Abstract:
A tourniquet cuff ( 10 ) includes a first layer ( 20 ), a second layer ( 40 ), and a third layer ( 60 ). The first layer ( 20 ) has an inner side ( 22 ) impermeable to air and the second layer ( 40 ) has a first side ( 44 ) impermeable to air. The inner side ( 22 ) of the first layer ( 20 ) and the first side ( 44 ) of the second layer ( 40 ) cooperate to define a first cavity ( 96 ) formed to receive a gel-like material ( 15 ) therein. Further, the third layer ( 60 ) has an inner side ( 64 ) which cooperates with a second side ( 42 ) of the second layer ( 40 ) to define a second cavity ( 94 ) formed to receive pressurized air. The tourniquet cuff ( 10 ) adjustably secures about a patient&#39;s limb such that the gel-like material ( 15 ) is positioned between the patient&#39;s limb and the second cavity ( 94 ) to uniformly and comfortably distribute pressure around the patient&#39;s limb.

Description:
GEL TOURNIQUET CUFF 
     This application is a continuation-in-part of U.S. application Ser. No. 09/467,521, filed Dec. 21, 1999, now abandonded, which claims priority under U.S.C. §119(e) to U.S. Provisional Application No. 60/114,726, filed Dec. 31, 1998, which is expressly incorporated by reference herein. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a tourniquet cuff and particularly to a tourniquet cuff for providing uniform pressure distribution and patient comfort. 
     BACKGROUND AND SUMMARY OF THE INVENTION 
     Tourniquet cuffs are used to reduce the flow of blood to a location on the human body where surgery is taking place. Typically, tourniquet cuffs employ a cotton layer which wraps around the patient&#39;s arm or leg at a point proximal to the heart from where surgery is being performed. During use, the cotton layer is positioned adjacent to the patient&#39;s limb. An expandable air bladder surrounds the cotton layer to allow various pressures to be applied to the cotton layer, and thus, to the patient&#39;s limb. By providing pressure around a patient&#39;s limb, the tourniquet cuff reduces the flow of blood to that portion of the limb distal to the tourniquet cuff and toward the limb&#39;s extremity. The cotton layer is employed so that the tourniquet cuff may be placed comfortably on the patient&#39;s limb. 
     According to one embodiment of the present invention, a tourniquet cuff is provided to distribute pressure more evenly and for better patient comfort than is provided by traditional tourniquet cuffs. The tourniquet cuff of the present invention includes a gel layer within the tourniquet cuff. Adjacent to the gel layer is an air bladder which is inflated to provide pressure around a patient&#39;s limb. As an alternative to an air bladder, other devices, such as a simple strap, may be used to provide pressure around the patient&#39;s limb. During use, the air bladder is inflated around the patient&#39;s limb with the gel layer positioned between the patient&#39;s limb and the air bladder. The gel layer conforms to the particular patient&#39;s limb for added comfort and better pressure distribution than may be provided by traditional tourniquet cuffs. Another object of the present invention is to provide a funnel-shaped (tapered) section at one end of the tourniquet to allow the tourniquet to resist folding and buckling and to allow the tourniquet to conform more comfortably to the patient&#39;s limb. 
     In a preferred embodiment, a length of polyester nap material and two lengths of nylon material are positioned in layers and sealed together at their perimeters to create two bladders and define two air-tight chambers—a first chamber between the polyester nap layer and the middle nylon layer and a second chamber between the middle nylon layer and the outer nylon layer. A gel-like material is positioned within the first chamber and the second chamber can be inflated to provide increased pressure to a patient&#39;s limb when the tourniquet is around the patient&#39;s limb. 
     The polyester nap material and the top nylon layer each have a tapered portion, one coupled to the other, each having a wide end and a narrow end, the wide end of the polyester nap material and the wide end of the top nylon layer being coupled to one end of the two bladders. A VELCRO loop-portion strap is coupled to the narrow end of the polyester nap material and to the narrow end of the top nylon layer. A VELCRO hook-portion strap is attached to the top surface of the second chamber for securing the tourniquet cuff about the patient&#39;s limb. 
