Abstract:
A vessel holder supports a blood vessel during processing for use in bypass graft surgery. The holder comprises a base and a first fixture mounted on the base for holding a first end of the blood vessel. The first fixture has a fluid supply needle for inserting into the first end of the blood vessel. A second fixture is mounted on the base a predetermined distance from the first fixture for holding a second end of the blood vessel. The predetermined distance is adjustable for holding the blood vessel under tension. The device reduces labor and time for vessel preparation. With various optional features, the device obtains safer application of pressurized saline solution when testing for leaks, better visualization for inspecting the vessel for surgical use, reliable protection of the vessel from accidental damage, and convenient immersion of the vessel in a bath for preservation until needed in the surgery.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    Not Applicable. 
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH 
       [0002]    Not Applicable. 
       BACKGROUND OF THE INVENTION 
       [0003]    The present invention relates in general to a holder for a blood vessel harvested from a patient for use in cardiac bypass graft surgery, and, more specifically, to a device for assisting in sealing branch stubs and pressure testing of the blood vessel. 
         [0004]    In coronary artery bypass grafting (CABG), a blood vessel or vessel section, such as an artery or vein, is “harvested” (i.e., removed) from its natural location in a patient&#39;s body for use elsewhere in the body. In CABG surgery, the blood vessel is used to form a bypass between an arterial blood source and the coronary artery that is to be bypassed. Among the preferred sources for the vessel to be used as the bypass graft are the saphenous veins in the legs and the radial artery in the arms. 
         [0005]    Endoscopic surgical procedures for harvesting a section of a vein (e.g., the saphenous vein) subcutaneously have been developed in order to avoid disadvantages and potential complications of harvesting through a continuous incision (e.g., along the leg) for the full length of the desired vein section in order to provide adequate exposure for visualizing the vein and for introducing surgical instruments to sever, cauterize and ligate the tissue and side branches of the vein. One such minimally-invasive technique employs a small incision for locating the desired vein and for introducing one or more endoscopic harvesting devices. Primary dissection occurs by introduction of a dissecting instrument through the incision to create a working space and separate the vein from the surrounding tissue. Then a cutting instrument is introduced into the working space to sever the blood vessel from the connective tissue surrounding the section to be harvested and any side branches of the blood vessel. The branches may be clipped and/or cauterized. 
         [0006]    In one typical procedure, the endoscopic entry site is located near the midpoint of the vessel being harvested, with dissection and cutting of branches proceeding in both directions along the vessel from the entry site. In order to remove the desired section of the blood vessel, a second small incision, or stab wound, is made at one end thereof and the blood vessel section is ligated. A third small incision is made at the other end of the blood vessel section which is then ligated, thereby allowing the desired section to be completely removed through the first incision. Alternatively, only the first two incisions may be necessary if the length of the endoscopic device is sufficient to obtain the desired length of the blood vessel while working in only one direction along the vessel from the entry point. 
         [0007]    An example of a commercially available product for performing the endoscopic vein harvesting described above is the VirtuoSaph™ Endoscopic Vein Harvesting System from Terumo Cardiovascular Systems Corporation of Ann Arbor, Mich. Endoscopic vein harvesting systems are also shown in U.S. Pat. No. 6,660,016 to Lindsay and U.S. patent application publication 2005/0159764A1 in the name of Kasahara et al, both of which are incorporated herein by reference in their entirety. 
         [0008]    After a vein is removed from the patient&#39;s body, it must be prepared for use as a bypass graft. Preparation includes ligating (i.e., closing off) each branch stub, injecting a solution into the vein under pressure to test for leaks, and otherwise inspecting the condition of the blood vessel. In the conventional procedures, branch stubs may be ligated using sutures for tying off each stub or staples may be employed for clamping off each stub. This processing of the blood vessel is normally performed by placing the blood vessel on a sterile surface over a patient&#39;s leg nearby the point from where it was harvested. Typically, two people (e.g., medical technicians, nurses) work together to hold the vein, apply a syringe of saline solution to pressurize the vessel, tie off or clip branch stubs as the vein is distended by the saline solution, and check for leaks. The prior art procedure is labor intensive and is difficult to perform on a loose, unsupported vein lying over an uneven surface. Since the amount of pressurized saline solution injected into a blood vessel is manually controlled according to the pressure being applied against a plunger of a syringe, the medical technician occasionally damages a blood vessel by over-pressurizing it. Other inadvertent damage may also occur during handling since the blood vessel is unrestrained and unprotected from other objects until such time as it is transferred to a bath of saline solution after it has been inspected by a surgeon performing the graft. 
       SUMMARY OF THE INVENTION 
       [0009]    Among the benefits that can be realized according to different aspects of the invention are reduced labor and time for vessel preparation, safer application of pressurized saline solution when testing for leaks, better visualization for inspecting and measuring the vessel for surgical use, reliable protection of the vessel from accidental damage, and convenient immersion of the vessel in a bath for preservation until needed in the surgery. 
         [0010]    In one aspect of the invention, a vessel holder supports a blood vessel during processing for use in bypass graft surgery. The holder comprises a base and a first fixture mounted on the base for holding a first end of the blood vessel. The first fixture has a fluid supply needle for inserting into the first end of the blood vessel. A second fixture is mounted on the base a predetermined distance from the first fixture for holding a second end of the blood vessel. The predetermined distance is adjustable for holding the blood vessel under tension. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  shows a saphenous vein being removed from the leg of a patient following an endoscopic procedure. 
