinched, folded, or re-shaped during surgery so that they less efficiently perform their fluid collection function, and can permit fluid to spill over the top perimeters of such pouches and create messy, or unsanitary, or otherwise undesirable conditions for the surgery. Another problem found with some prior art fluid collection pouches intended for use in surgery on the knee is that they are designed for use, or are more efficacious for use, when a patient undergoing the arthroscopic knee surgery is positioned so that their lower leg hangs off of the end of the operating table, such as the position depicted in  FIG. 1  of U.S. Pat. No. 4,974,604. However, today, many surgeons prefer to conduct such surgery with the patient in a supine position. The supine position exacerbates the aforementioned fluid collection problems, and the problems found in the pouches in the prior art. 
     SUMMARY OF THE INVENTION 
     The fluid collection pouches and surgical drapes in accordance with the present invention can include one or more multiple novel structures or features, as described herein. In many embodiments, the fluid collection pouches will be configured with an asymmetrical bottom contour to define a region of greater depth of the pouch beneath a patient&#39;s limb extending through the pouch on the lateral side of the limb than on the medial side. And in many embodiments, the fluid collection pouches will be configured with an asymmetrical top perimeter configured to define an upper surface with a region that extends at a greater height above a patient&#39;s limb extending through the pouch on the lateral side of the limb than on the medial side (when the patient and leg are in a supine position). In some of those embodiments, this region of greater height will be achieved by an extension region extending above the contours defining the majority of the surface defining the upper perimeter of the pouch. In some cases, this form of extension region will be implemented to provide an offset or discontinuity between portions at the upper (proximal) extent of the pouch. 
     In many embodiments, fluid collection pouches, and surgical drapes including such pouches, will preferably include a reinforcing member (or members) extending around the top perimeter of the fluid collection pouch. Preferably, the reinforcing member(s) will be encased retained within a sleeve, or otherwise bonded (such as by adhesive or some other form of attachment) proximate the upper perimeter of the pouch. In some examples, this reinforcing member will be pliable, and may be deformable, such as a metal wire or strap. The material for such a wire may be stainless steel, or another metal suitable for, and approved for, use in a sterile surgical environment. As will be apparent to those skilled in the art having the benefit of this disclosure, however, other types of material, such as flexible synthetic materials may be used to establish support and structure proximate the upper perimeter of the pouch. 
     In many embodiments, the surgical drape will be formed with a pouch which is asymmetrical relative to its placement on the patient&#39;s limb. Specifically, the portion of the pouch extending to the lateral, or “outside,” of the patient&#39;s limb (i.e., in the case of a knee, the portion of the pouch extending to the little toe side of the leg) will have a larger dimension than the portion extending to the opposite, relative “inside,” of the limb. Because this outside portion will typically be the lower side during the surgical operations, it is preferable to have a larger area to receive fluids, and thereby help avoid spillage of those fluids. 
     In some preferred embodiments, the upper perimeter will be formed with a discontinuity in what would otherwise represent a continuous curved elliptical shape. The discontinuity can serve to provide additional structure in support to the outer region of the pouch (as described in more detail below). In some embodiments, the top perimeter on the outer area of the pouch is lengthened and rejoined to the underlying surgical drape at a place above where the top perimeter of the inner area of the pouch joins the drape. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  depicts an example surgical drape including a fluid collection pouch in accordance with the present invention. 
         FIG. 2  depicts the surgical drape prototype of  FIG. 1  with the pouch in an opened state. 
         FIGS. 3A-B  depict the construction of the fluid collection pouch of the surgical drape of  FIGS. 1 and 2 ; wherein  FIG. 3A  depicts the pattern for the material used to form the fluid collection pouch in accordance with one method of manufacture of the pouch; while  FIG. 3B  depicts the resulting patterned sheet of material; 
         FIG. 4  depicts a surgical drape including a fluid collection pouch in an operating placement, disposed on a patient&#39;s leg while the knee is flexed with the patent in the supine position (thus, the foot will be on the underlying surgical table (not depicted)), as will typically occur during a surgical procedure. 
         FIG. 5  depicts the surgical drape placement of  FIG. 4  from an alternate view. 
     
    
    
     EXAMPLE EMBODIMENT 
     The fluid collection apparatus of the present invention can be adapted for any orthopedic surgery that would benefit from fluid collection. As noted earlier herein, one example environment in which the present methods and apparatus have particular applicability is that of arthroscopic surgery of the knee, and an example configuration for a surgical drape and associated fluid collection pouch for use in such surgery is described herein. Those skilled in the art will recognize that surgical drapes in accordance with the teachings herein may be adapted as necessary for use with other surgical procedures. Minor modifications to optimize the drape for such other procedures will be apparent to persons skilled in the art having the benefit of this disclosure. 
