Patent Publication Number: US-2012029406-A1

Title: Device and method for compressing wounds

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This is a continuation of application Ser. No. 12/489,799 filed Jun. 23, 2009, which is a continuation of application Ser. No. 11/043,350 filed Jan. 26, 2005, which is a continuation of application Ser. No. 10/397,785 filed Mar. 26, 2003, which claims the benefit of the filing date of U.S. Provisional Application No. 60/368,013 filed Mar. 27, 2002, the disclosures of which are hereby incorporated by reference herein. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates generally to a device and method for compressing a wound in a patient caused by any one of a number of medical procedures. In a particular embodiment, the present invention is directed to a device and method for compressing and sealing a puncture wound in a blood vessel of a patient caused by a medical procedure. 
     In certain medical procedures, such as cardiac catheterization, dilation and counterpulsation, a catheter or other device is inserted into an artery, most commonly by percutaneous methods, and then fed through the arterial tree to the site where needed, frequently, the region of the heart. The site usually selected for insertion is the groin because the femoral artery in that region is relatively easy to locate. 
     These procedures are normally initiated by insertion of an angiographic needle, followed by passing a guide wire through that needle into the artery. The needle is then removed, leaving the guide wire in place. Next, a sheath/dilator set is passed over the guide wire into the artery in order to enlarge the opening sufficiently to permit entry of the catheter or other device. The dilator is then removed, leaving the sheath or guide cannula in place. The catheter or other device can then be inserted through the cannula with full confidence that when it emerges from the distal end it will be within the lumen of the artery. 
     After a procedure, for example, counterpulsation, has been completed, the sheath must be removed and the wound closed. Often, this can be accomplished simply by the application of digital pressure, generally augmented by the use of a conventional pressure dressing, until hemostasis is achieved. Customarily, pressure must be applied for at least one half hour, and frequently for much longer than that. In addition, during this period the patient must be immobilized, lest movement interfere with the closing process. Because of the pressure required, the time during which it must be applied and the need for immobilization, the procedure is painful and uncomfortable. It also requires the prolonged personal attention of a health care professional. Finally, wound closures accomplished in this manner are prone to open unexpectedly long after closure appears to have been completed. Patients are therefore often required to maintain bedrest, oftentimes in the hospital, for 24 hours or longer. 
     In addition to the need for applied pressure to seal a puncture wound in an artery or blood vessel of a patient, there are other medical situations in which the application of pressure to a particular region of a patient&#39;s body is required. For example, there may be a requirement for pressure to stanch bleeding or reduce hematomas following biopsies, ambulatory dialysis, insertion of intravenous needles, emergency procedures and other such situations. 
     Although devices have been developed to address these situations, and particularly the difficulties associated with achieving hemostasis of an artery or blood vessel, these devices have met with various degrees of success and oftentimes create new difficulties. There therefore exists a need for a device for applying compression to wounds in patients which is inexpensive, effective, easy to use and comfortable for the patient, and which overcomes many of the drawbacks of the prior art devices. 
     SUMMARY OF THE INVENTION 
     The present invention addresses these needs. 
     One aspect of the present invention provides a dressing for applying compression to a wound in a patient. The dressing includes an inflatable bladder having a non-deformable end wall and a deformable membrane connected to the end wall so as to define an enclosed space therebetween. The bladder has a deflated condition in which the membrane is adjacent the end wall and an inflated condition in which the membrane is spaced from the end wall. Holding means are provided for holding the bladder against the skin of the patient in a position substantially overlying the wound without circumscribing the leg or torso of the patient. 
     The holding means may include a flexible web connected to the end wall of the bladder and projecting outwardly therefrom. The flexible web may extend radially outward in all directions from the bladder and may include a layer of adhesive on one surface for adhering the flexible web to the skin of the patient. 
     The bladder in the inflated condition may decrease in size in a direction away from the end wall. In preferred embodiments, the bladder in the inflated condition may have a frusto-conical or frusto-pyramidal shape. 
     The end wall may be formed from a rigid material, such as plastic, and may be transparent. The end wall may also be formed from the same material as the deformable membrane, and may be molded integrally with the deformable membrane. 