     In yet another embodiment, a length of polyester nap material and a first length of nylon material are positioned in layers and sealed together at their perimeters to create a first chamber. A gel-like material is positioned within the first chamber. A second length and a third length of nylon material of substantially the same dimensions as the first chamber are positioned in layers and sealed together at their perimeters and also lengthwise down their approximate middles to create second and third parallel airtight chambers. The second and the third chambers can be inflated independently of each other to provide increased pressure to a patient&#39;s limb when the tourniquet is around the patient&#39;s limb. 
     In yet a further embodiment, an elongated chamber is wrapped and fastened about a patient&#39;s limb and inflated to apply pressure to the limb and reduce or eliminate blood flow. An additional chamber is secured to the inflatable chamber to extend therealong and to be disposed between the inflatable chamber and the surface of the patient&#39;s limb. A gel-like substance is disposed within the additional chamber to distribute pressure uniformly and comfortably on the patient&#39;s limb. 
     Additional features and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description exemplifying the best mode of carrying out the invention as presently perceived. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the gel tourniquet cuff in accordance with the present invention; 
     FIG. 2 is a sectional view of the tourniquet of FIG. 1 taken along line  2 — 2 ; 
     FIG. 3 is a sectional view similar to that shown in FIG. 2 illustrating an additional embodiment of the present invention; 
     FIG. 4 is a sectional view of a bladder port of the tourniquet of FIG. 1 taken along the line  4 — 4 ; 
     FIG. 5 is a plan view of one end of the tourniquet of FIG. 1, showing a VELCRO loop portion coupled to a polyester nap funnel-shaped end of the tourniquet; 
     FIG. 6 is a perspective view showing another embodiment of the gel tourniquet cuff in accordance with the present invention; 
     FIG. 7 is a sectional view of the tourniquet of FIG. 6; and 
     FIG. 8 is a sectional view similar to that shown in FIG. 7 illustrating an additional embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION 
     Tourniquet cuff  10 , shown in FIG. 1, includes a polyester nap layer  20 , an outer nylon layer  60 , a VELCRO hook-portion  80 , a VELCRO loop-portion  90 , a polyurethane bladder port  100  (best seen in FIG.  4 ), a PVC tube  110  (best seen in FIG.  4 ), and a tie  120  having first and second tie ends  121 ,  122 . Polyester nap layer  20  and outer nylon layer  60  are generally rectangular in shape except for a polyester nap funnel-shaped end  21  (FIG. 5) and an outer nylon funnel-shaped end  61 , including a funnel perimeter  76 . 
     Referring now to FIGS. 1,  2 , and  5 , polyester nap layer  20  includes a first nap side  22 , a second nap side  24 , and first, second, and third nap fold portions  27 ,  28 , and  29  folded along first, second, and third nap folds  30 ,  31 , and  32 . Further, polyester nap layer  20  includes a nap-funnel boundary  25  and a nap perimeter portion  35  located adjacent first, second, and third nap folds  30 ,  31 ,  32 , a nap funnel boundary  25 , and a funnel-shaped end  21 . For patient comfort, polyester nap layer  20  may have a felt-like texture which remains exposed on second nap side  24 . However, first nap side  22  may be coated with a thin (illustratively 4 mil) layer of polyurethane  26  to produce a surface impervious to the gel-like material  15  (best seen in FIG.  2 ). It is understood that within the scope of this disclosure, materials other than polyurethane may be used to form such an impervious surface. Also, other materials, including soft cotton and other comfortable materials, may be used for polyester nap layer  20 . 