     In the description of the invention that follows, the use of the term “proximal” refers to being closer to the patient&#39;s torso, and the term “distal” refers to being closer to the patient&#39;s foot. The terms “outer” and “lateral” are used to refer to the outer side of the body or a limb thereof; for example, when referring to the leg, referring to the side of the leg bearing the little toe. Analogously, the terms “inner” and “medial” are used to refer to the inner side of the body or a limb thereof; for example, when referring to the leg, referring to the side of the leg bearing the big toe. These terms are consistent with common usage, such as reference to the “inner thigh” or “outer thigh.” 
     In one preferred implementation, the fluid collection apparatus of the present invention is implemented as a surgical drape, wherein the fluid collection pouch is formed in combination with surgical sheeting, which includes one or more layers of sheeting material. Alternatively, it would be possible for the described fluid collection pouch to be constructed and used as a separate component not physically attached to such sheeting. The sheeting material itself, exclusive of the pouch, will typically be formed of composite sheeting, which may be of any of multiple constructions known in the art. Additionally, such sheeting may not have a uniform cross-section across its entire dimension. For example, conventional surgical drapes will often include multiple layers in the sheeting closer to the surgical site, with one or more layers intended to repel fluids as well as one or more additional layers configured to absorb fluids that are not repelled. Additional sheeting layers may be present to optimize patient comfort and/or to assist in retaining surgical instruments. However, at locations remote from the surgical site, the sheeting may include a lesser number of layers, and potentially only a single layer. 
     Referring now to  FIGS. 1 and 2 , these Figures depict an example surgical drape  10 , including composite sheeting  14  and fluid collection pouch  12 . In  FIG. 1 , fluid collection pouch  12  is a generally folded position relative to composite sheeting  14 ; while in  FIG. 2 , fluid collection pouch  12  is opened somewhat to show the enclosure defined by fluid collection pouch  12 . The composite sheeting portion  14  of drape  10  includes at least three layers  16 ,  18 ,  20  that are bonded together in a conventional construction. The size and configuration of sheeting  14  may be of any configuration desired, from a simple rectangular shape to more complex patterns. 
     Fluid collection pouch  12  is formed of a material effectively impermeable to fluids of the type presented by surgery, such as polyethylene. Fluid collection pouch  12  is bonded with an aperture therein ( 42  in  FIG. 3B ) surrounding an aperture  22  in composite sheeting  14 , which allows passage of the patient&#39;s leg into the pouch. This bonding may be through use of a suitable adhesive, for example. Accordingly, in this embodiment one surface of pouch  12  becomes an integral portion of the sheeting portion  14  of drape  10 . 
     In some embodiments, the sheeting material defining the leg aperture  22  will be an elastomeric material that will engage a first location on the patient&#39;s leg, for example the thigh, to form a fluid dam, and may include cuffs or other edge finishing that assists in forming a fluid dam around the leg. In some alternate constructions the elastomeric material may be an insert  26  of elastomeric material attached to fluid collection pouch  12 , which is then attached to composite sheeting  14 . 
     Additionally, a second such insert  28  defining an aperture  46 , again preferably formed of an elastomeric material, is secured adjacent an aperture  44  in distal portion  30  of fluid collection pouch  12  to sealingly engage the patient&#39;s leg as it extends out through insert  28 . By this construction, the elastomeric material  46  surrounding and defining aperture  22 , as well as insert  28  defining aperture  44 , are each configured to sealingly engage a leg passing therethrough, to provide fluid isolation around the portion of the leg extending through collection pouch  12 , such that all fluids proximate the operating site are retained within pouch  12 . As will be apparent to those skilled in the art, a patient&#39;s leg will extend approximately along an axis  42  extending through apertures  22  and  46 . This axis  42  will be most apparent when the patient is in a supine position, with the knee unflexed. Axis  42  extends between and defines the medial and lateral sides of the patient&#39;s leg, and also of the fluid collection pouch (whether the pouch is in place on the patient or is separate therefrom). 