     Another aspect of the present invention provides a method of applying compression to a wound in a patient. The method includes providing a dressing including an inflatable bladder having a non-deformable end wall and a deformable membrane connected to the end wall so as to define an enclosed space therebetween; applying the dressing against the skin of the patient in a position substantially overlying the wound; inflating the bladder to an inflated condition, whereby the inflated bladder exerts pressure on the wound to reduce the flow of blood from the wound; and applying manual pressure to the dressing against the skin of the patient so as to achieve hemostasis of the wound. 
     The method may further include providing a flexible web connected to the end wall of the bladder, the flexible web having a layer of adhesive on one surface thereof, and adhering the flexible web to the patient&#39;s skin. 
     The bladder in the inflated condition may decrease in size in a direction away from the end wall. In preferred methods, the bladder in the inflated condition may have a frusto-conical or frusto-pyramidal shape. 
     The providing step may include providing the dressing such that the end wall and the deformable membrane are formed from the same material. The providing step may further include providing the dressing such that the end wall and the deformable membrane are molded integrally with one another. 
     Preferred dressings in accordance with the present invention and compression methods employing same reduce the time in which health care professionals must exert manual compression to a wound, while at the same time increasing patient mobility and comfort. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A more complete appreciation of the subject matter of the present invention and the various advantages thereof can be realized by reference to the following detailed description in which reference is made to the accompanying drawings in which: 
         FIG. 1  is an enlarged, schematic, cross-sectional view of one type of insertion site, showing a balloon catheter having passed over a guide wire through a guide cannula into the femoral artery of the patient; 
         FIG. 2  is a bottom plan view of one embodiment of the compression dressing of the present invention showing the side that faces the puncture wound; 
         FIG. 3  is a top plan view of the compression dressing of  FIG. 2 ; 
         FIG. 4  is a cross-sectional view of the compression dressing taken along line  4 - 4  of  FIG. 3  and showing the bladder in a deflated condition; 
         FIG. 5  is the same view as  FIG. 4 , but showing the bladder in an inflated condition; 
         FIG. 6  is a perspective view showing the application of the compression dressing to a patient, the bladder of the compression dressing being in a deflated condition; 
         FIG. 7  is a perspective view showing the application of the compression dressing to a patient, the bladder of the compression dressing being in an inflated condition; 
         FIG. 8  is an enlarged, schematic, cross-sectional view showing the insertion site of  FIG. 1  after the catheter, cannula and guide wire have been removed, and showing the use of the compression dressing to seal the puncture wound; and 
         FIG. 9  is a cross-sectional view of a compression dressing in accordance with an alternate embodiment of the present invention, showing the bladder in an inflated condition. 
     
    
    
     DETAILED DESCRIPTION 
     In certain procedures, for example, intra-aortic balloon pumping (“IABP”), percutaneous transluminal coronary angioplasty (“PTCA”) and angiography, as best seen in  FIG. 1 , a catheter or other device  10  is inserted through a puncture wound  14  and into a blood vessel or artery  16 , most frequently, the common femoral artery in the groin area of the patient&#39;s leg  20 . Puncture wound  14  includes a tissue channel extending through a layer of tissue separating artery  16  from the patient&#39;s skin Often, the insertion of device  10  is facilitated by passing the device over a guide wire  22  and through a guide cannula  24 . When the procedure (e.g., counterpulsation) has been completed, the device (e.g., the catheter), the guide wire and the guide cannula must be removed and the puncture wound closed. Although puncture wounds of the sort made by percutaneous procedures will generally, after removal of all cannulas and catheters, be in the nature of slits, for ease of understanding, they are depicted in the drawings herein more as holes. The shape of the puncture wound, however, is not critical. 
     It should be understood that the subject invention is independent of the nature of the medical device being used to treat the patient. Accordingly, the term “catheter” is used herein in a very generic and broad way to include not only “catheters” in the strict sense, but any device that is inserted into the body. 
     Similarly, the subject invention is independent of whether a particular blood vessel is involved, and if so, which blood vessel. While it is anticipated that the femoral artery will be the most commonly used blood vessel for many percutaneous procedures, other arteries as well as veins might just as easily be involved. 
