Abstract:
Paracentesis apparatus providing increased fluid transfer capacity, comprising a single centesis needle and at least two vacuum sources. The centesis needle is connected to the vacuum sources by a conduit which is split to form a flow path to each vacuum source. The conduit may comprise flexible tubing, and may include an in-line valve and a connector for engaging the vacuum sources. The vacuum sources may comprise evacuated bottles. Albumin may be administered to patients undergoing paracentesis.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to medical procedures, and more particularly, to method and apparatus for increasing throughput of flow in the course of a paracentesis. 
       BACKGROUND OF THE INVENTION 
       [0002]    From time to time, it becomes necessary to remove ascites or fluid from the abdominal area of a patient. In most cases, this is to reduce internal pressure, although other reasons may exist. In conventional practice, a needle is inserted through the abdominal wall into the patient and is connected by tubing to a vacuum source such as an evacuated bottle having sufficiently strong partial vacuum as to draw fluid from the abdomen. Where large volumes of fluid must be removed, care must be taken to moderate the rate of removal so as not to cause sudden drops in blood pressure. 
         [0003]    In the conventional form of paracentesis the needle is connected by a tube to a single vacuum source or bottle. 
         [0004]    Despite the necessity of considering blood pressure, it would be desirable to greatly reduce the time necessary to accomplish paracentesis. For example, using conventional practice, it may require two hours or more to remove ten liters of fluid. Obviously, the rate of fluid extraction could be greatly expedited without threat to stability of blood pressure. It would be undesirable to utilize a second needle and associated apparatus, as this introduces a second and undesirable penetration of body tissues, complication to the medical procedure, and increased costs. 
       SUMMARY OF THE INVENTION 
       [0005]    The present invention addresses the above stated goal by providing a way to expedite removal of fluid from the abdomen while utilizing only one penetration of the abdominal wall or other bodily tissue. To this end, apparatus to perform a paracentesis operation may utilize a centesis needle connected to a tube, a manifolding fitting which divides flow from the tube into several separate streams, and one additional tube for each of the separate streams. Each of these additional tubes may be connected to an evacuated bottle or other vacuum source. 
         [0006]    The novel apparatus and associated method may utilize conventional centesis needle, tubing, fittings, and vacuum sources, and therefore need not require special or dedicated apparatuses. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    Various objects, features, and attendant advantages of the present invention will become more fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein: 
           [0008]      FIG. 1  is a plan view of paracentesis apparatus according to at least one aspect of the invention. 
           [0009]      FIG. 2  is a block diagram of steps of a method of using the paracentesis apparatus of  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION 
       [0010]    Referring first to  FIG. 1 , according to at least one aspect of the invention, there is shown paracentesis apparatus  100  including a centesis needle  102  which has been installed in a mammalian body  2  containing ascites  4  such as through the abdominal wall (not explicitly shown) for purposes of extraction of the ascites  4  from the mammalian body  2 . Portions of the centesis needle  2  project to the exterior of the mammalian body  2 . 
         [0011]    The paracentesis apparatus  100  may comprise a first conduit  104  having a proximal end  106  disposed in fluid communication with the centesis needle  102 , and a distal end  108 . The first conduit  104  divides or splits into two flow paths. The point of split or bifurcation may occur for example at a manifolding fitting  110  which comprises a first port  112  which is compatible with the first conduit  104 , and at least two additional ports  114 ,  116 . The manifolding fitting  110  may be described as a three-way fitting comprising the first port  112  and the two additional ports  114 ,  116 . 
         [0012]    Each of the two flow paths is contained within one of two additional conduits  118  or  120 . A number of vacuum sources such as evacuated bottles  122 ,  124  is connected to the additional conduits  118 ,  120 . The terms vacuum source and evacuated bottle will generally be used interchangeably hereinafter, as feasibility and context dictate. The number of vacuum sources is equal to the number of the additional ports  114 ,  116  and to the number of additional conduits  118 ,  120 . Just as the first conduit  114  is disposed in fluid communication with the centesis needle  102  and the first port  112 , the additional conduits  118 ,  120  are disposed in fluid communication with respective additional ports  114 ,  116 , and with the vacuum sources. In summary, flow from the centesis needle  102  splits into alternative flow paths represented by the additional conduits  118 ,  120 , and ultimately to the vacuum sources. 