     Referring now particularly to  FIG. 2 , that figure illustrates fluid collection pouch  12  as it is been expanded from the folded or flat position of  FIG. 1  to a position approximating that it would have when in place on a patient&#39;s leg. Fluid collection pouch  12  includes a top perimeter  32 ; a continuous side portion, indicated generally at  34 ; and a bottom surface indicated generally at  39 . As noted above, a relatively proximal portion of the pouch, indicated generally at  36 , is bonded to composite sheeting  14  with an aperture therein ( 42  in  FIG. 3B ) surrounding aperture  22 , and forms a proximal portion  38  of the collection pouch  6 ; while an opposite portion of the pouch, indicated generally at  40 , forms a distal portion of the collection pouch  12 . Apertures  22  and  46 , in proximal portion  38  and distal portion  40 , respectively, are configured in a conventional manner to permit a human leg to pass therethrough, so that when in position, the knee is positioned within an area defined by top perimeter  32 . As described in more detail later herein, a substantial portion of top perimeter  32  of fluid collection pouch  12  will be supported by a structural element, preferably a deformable member. 
     Referring now to  FIGS. 3  A-B, these figures depict additional aspects of the construction of this example embodiment of fluid collection pouch  12 . Another feature of the depicted example embodiment is an asymmetrical curve to the bottom portion (or surface) ( 39  in  FIGS. 1 and 2 ) of fluid collection pouch  12 . In contrast to prior art structures, as described earlier, the depicted embodiment includes a structure providing the described asymmetrical curve to the bottom portion resulting in differing “depths” to the pouch along its length, with a greater depth and volume to the pouch on the distal side of a centerline through the pouch, when viewed in profile (such as a line extending across the knee and generally perpendicular to the knee); and this region of greater depth and volume will be on the lateral side of a patient&#39;s leg when in an operative placement on the patient. 
     This conformation can be seen in the pouch pattern  54  depicted in  FIG. 3A . The patterned sheet of material  52  of  FIG. 3B  formed from the pouch pattern  54  of  FIG. 3A , and further includes apertures  42 ,  44  through which a patient&#39;s leg will pass. Pouch pattern  54  includes the forms for two opposing surfaces  60 ,  62  of the pouch that will be formed by folding the patterned material relative to centerline  64  and bonding the then-aligning surfaces ( 66  and  68 ; and  70  and  72 ) to one another to form a receptacle and to thereby define the pouch. The patterned material surface corresponding to pattern surface  60  will be bonded to the drape to generally form the proximal surface of the drape which will extend around the thigh of the patient. The patterned material portion corresponding to pattern surface  62  will form the distal portion  40  of the pouch which will extend around the patient&#39;s lower leg. 
     Pouch pattern  54  clearly depicts the asymmetrical curve that will be applied to the patterned material by surfaces  70  and  72 . In this example, the surfaces  70 ,  72  defining the bottom contour of the pouch have a constantly varying radius along their entire length. In other examples utilizing an asymmetrical contour to define the pouch, some portion of the bottom contour might be linear or formed with a constant radius, with only a portion of the surface(s) defining the bottom contour of the pouch having a constantly varying radius. Alternatively, other configurations may be used to form a pouch that will have a depth below the patient&#39;s leg that expands in transition from the medial side of the leg axis ( 42  in  FIGS. 2 and 5 ). For example, such a bottom might have a region of a linear transition extending downwardly relative to the leg axis  42  as the surface extends from the medial side to the lateral side. 
     Referring again to the disclosed embodiment, the asymmetrical curve defined at  70  and  72  may be clearly seen by examining each profile between centerline  64  and the boundaries at  66  and  68  that will be bonded together to form the opposite extent (relative to centerline  36 ) of the completed pouch. The result of this configuration is that collection pouch  12 , when viewed in profile from a distal perspective (form the direction of the patient&#39;s feet), will have a bottom surface  36  with a shape defined by an arcuate surface with an increasing radius in the direction approaching the surfaces that define the relatively medial side of the pouch (i.e., towards lines  66  and  68 ), when in an intended operative placement. In other words, the shape is generally one of a French Curve, and thus has a shape generally comparable to that of the well-known Nike Swoosh™, as can be seen generally in  FIGS. 3A  and B. In more technical terms, the shape can generally be thought of as roughly comparable to the arc of a horizontal elliptical from a point approximating 70° to 250°. 
     As shown in  FIG. 3B , the exit port  76  is placed on the outer or lateral side and proximate the deepest portion of the pouch. The precise positioning of the exit port  76  provided will vary depending upon the precise configuration selected for bottom portion  12 . The objective of the positioning is to place exit port  76  on the outer (lateral) side of pouch  12 , which will be the lower side of the pouch during at least the majority of an arthroscopic procedure; and at a place along the curve that will be proximate the lowermost point of the bottom surface curve during the procedure. This conformation also improves drainage from the pouch relative to that experienced with at least some, if not all, prior art configurations. As will be apparent to those skilled in the art, a conventional port fitting (not illustrated) will be coupled proximate exit port  76  to facilitate coupling of a drain or suction hose to fluid collection pouch  12 . 