     As best seen in FIG. 2, adjacent to polyester nap layer  20  is a middle nylon layer  40 , including a first middle nylon side  42 , a second middle nylon side  44 , a first middle nylon edge  47 , and a second middle nylon edge  48 . As best seen in FIG. 1, middle nylon layer  40  also includes a third middle nylon edge  49 , a fourth middle nylon edge  50 , and a middle nylon perimeter portion  55  located adjacent to the first, second, third, and fourth middle nylon edges  47 ,  48 ,  49  and  50 . First middle nylon side  42  and second middle nylon side  44  are preferably coated with thin (illustratively 4 mil) layers of polyurethane to produce air-impenetrable surfaces. Again, it is understood that materials other than polyurethane may be used to form such air-impenetrable surfaces and that materials other than polyurethane-coated nylon may be used for the middle nylon layer. Middle nylon layer  40  is the same, generally rectangular, shape as polyester nap layer  20  and outer nylon layer  60 , except that, as shown, middle nylon layer  40  does not include a funnel-shaped end. However, to provide additional structural support, middle nylon layer  40  may be provided with a funnel-shaped end similar to funnel-shaped end  21 . Further, in the illustrative embodiment, middle nylon layer  40  is slightly smaller than polyester nap layer  20 , so that when second middle nylon side  44  is positioned adjacent first nap side  22  and outer nylon layer  60  is positioned adjacent to middle nylon layer  40 , first, second and third nap fold portions  27 ,  28 ,  29  extend beyond first, second, and third middle nylon edges  47 ,  48 ,  49  and polyester nap funnel-shaped end  21  extends beyond fourth middle nylon edge  50 . As discussed below, this arrangement aids in the formation of tourniquet cuff  10  of the preferred embodiment. 
     Preferably, middle nylon layer  40  is a fairly stiff material, having a denier greater than 200. In a preferred embodiment, middle nylon layer  40  is approximately a 420 denier nylon material. Such a material provides sufficient stiffness to prevent the tourniquet cuff  10  from rolling down the patient&#39;s limb, while providing enough flexibility to allow for satisfactory pressure distribution characteristics. 
     As shown in FIGS. 1 and 2, adjacent to middle nylon layer  40  is outer nylon layer  60 , which includes a main outer nylon body  65 , a first outer nylon side  62 , a second outer nylon side  64 , a first outer nylon edge  68 , a second outer nylon edge  69 , and a third outer nylon edge  70 . Further, outer nylon layer  60  includes an outer nylon funnel boundary  66  between main outer body  65  and outer nylon funnel-shaped end  61 , and an outer perimeter portion  75  located adjacent first, second, and third outer nylon edges  68 ,  69 , and  70  and outer nylon funnel boundary  66  (best seen in FIG.  1 ). As with sides  22 ,  42 , and  44 , second outer nylon side  64  is preferably coated with a thin (illustratively 4 mil) layer of polyurethane to produce an air-impenetrable surface, but it is understood that materials other than polyurethane may be used to form such an air-impenetrable surface. As illustrated, outer nylon layer  60  is the same, generally rectangular, shape as polyester nap layer  20 , including outer nylon funnel-shaped end  61 , which is the same general shape and size as polyester nap funnel-shaped end  21 . However, as with middle nylon layer  40 , outer nylon layer  60  is slightly narrower and shorter than polyester nap layer  20 , so that first, second, and third nap fold portions  27 ,  28 ,  29  extend beyond first, second, and third outer nylon edges  68 ,  69 , and  70 . Lastly, an aperture  63  is formed in outer nylon layer  60  (best seen in FIG.  4 ). 
