Abstract:
A transvesicular drainage device, designed to drain excess fluid from a variety of locations in the human body into the bladder. The device may be used to treat ascites or any fluid collection within the body of a human, or a non human mammal.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application claims the priority of U.S. Provisional Application Serial No. 60/359,287, filed on Feb. 25, 2002 and U.S. Provisional Application Serial No. 60/389,346 filed on Jun. 18, 2002. The aforementioned provisional applications are incorporated by reference herein for all purposes. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The invention is a transvesicluar drainage device designed to drain excessive fluid from a bodily cavity into the bladder.  
         BACKGROUND OF THE INVENTION  
         [0003]    The present invention pertains to a chronic excess fluid drainage device. More specifically, the present invention pertains to a vesicular drainage device permitting unidirectional flow of excess fluid collections into the bladder.  
           [0004]    In medicine there are a variety of conditions which result in pathologic chronic collection of bodily fluids. Chronic pericardial effusions, normopressure hydrocephalus, hydrocephalus, chronic pulmonary effusion, and ascites are but a few of the conditions in which chronic fluid collections persist and result in increased morbidity and mortality.  
           [0005]    These conditions currently are treated by one of two methods: 1) external drainage with a high-risk of infection and long-term requirement for multiple punctures, 2) drainage to another body-cavity, or 3) various drugs. For pericardial effusions and hydrocephalus of all types, the treatment of choice is drainage to another region of the body. For pericardial effusions this entails a pericardial window, a highly invasive procedure in which a large section of the external heart cavity is removed. For hydrocephalus, the treatment typically involves the use of a ventriculo-peritoneal shunt draining the cerebrospinal fluid into the peritoneal cavity. This device frequently becomes clogged due to the proteinaceous environment of the peritoneal cavity and requires removal or revision.  
           [0006]    One conception of the present invention pertains to an ascites drainage device. More specifically, said conception pertains to a peritoneovesicular drainage device permitting unidirectional flow of peritoneal fluid from the peritoneal cavity into the bladder.  
           [0007]    Ascites is a highly debilitating complication associated with many medical conditions including liver failure and congestive heart failure. Untreated ascites can result in respiratory compromise, compression of the inferior vena cava (a vital blood vessel) and spontaneous bacterial peritonitis (a life-threatening condition). In order to treat chronic ascites, medicine has turned to both drugs and surgery.  
           [0008]    The drugs required to treat ascites are typically long-term and frequently result in complications. The most common pharmaceutical treatment of ascites involves the use of diuretics to remove fluid from patient&#39;s body through their urine. The difficulty with this treatment, though, is that fluid is removed from the entire body, including the circulating volume of blood, and can result in excessive loss of fluid required to perfuse the vital organs of the human body. Thus, even with religious application, though, the medicines frequently fail. In this case, surgical, or invasive, procedures are indicated.  
           [0009]    Currently the treatment of choice is called paracentesis. In paracentesis, the peritoneal fluid is drained through the abdominal wall via the insertion of a needle through the abdominal wall into the peritoneal cavity. This procedure, though, is only a temporary fix as the ascites quickly refills the peritoneal cavity in most chronic conditions. Furthermore, repeated paracenteses put the patient at increased risk for a life-threatening infection of their peritoneal cavity. Other surgical/invasive procedures involve treatment of the cause of the ascites (for example the Transjugular Intrahepatic Portosystemic Shunt) but these measures also frequently result in complications, which are often serious, and are thus performed hesitantly.  
           [0010]    The present invention avoids the difficulties associated with the current therapies for chronic ascites, namely, the procedure allows the drainage of peritoneal fluid without 1) the serious complications of pharmaceuticals, 2) the inconvenience, the substantial costs and the increased risk of infection associated with frequent paracenteses and 3) the multiple severe complications associated with more invasive and risky surgical operations to treat the cause of ascites.  