     As will be apparent to those skilled in the art, the specific shapes and dimensions of the surfaces defining fluid collection pouch  12  may be adapted to achieve a particular desired capacity and opening around the surgical site. In the disclosed embodiment, patterned material has a generally planar majority upper surface  89   a,    89   b , with an extension section extending therefrom. In this example, the extension section is in the form of an upwardly extending “fin” section, defined by a curvilinear surface  104  and a generally linear surface  106 . This fin section  102  will form the uppermost proximal extent of fluid collection pouch  12  on the lateral side of the patient&#39;s leg. Thus, when the patterned material is secured to the composite sheeting, as depicted in  FIGS. 1 and 2 , the portion having the fin section will be bonded to the sheeting, with the fin portion oriented to be on the lateral side of the patent&#39;s thigh. Thus, the material  52  in the depicted orientation is configured to be secured to sheeting material for use on a patient&#39;s left leg. If the pattern were turned over, then it would be positioned to be secured to underlying sheeting for use on a patient&#39;s right leg (as depicted in  FIGS. 1 and 2 ). 
     As one example construction, the patterned sheet of material  52  of  FIG. 3B  can have a total length  76  between approximately 44 and 50 inches. For an example with a length of approximately 50 inches, the following additional dimensions have been found to be satisfactory. A maximum depth  78  relative to top surface  89  of approximately 15.5 inches, with the “fin” section  102  having a height  80  relative to top surface  89  of approximately 7 inches, and a horizontal dimension (as depicted)  82  of approximately 9 inches. Apertures  42  and  44  can each be approximately 9 inches on each side; though in some embodiments, aperture  44  may be slightly smaller (for example, 8 inches in at least one dimension), since it needs to accommodate only the patient&#39;s calf, rather than the thigh. 
       FIG. 3B  also depicts placement of reinforcing members  108   a,    108   b , extending along nominal upper surfaces  89   a,    89   b,  and continuing along curvilinear surface  104  of fin section  102 . Reinforcing members  108   a,    108   b,  will preferably be coupled to one another proximate points  92  and  100 , to effectively form a single continuous reinforcing member  108 . In some embodiments, a single reinforcing member will be used and will be attached to the patented pouch material after it has been folded and bonded to form the pouch contour. Reinforcing member(s)  108  can be bonded (through adhesive or another process) to patterned material  52 ; and/or in some cases may be encased within a channel ( 112  in  FIGS. 4 and 5 ) in material  52 , as may be formed by folding over and sealing a flap of material  52  to surround reinforcing member(s)  108 . In currently preferred examples, when the material defining pouch  12  is secured to composite sheeting, the material will be bonded to the sheeting not only around aperture  42 , but also along at least a portion of fin section  102 , such as linear surface  106 , and along at least a portion of upper surface  89   a.    
     Reinforcing member  108  can also extend along the entire upper surface of the patterned material (i.e., also along linear portion  106  of fin section  102 , in the depicted example); though such is not needed, and in some processes may complicate the manufacturing process somewhat. As can be appreciated from review of  FIG. 3B  as well as  FIGS. 1 and 2 , the dimension of linear surface  106  of the “fin” portion  102  establishes a longitudinal offset between a first end of reinforcing member  108 , at location  98  (proximate the “top” of fin section  102 ), which will extend from the lateral side of the limb, relative to the second end of reinforcing member  108 , at location  98 , which will extend from the medial side of the limb. This longitudinal offset, which in this example will be proximally located adjacent the patient&#39;s thigh, provides the previously described greater depth and volume of fluid collection pouch  12  on the lateral side of the patient&#39;s leg, relative to the medial side. This discontinuity or offset in top perimeter  32  (adjacent surface  106  in the depicted example) is present whether or not reinforcing member  108  is continuous around top perimeter  32 . 