     Referring to FIGS. 1 and 4, polyurethane bladder port  100  includes a bladder flange  101  and a bladder nozzle  102 . As illustrated, bladder nozzle  102  is inserted through aperture  63  in outer nylon layer  60  so that bladder flange  101  abuts second outer nylon side  64 . Bladder flange  101  is affixed to second outer nylon side  64 , coupling bladder port  100  to outer nylon layer  60 . As best seen in FIGS. 1,  2 , and  4 , with bladder port  100  coupled to outer nylon layer  60 , second outer nylon side  64  is positioned adjacent first middle nylon side  42  so that first, second, and third middle nylon edges  47 ,  48 ,  49  line up with first, second, and third outer nylon edges  68 ,  69 ,  70 , and outer perimeter portion  75  is positioned adjacent middle nylon perimeter portion  55 . First nap side  22  is then positioned adjacent second middle nylon side  44  so that first, second, and third nap folds  30 ,  31 ,  32  line up with first, second, and third middle nylon edges  47 ,  48 ,  49 , and first, second, and third outer nylon edges  68 ,  69 ,  70 . Thus, nap perimeter portion  35  is positioned adjacent middle nylon perimeter portion  55 . Therefore, in the illustrated embodiment, middle nylon layer  40  is sandwiched between polyester nap layer  20  and outer nylon layer  60 . With the three layers  20 ,  40 , and  60  in position, heat and pressure is applied to nap perimeter portion  35 , middle nylon perimeter portion  55 , and outer nylon perimeter portion  75  simultaneously, creating a heat seal  85  binding the three layers  20 ,  40 , and  60  together. However, it is understood that other methods of binding the layers together are possible within the scope of this invention. Further, heat seal  85  is air-impenetrable so that an air chamber  94  is created between first middle nylon side  42  and second outer nylon side  64 . Bladder port  100  provides an opening  92  (best seen in FIG. 4) defining a passageway  93  into air chamber  94 . However, other than opening  92 , air chamber  94  is air-tight. Heat seal  85  also creates a gel chamber  96  between first nap side  22  and second middle nylon side  44 . Prior to binding layers  20 ,  40 , and  60  together, a gel-like material  15  is positioned within gel chamber  96 . Therefore, when layers  20 ,  40 , and  60  are bound together, gel-like material  15  is sealed within gel chamber  96 . 
     In an alternative embodiment of the tourniquet cuff  200  (FIG.  3 ), the middle nylon layer  40  of FIG. 2 is replaced by multiple layers  240  and  245 , one cooperating with polyester nap layer  20  to create gel chamber  96  and another cooperating with outer nylon layer  60  to create air chamber  94 . Also, in another alternative embodiment, gel-like material  15  is pre-sealed within its own flexible packaging (not shown), and the entire gel-like material package is shaped and positioned within gel chamber  96 . In this embodiment, gel chamber  96  need not be sealed, thus allowing easy removal and replacement of the gel-like material package. 
     In a further embodiment, as shown in FIGS. 6 and 7, a gel-like material  315  is used in a tourniquet cuff  310  of a Bier&#39;s Block design, in which the tourniquet has a first air bladder  394  having a first bladder port  302  and a second air bladder  398  having a second bladder port  301 , wherein the first and second air bladders  394 ,  398  are placed in a side-by-side arrangement. Adjacent to first air bladder  394  is placed a first gel cavity  396  with gel-like material  315  disposed therein. Likewise, adjacent to second air bladder  398  is placed a second gel cavity  399  with gel-like material  315  disposed within. It is understood within the scope of this disclosure that the gel-like material in first gel cavity  394  need not be the same as gel-like material in the second gel cavity  396 . An inflation device  311 , as is known in the art, may be used to inflate air bladders  394  and  398 , via first and second bladder ports  302  and  301 . 
     The embodiment illustrated in FIG. 6 is provided with a pair of straps,  390  and  391 . As contemplated in this embodiment, each strap would be provided with a fastener, such as VELCRO hook sections, for mating with the VELCRO loop sections  380  and  381 . However, it is understood that, rather than straps  390  and  391 , the funnel-shaped design best illustrated in FIGS. 1 and 5 could be used with the Bier&#39;s Block tourniquet design of FIG.  6 . 