           [0011]    None of the existing devices are able to drain the peritoneal cavity except through temporary transabdominal insertion of a drainage catheter. These devices provide little improvement over the intermittent punctures of paracentesis and result in increased rates of infection if left in place for any length of time. The present invention will obviate the need for a long-term abdominal incision and, therefore, will eliminate the associated increased risk of serious infection.  
         SUMMARY OF THE INVENTION  
         [0012]    The present invention is a device designed for implantation in the wall of the bladder that permits the drainage of excessive fluid into the bladder.  
           [0013]    The device consists of a hollow, cylindrical column with flanges at both ends to provide secure anchorage in the bladder wall. Preferably there is a mechanism to provide unidirectional flow of fluid and prevent reflux of urine inside the column. A preferred embodiment of the device provides a passive ball-valve mechanism which allows for drainage of fluid into the bladder whenever a certain pressure is achieved at the collection site. A second preferred embodiment of the device provides an active valve mechanism which allows for controlled drainage of fluid into the bladder whenever the valve is actuated. The most preferred embodiment provides a pump in addition to an active valve mechanism.  
           [0014]    For ascites, the device can be implanted either through a transurethral or transabdominal route. In order to drain other sites, the bladder component is implanted as above, and a flexible tube or other conduit may be incorporated to place the receptacle end of the device in a fashion tailored to the region to be drained.  
           [0015]    In all embodiments, it is preferred that the device is constructed with biocompatible materials. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]    [0016]FIG. 1 shows a cross-sectional view of the device.  
         [0017]    [0017]FIG. 2 shows a cross-sectional view of the implanted device, designed to treat ascites, when the peritoneal pressure is sufficient to permit drainage.  
         [0018]    [0018]FIG. 3 shows a cross-sectional view of the implanted device, designed to treat ascites, when the peritoneal pressure is not sufficient to open the valve and no fluid flow occurs.  
         [0019]    [0019]FIG. 4 is an illustration of an example of an insertion device through which the current invention can be implanted in the bladder wall.  
         [0020]    [0020]FIG. 5 is an illustration of alternative embodiments of the invention with differing valve types, differing valve positioning and differing number of valves.  
         [0021]    [0021]FIG. 6 is an illustration of an alternative embodiment of the device in which an active, externally or internally controlled valve is utilized.  
         [0022]    [0022]FIG. 7 is an illustration of an alternative embodiment of the device in which a pump is included along the length of the tubing and placed subcutaneously for external control of drainage with a passive valve.  
         [0023]    [0023]FIG. 8 is an illustration of a few of the alternative embodiment of the device in which the peritoneal cavity, the pulmonary space and the ventricular space are able to be drained (pericardial drainage device not shown). 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0024]    As can be seen in FIG. 1, the present invention provides a novel vesicular drain  1  for implantation in the bladder wall  9  which will provide for unidirectional drainage of fluid into the bladder. The drain  1  provides two flanges at its ends  2 ,  3  which allow the device to be firmly anchored once placed across the bladder wall  9 . Alternative embodiments of the device may use other anchoring mechanisms, including, but not limited to: a screw thread on the outside of  1 , staples, sutures, an adhesive compound, and/or one or more barbs.  
         [0025]    The hollow shaft of the device contains a ball-valve  4  through which a positive closing pressure is provided by an attached spring  5 .  
         [0026]    The fluid collection interface of the device  1  may optionally include a large pore mesh  6  to allow for free flow of fluid while preventing incarceration of tissues at the drainage site.  
         [0027]    As can be seen in FIG. 2, once the pressure of the fluid collection (in this case the peritoneal cavity)  7  exceeds the combined force of the spring  5  and the pressure of the fluid-filled bladder cavity  8 , the peritoneal fluid  19  flows into the bladder cavity  8  through displacement of the ball-valve  4 . There, the peritoneal fluid mixes with the urine  20 .  