     A compression dressing  100  for use in sealing puncture wound  14  is shown in  FIGS. 2 and 3 . Dressing  100  includes an expandable bladder  102  having an upper wall  104  and a lower membrane  106  enclosing an internal region  108 . Upper wall  104  is formed from a material that will resist substantial deformation at the pressures to which bladder  102  is inflated during normal use. Thus, for example, upper wall  104  may be formed from a rigid plastic material, a rigid metal or some other relatively rigid material. Preferably, upper wall  104  is formed from a transparent plastic disc so that the inflation of bladder  102  and any leakage of blood from puncture wound  14  can be readily observed therethrough. 
     In contrast, membrane  106  is formed from a pliant, air-impermeable material such that membrane  106  will deform upon inflation of bladder  102 . In one arrangement, membrane  106  may be formed from the same material as upper wall  104 . For example, in a one-piece molding operation, upper wall  104  may be formed with a relatively thick cross-section such that it will not substantially deform at the pressures to which bladder  102  is inflated during use, and membrane  106  may be formed with a relatively thin cross-section such that it will readily deform upon inflation of bladder  102 . Alternatively, upper wall  104  and membrane  106  may be formed from different materials altogether. 
     Bladder  102  in the inflated condition may have any shape capable of exerting sufficient pressure on the patient&#39;s leg to occlude bleeding. In a preferred arrangement, however, membrane  106  has a shape such that the inflated bladder  102  will taper from a larger size to a smaller size in the direction toward the patient. For example, in the inflated state, bladder  102  may have the shape of an inverted pyramid or cone. Such shapes will concentrate the pressure exerted by compression dressing  100  on a localized region of the patient, desirably a region overlying the wounded artery. Bladder  102  in the inflated condition may alternatively have a frusto-pyramidal or frusto-conical shape, thereby avoiding any pain to the patient which may result from having the inflated point of bladder  102  forced against the patient&#39;s skin Other shapes are also contemplated herein. Moreover, it will be appreciated that by varying the wall thickness and shape of membrane  106 , various levels of force and conformity with the contour of the patient&#39;s skin may be achieved. 
     Membrane  106  may be treated with an anti-bacterial coating in order to minimize the occurrence of infections in puncture wound  14  resulting from the use of compression dressing  100 . In addition, membrane  106  may be treated with any number of materials known to those skilled in the art to aid in the healing of puncture wound  14  or to reduce pain or complications. 
     Bladder  102  is secured to the lower surface of an attachment web  110 . Web  110  is preferably formed from a flexible material which will readily conform to the contour of the patient&#39;s leg. Particularly preferred are materials that are permeable to air, such as woven fabrics and perforated plastic sheets. The attachment of bladder  102  to web  110  may be made by an adhesive; mechanical means, such as sewing or stapling; ultrasonic or solvent welding; and any other known techniques. In a preferred arrangement, the edges of bladder  102  are encased within one or more layers of adhesive as discussed below in connection with  FIG. 9 . An aperture  112  may be formed in web  110  in a region overlying upper wall  104 . Aperture  112  may enable substantially the entirety of bladder  102  to be seen through web  110  to assure proper placement and operation of compression dressing  100 . 
     Web  110  may extend outwardly from bladder  102  in all directions so as to define a continuous region around bladder  102  by which dressing  100  may be attached to the patient&#39;s leg. However, web  110  need not extend outwardly from bladder  102  by equal amounts in all directions. Thus, as shown in  FIG. 2 , web  110  may include substantially perpendicular arms  114  and  116  which extend radially outwardly from bladder  102  by a greater extent than the remainder of web  110 . Although  FIG. 2  shows arms  114  as shorter than arms  116 , that is not necessarily the case; arms  114  may be longer than arms  116  or arms  114  and  116  may have substantially the same length. 
     The bottom surface of web  110  (i.e., the surface confronting the patient&#39;s skin) includes an adhesive layer  120  for adhering dressing  100  to the patient&#39;s skin in the region surrounding puncture wound  14 . Thus, dressing  100  is adhered to the patient and does not require that arms  114  or  116  circumscribe the body of the patient, in particular the leg or torso of the patient. Adhesive layer  120  may entirely coat the bottom surface of web  110 . Alternatively, adhesive layer  120  may be applied only in discrete regions of the bottom surface of web  110  such that the portion of web  110  adjacent bladder  102  is held tightly against the patient&#39;s skin Moreover, as noted above, adhesive layer  120  may be used to adhere upper wall  104  of bladder  102  to attachment web  110 , such as shown in  FIGS. 4 and 5 . A removable protective sheet  130  may cover adhesive layer  120  during shipping and handling. As explained below, protective sheet  130  is removed from dressing  100  prior to its use. 