         [0013]    The first conduit  104  and the additional conduits  118 ,  120  may be provided for example by flexible tubing. It should also be noted that description of the paracentesis apparatus  100  in terms of single conduits such as the first conduit  104  and the additional conduits  118  and  120  need not imply that these conduits each consist of only one continuous section of tubing. It would be possible to provide plural sections of tubing or other conduits joined by suitable connectors (this option not shown), provided that the divided flow scheme described above be present. Also, it would be possible to increase the number of vacuum sources beyond the two explicitly shown. 
         [0014]    Flow to each of the evacuated bottles  122  or  124  may be controlled by a valve arrangement comprising valves  126 ,  128  each disposed serially in one of the additional conduits  118 ,  124  respectively. Each valve  126 ,  128  enables discontinuing communication of its associated evacuated bottle  122  or  124 , thereby selectively discharging ascites into only one of the evacuated bottles  122  and  124 , or in some implementations of the invention, modifying flow rate in each of the additional conduits  118 ,  120 . 
         [0015]    Of course, it would be possible to provide only one of the additional conduits  118  or  124  with a valve  126 ,  128  if desired. However, greatest versatility of the system is enabled when a valve  126  or  128  is disposed serially in each one of the additional conduits  118 ,  120 . 
         [0016]    Each one of the additional conduits  118 ,  120  preferably further comprises a respective connector  130 ,  132  which is configured to engage the vacuum source and to maintain its respective additional conduit in fluid communication with the vacuum source. Each of the connectors  130 ,  132  may comprise spiked tubing. 
         [0017]    In use, the apparatus  100  may be utilized to perform a method  200  of conducting extraction of ascites from a mammalian body, as shown in  FIG. 1 . As summarized in  FIG. 2 , the method  200  may comprise the following steps. In a step  202 , one and only one centesis needle such as the centesis needle  102  is installed in the mammalian body so as to be in fluid communication with the ascites, and to project to the exterior of the mammalian body. In a step  204 , ascites is drawn from the centesis needle through a conduit such as the first conduit  104 . The step  204  may comprise a further step  206  of drawing ascites from the centesis needle through flexible tubing. The method  200  may include a step  208  of splitting the conduit, such as the first conduit  104 , into at least two flow paths. The method  200  may include a step  210  of connecting each one of the flow paths to a dedicated vacuum source. As employed herein, the term dedicated signifies that the dedicated element is associated with a respective one of the additional conduits  118  or  120 . The step  210  may comprise a further step  212  of connecting each one of the flow paths to one evacuated bottle such as the evacuated bottles  122 ,  124 . 
         [0018]    The step  210  may comprise a further step  214  of connecting each one of the flow paths to one evacuated bottle using a flexible conduit for at least one and preferably both of the two flow paths. 
         [0019]    The method  200  may comprise a step  216  of selectively discharging ascites into one of the vacuum sources. This may be done using the valves  126 ,  128 . 
         [0020]    In a step  218 , the method  200  may comprise administering albumin to patients undergoing paracentesis. The step  218  may comprise a further step  220  of administering albumin to the patient intravenously. The step  218  may comprise a further step  222  of administering albumin at a rate of four grams to ten grams of albumin for each liter of ascites removed. In a most preferred implementation, the step  222  may comprise a further step  224  of administering albumin at the rate of about seven grams of albumin for each liter of ascites removed. It is preferred to use about a twenty-five percent solution of albumin when administering albumin at the rate of seven grams of albumin per liter of ascites removed. 
         [0021]    It is not necessary to penetrate the abdominal wall to gain access to fluid being drained, although such practice is conventional. Depending upon the particular medical procedure, the same apparatus and method could be utilized while penetrating other body tissues, such as a lateral or dorsal surface, or by utilizing a natural body opening such as a rectal opening, vaginal opening, urethral opening, or exploiting a pre-existing wound or incision. 
         [0022]    While the present invention has been described in connection with what is considered the most practical and preferred embodiment, it is to be understood that the present invention is not to be limited to the disclosed arrangements, but is intended to cover various arrangements which are included within the spirit and scope of the broadest possible interpretation of the appended claims so as to encompass all modifications and equivalent arrangements which are possible.