         [0028]    If the pressure of the bladder cavity  8  and the force of the spring  5 , though, are greater than the pressure of the fluid collection (in this case the peritoneal cavity)  7 , then the valve  4  will remain closed preventing reflux of urine  19  into the peritoneal cavity as depicted in FIG. 3.  
         [0029]    The device is designed to be placed transurethrally or transabdominally via an insertion device  10  such as that depicted in FIG. 4. The method of insertion allows for a single invasive procedure to provide a long-term solution to the otherwise difficult problem of refractory, chronic ascites.  
         [0030]    Alternatively, the device may contain a length of tubing  11  or other means of fluid transport to reach the fluid collection as well as an optional perforated receptacle  12 ,  17  and  18  through which the fluid collection will drain into the tubing. Such other means of fluid transport include, but are not limited to, conduit, catheter, channel, lumen, hose, pipe, duct, artery or vessel. The device may contain one or more valves of a variety of types including passive valves  4 ,  13  (flapper-valve),  14  (in FIG. 5), or active valves  15  (in FIG. 6) for tighter control of fluid drainage.  
         [0031]    The device is also designed to be able to incorporate a pump mechanism  16  in FIG. 7 which, when placed subcutaneously, can be actuated to provide an active pumping mechanism with the passive valves  4 ,  13 ,  14 , or with an active valve  15 . A third embodiment of the invention involves a unidirectional pump in place of the valve, controlling the flow of fluid through the device. A fourth conception of the invention involves a single unidirectional valve controlling the flow of fluid through the device.  
         [0032]    Alternatively, maneuvers which increase the pressure of the fluid cavity can also be utilized with the passive valves  4 ,  13 ,  14  to affect drainage such as bearing down to increase intraabdominal pressure to drain the peritoneal cavity or application of a girdle designed to increase abdominal pressure.  
         [0033]    The device will be designed to drain a variety of different fluid collections including, but not limited to, the peritoneal cavity FIG. 8A, pulmonary effusions FIG. 8B and excessive cerebrospinal fluid FIG. 8C. Pericardial effusion drain is not shown.  
         [0034]    Of particular interest to the inventors is the use of the invention to drain pulmonary effusions and other fluid collections in the lungs, in FIG. 8B.  
         [0035]    While these are the preferred embodiments, the device could employ any mechanism which provides a unidirectional passive or active valve for the drainage of any body fluid into the urinary bladder. This could involve filtration of the fluid through a polymer so as to sequester albumin and other proteins in the fluid collection while allowing flow of water and ions across the semi-permeable membrane. This could also involve an electronic valve triggered via communication across the tissues of the human body through EMFs such as radio, electricity, pressure, mechanical, magnetism, or other means of communication, allowing drainage only at selected times. The valve of the device can take many shapes and the device can be manufactured from any of a variety of materials with the only requirement being that of biocompatibility. Alternatively, the device, in either the active or passive embodiment, may incorporate anti-infective components in order to prevent the spread of infection between the body cavities. Such anti-infective components include, but are not limited to, bacteriostatic materials, bacteriocidal materials, one or more antibiotic dispensers, antibiotic eluting materials, entrained radioisotopes, a heating element, bioactive plastics, surfaces which encourage epithelialization, and coatings which prevent bacterial adhesion. Alternatively, the device, in either the active or passive embodiment, may incorporate anti-clogging components. Such anti-clogging components include, but are not limited to, an active ultrasonic component, an inner and outer sleeve which, when actively agitated, disrupt the inner lumen, surfaces which encourage epithelialization, enzyme eluting materials, enzyme eluting materials which specifically target the proteinaceous components of ascites, chemical eluting surfaces, an intermittent plunger mechanism, and coatings which prevent adhesion of proteinaceous compounds.  
         [0036]    While the device is primarily contemplated for use in human patients, the inventors also contemplate that the invention will have veterinary uses or product development purposes in equine, bovine, canine, feline, and other mammalian species.