     In still another embodiment, a tourniquet  400  (FIG. 8) is provided with first and second gel cavities  396  and  399  (shown in FIG. 7) are replaced by a single gel cavity  496 . As with the embodiments described in FIGS. 6 and 7, the gel-like material  415  is placed between air bladders  394  and  398  and the patient&#39;s limb. 
     Referring back to FIGS. 1,  2 ,  4 , and  5 , once polyester nap layer  20 , middle nylon layer  40 , and outer nylon layer  60  have been heat-sealed together, first nap fold portion  27 , second nap fold portion  28 , and third nap fold portion  29  are folded over first outer nylon side  62  along first, second, and third nap folds  30 ,  31 , and  32 , respectively. Once nap fold portions  27 ,  28 ,  29  are folded over first outer nylon side  62 , it is preferred that nap fold portions  27 ,  28 ,  29  are sewn through heat seal  85  with a stitching  86 . Other methods of affixing nap fold portions  27 ,  28 ,  29  may be used. 
     As best seen in FIGS. 1 and 5, a first end  91  of VELCRO loop-portion  90  is secured between outer nylon funnel-shaped end  61  of outer nylon layer  60  and polyester nap funnel-shaped end  21  of polyester nap layer  20 . Illustratively, stitching  86  continues from nap fold portions  27 ,  28 ,  29 , as well as along the funnel perimeter  76  of outer nylon funnel-shaped end  61  and polyester nap funnel-shaped end  21 , thereby coupling outer nylon funnel-shaped end  61 , polyester nap funnel-shaped end  21  and end  91  of VELCRO loop-portion  90 . Alternatively, VELCRO loop portion  90  may be an extension of polyester nap funnel-shaped end  21  or outer nylon funnel-shaped end  61 . Fixed to main outer nylon body  65  on first outer nylon side  62  is a length of VELCRO hook-portion  80 . Tie  120  is fixed to first and second nap fold portions  27  and  28  adjacent and parallel to third nap fold portion  29 . Lastly, PVC tube  110  includes a first PVC end  111  fixed to bladder nozzle  102  and a second PVC end  112  fixed to a connector  113 . Preferably, connector  113  is an easy-lock connector, as is known in the art. However, other connectors are within the scope of this invention. An inflation device  11  provides a means for inflating air chamber  94  with air or another pressurized fluid. 
     During use, tourniquet cuff  10  is wrapped around a patient&#39;s limb, with polyester nap layer  20  adjacent the patient&#39;s limb, so that VELCRO loop-portion  90  engages VELCRO hook-portion  80  securing tourniquet cuff  10  to the patient&#39;s limb. Optionally, tie ends  121 ,  122  of tie  120  are then tied together so that tie  120  is secured around VELCRO loop-portion  90 . Air chamber  94  is then be inflated by pumping air through PVC tube  110 , through passageway  93  in bladder port  100 , and into air chamber  94 . With tourniquet cuff  10  wrapped around the patient&#39;s limb, gel chamber  96  is positioned between air chamber  94  and the patient&#39;s limb. Therefore, when air is pumped into air chamber  94 , pressure is exerted around gel chamber  96  which, in turn, transmits pressure around the patient&#39;s limb. While VELCRO is utilized in the preferred embodiment, other fasteners, including straps, buckles, snaps, and tape, may be used to secure the tourniquet around a patent&#39;s limb. 
     The gel-like material may be any suitable material that will uniformly distribute the pressure on the patient&#39;s limb. Such materials include FLOAM, manufactured by TekSource, Inc. in Draper, UT, FLO-LITE, manufactured by Alden Laboratories, Inc. in Boulder, Colo., and ISOGEL, manufactured by Pittsburgh Plastics, Inc. in Zelienople, Pa. It is understood, however, that the use of other materials would be obvious to one with ordinary skill in the art. 
     Although the invention has been described in detail with reference to preferred embodiments, variations and modifications exist within the scope and spirit of the invention as described and defined in the following claims.