     As discussed above, the reinforcing member will be pliable, and preferably deformable, such that the material resists deformation of top perimeter  32 , but can be shaped deliberately by medical personnel as part of the surgery to hold a desired shape. A metallic wire, such as stainless steel wire, retained within channel ( 112  in  FIGS. 4 and 5 ) is one example of a desirable reinforcing member. For some examples, plastic coated wire of approximately 24 gauge has been found to be satisfactory. In some embodiments, it may be desirable to have a reinforcing member that offers greater resistance to deformation of top perimeter  32  in the distal portion  40  as compared to the top perimeter  32  in the proximal portion  38 . This non-uniform resistance to deformation around the periphery can be achieved by a variety of mechanisms, including having a reinforcing member or a reinforcing member assembly that is of a different material and/or dimension in distal portion  40  than in proximal portion  38 . Alternatively, multiple reinforcing members (such as, for example, multiple metal wires) might be used in distal portion  40 , with only a single reinforcing member placed in proximal portion  38 . However the reinforcing member is constructed, it will preferably be a continuous assembly from a first end at a relatively proximal position when in use (i.e., a “proximal end”) to a second end at a relatively distal position when in use (i.e., a “distal end”). 
     As depicted in  FIGS. 4 and 5 , those figures depict an example embodiment of a surgical drape as described herein, in position to fluidically isolate a patient&#39;s knee, such as for arthroscopic surgery on the knee. In these Figures, for clarity, only a portion of composite sheeting  14  is shown. To place the drape in position, the patient&#39;s foot of the patient is first passed through the opening  22  in the proximal portion and then the opening  44  in the distal portion. The drape is then moved further up the patient&#39;s leg, until the opening  22  in the proximal portion fits about the patient&#39;s thigh, and the opening  44  in the distal portion  30  fits about the patient&#39;s leg below the knee. The shaping of the pouch is assisted by deformable reinforcing member  108  secured proximate top perimeter  32 . 
     As noted above, some embodiments also rely on an upper perimeter that is discontinuous relative to a continuous elliptical curve, as depicted generally at  114 . This can be achieved by different mechanisms. For example, as depicted in the referenced figures, it can be seen that the top perimeter  32  of collection pouch  12  has a proximal end  116  and a relatively distal end  118  that do not join one another. In this example embodiment, this discontinuity is formed in part by surface  106  which extends between ends  116  and  118 . The relatively distal end  118  of top perimeter  32  of fluid collection pouch  12  is formed with distal region  40  of the fluid collection pouch; while proximal end  116  of top perimeter  32  of pouch  32  is formed with the proximal region  38  of fluid collection pouch  12 . Ends  116  and  118  are proximate one another adjacent the patients thigh, but are offset from one another by a short distance (preferably a few inches). Thus, the relatively proximal and distal ends  116 ,  118 , respectively, of top perimeter  32  will often essentially overlap one another proximate the patient&#39;s thigh. The overlapping structure is believed to give added strength to the outer (lateral) side of the collection pouch that is under the most stress during surgery. The overlapping section is also believed to reduce the risk of the collection pouch from failing by either collapsing or kinking during surgery. Thus the structure provides improved fluid collection and retention performance of fluid collection pouch  12 . In other embodiments, there may be a connection between the two sections of the pouch surface perimeter, and in such caases there will typically be a dogleg or other transition region between the arc of the perimeter of the lateral portion of pouch  12  (indicated generally at  120 ) relative to the arc of the perimeter of the medial portion (indicated generally at  122 ). 
     As noted above, in some embodiments, it will be desirable to have a greater volume of the pouch on the outer (lateral) side of the patient&#39;s leg, than on the inner (medial) side. Because that outer side will often be the lower side during certain stages of the surgical operations, a greater volume on this outer side will better facilitate capture and retention of fluids within the pouch. In the depicted example, this difference in volume is facilitated by the longer arc  120  of top perimeter  32  on the lateral side, proximally terminating at location  116 ; as compared to the shorter arc  122  on the medial side, terminating at location  118 . In this embodiment, the additional length of top perimeter  32  that ends at the proximal end portion  116  (attached to the sheet portion at a portion relatively proximal position, relative to the location  118  at which the distal portion of top perimeter  32  is attached to the sheet portion of the drape), helps provide stability to collection pouch  12 , such that during surgery applying pressure against collection pouch  12 , or the unintentional deformation of the collection pouch  12  will not readily lead to spillage or leakage of arthroscopy-related fluid as was the case with prior art designs. 
     In embodiments as depicted in the accompanying figures, which include both the unequal lengths to the outer and inner perimeters defining fluid collection pouch  12 ; and the asymmetrical shape of bottom portion  29 , those features enable pouch  12  to be shorter than pouches of conventional surgical drapes. 
     Many additional modifications and variations may be made in the techniques and structures described and illustrated herein without departing from the spirit and the scope of the present invention. Accordingly, the present invention should be clearly understood to be limited only by the scope of the claims and equivalents thereof.