     A mechanism  140  for inflating bladder  102  is provided on the upper wall  104  of the bladder. Mechanism  140  includes a tube  142  having one end connected to upper wall  104  by a connector  144  and communicating with the interior of bladder  102  through an aperture  146  in upper wall  104 . A one-way valve assembly  148  is connected to the other end of tube  142 . Any known inflation mechanism may be used to inflate bladder  102 . One such inflation device is a squeeze bulb, such as squeeze bulb  150  shown in  FIG. 6 , which may be connected to mechanism  140  through valve assembly  148 . Other inflation mechanisms include, but are not limited to, compressed air canisters, a centralized source of air distributed through the wall or ceiling, or a gas generated through a chemical reaction within bladder  102 , such as by crushing chemical-containing vials, etc. Alternatively, bladder  102  may be inflated by a fluid, such as saline, in order to provide weight to the dressing and reduce the compressibility of the inflated bladder. 
     The application of compression dressing  100  to a patient and the operation thereof will now be described with particular reference to  FIGS. 6-8 . After protective sheet  130  has been removed and before bladder  102  is inflated, the dressing  100  is applied so that adhesive layer  120  contacts the skin of the patient, and so that bladder  102  is positioned over or just upstream of puncture wound  14 . Squeeze bulb  150  or another inflation device may then be used to inflate bladder  102  to a desired pressure. Since upper wall  104  resists deformation as bladder  102  is inflated, as the inflation material fills internal region  108  of bladder  102 , membrane  106  will be pushed away from upper wall  104  and toward the patient&#39;s skin As this occurs, the adhesive layer  120  on web  110  holds bladder  102  in tight relationship against the skin of the patient. As a result, the inflation of bladder  102  causes the patient&#39;s skin and underlying tissue and artery to be compressed, thereby stanching the flow of blood through the tissue below. 
     Dressing  100  may be used with or without an initial period of manual compression. In that regard, manual compression may initially be applied to the wound site to achieve hemostasis before application of dressing  100 . After hemostasis has been achieved, dressing  100  may be applied and bladder  102  inflated. Alternatively, manual compression may be performed directly over dressing  100  after its application to the patient but before it has been inflated. In a further variant, manual compression may be performed directly over dressing  100  subsequent to inflation of bladder  102 . In this regard, membrane  106  may be formed with a shape which will facilitate the ease of applying this compression. In all of these methods, once manual compression has been completed, the inflated bladder  102  would continue to maintain pressure on the puncture wound to maintain hemostasis. 
     An alternate embodiment of a dressing in accordance with the present invention is illustrated as dressing  200  in  FIG. 9 . Dressing  200  is substantially the same as dressing  100  described above, but differs in the shape of the deformable membrane and in the method of securing the bladder to the attachment web. Thus, dressing  200  includes a deformable membrane  206  which is more rounded than membrane  106 , eliminating any sharp corners or edges which could cause discomfort for the patient. Also, dressing  200  includes a first layer of adhesive  220  which substantially coats one surface of attachment web  210  and adheres bladder  202  to the web, and a second layer of adhesive  280  which covers the peripheral edge of membrane  206  in the region in which the membrane is connected to upper wall  204 . With this arrangement, the outer edges of upper wall  204  and membrane  206  are encased within adhesive so that no free edges are exposed to the patient&#39;s skin. It will be appreciated that the same effect can be achieved without adhesive layer  280  having the same outward extent as adhesive layer  220 , or without adhesive layer  220  having the same outward extent as adhesive layer  280 . 
     Variants of dressings  100  and  200  will be readily apparent to those skilled in the art. For example, rather than having the attachment web adhesively secured to the patient&#39;s skin, arms  116  of the web may be formed with sufficient length that they can extend around the patient&#39;s leg and connect to one another, such as by tying, clasps, hook and loop fasteners, etc. Alternatively, the bladder may be secured to a patient&#39;s leg by a belt, strap or other device positioned over or operatively connected to the upper wall thereof. 
     Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as set forth in the appended claims.