           [0012]      FIG. 2  is a perspective view of one embodiment of a vessel holder according to the present invention. 
           [0013]      FIG. 3  is a perspective view of another embodiment of the vessel holder having an intermediate branch clamp. 
           [0014]      FIG. 4  is a perspective view of a further embodiment of the invention having a removable cover that is used to provide a bath. 
           [0015]      FIG. 5  is a cross-sectional perspective view according to another embodiment of the present invention. 
           [0016]      FIG. 6  is a perspective view of another embodiment of the vessel holder. 
           [0017]      FIG. 7  shows a modification to the embodiment of  FIG. 6  including a vessel bath with an adjustable length. 
           [0018]      FIG. 8  is a perspective view of a further embodiment of the invention having a sleeve for fitting over a limb of the patient. 
           [0019]      FIG. 9  is a perspective view of yet another embodiment of the vessel holder having graduation marks and labels for assisting in determining the length of a vessel being prepared. 
           [0020]      FIG. 10  is a partial view of the vessel holder in  FIG. 9  wherein a reservoir holds a prepared blood vessel in a bath of saline solution until needed for the surgery. 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0021]    The present invention provides a device for supporting a blood vessel during processing for use in bypass graft surgery. The vessel holder device comprises a base and first and second fixtures mounted on the base. The first fixture holds a first end of the blood vessel and has a fluid supply needle for inserting into the first end of the blood vessel. The second fixture holds a second end of the blood vessel at a predetermined distance from the first fixture. The predetermined distance between the first and second fixtures is adjustable so that the blood vessel is held under a desired amount of tension. By suspending the blood vessel with a gentle tension between the first and second fixtures, processing of a blood vessel can be performed by a single individual in a shorter period of time and with less damage to the blood vessel. 
         [0022]    Referring now to  FIG. 1 , a saphenous vein  10  is being removed from a patient&#39;s leg  11  through an incision  12 . During harvesting, main vessel  10  is severed from side branches extending from vessel  10  and then opposite ends of vessel  10  are cut at stab wounds  13  and  14  to free it for removal. The present invention may also be employed with blood vessels harvested using different surgical methods or from different areas of the patient&#39;s body. 
         [0023]    The present invention may include a vessel holder device supplied as a disposable, sterile device for use by a physician&#39;s assistant or nurse to prepare a blood vessel. In a preferred embodiment, the device is constructed as a disposable stand molded from polycarbonate or other biocompatible material and using stainless steel attachment devices arranged to apply the necessary tension to the blood vessel to keep it taut in order to make tying or clipping of branch stubs easier than in the prior art wherein a loose blood vessel lies on an uneven leg surface. According to a first embodiment, the device in  FIG. 2  includes a base  20  supporting a first fixture  21  and a second fixture  22  wherein base  20  includes interlocking pieces  23  and  24  to adjust the distance between fixtures  21  and  22 . A locking mechanism of any known type such as a locking tab  25  is provided to maintain the desired predetermined distance according to the tension to be applied. 
         [0024]    First fixture  21  includes a fluid supply needle  26  extending from a mounting boss  27  rotationally mounted to fixture  21 . A rotation wheel  28  fixed to boss  27  allows for manual rotation of fluid needle  26  and boss  27 . One end of blood vessel  10  is inserted over fluid supply needle  26  and is secured thereto by tying a suture  29  over the end of blood vessel  10  and tightening. 
         [0025]    Second fixture  22  has a clamp  30  rotationally mounted thereon together with a rotation wheel  31 . Clamp  30  has a pair of jaws  32  and  33  for grasping the end of blood vessel  10 . With the first end of blood vessel  10  secured to needle  26 , the distance between fixtures is adjusted (if need be) to a distance at which there is sufficient slack in vessel  10  to secure it to clamp  30 . After attaching both ends of blood vessel  10 , the length of base  20  is adjusted outward in order to provide a predetermined distance between fixtures  21  and  22  so that blood vessel  10  is held under a desired, gentle tension. With blood vessel  10  suspended between fixtures  21  and  22 , each branch stub can be conveniently tied off or clipped by a single user. Blood vessel  10  can easily be reoriented by rotating it so that a desired branch stub is facing the user by moving rotation wheels  28  and  31  together. An additional manual clamp  34  may be attached to a branch stub during ligation to pull it perpendicularly away from the main vessel in order to make suturing easier. 
         [0026]    Boss  27  and fluid supply needle  26  include a hollow passage coupled to a feed line  35  running from a syringe  36  mounted to base  20 . Thus, saline solution from syringe  36  can be coupled through feed line  35 , boss  27 , and needle  26  to the interior of blood vessel  10 . Saline solution or other fluid may be introduced into blood vessel  10  to gradually distend it along its length to each branch stub  36  for easier ligating of the branch stubs. In addition, fluid from feed line  35  is introduced into blood vessel  10  after completing all ligations in order to test them for leaks. In order to ensure that excessive pressures that may otherwise damage blood vessel  10  are not inadvertently introduced, a pressure gauge  37  is connected to feed line  35  allowing the user to monitor pressure being applied to the vessel and to maintain it at a safe level below a known threshold. 
         [0027]      FIG. 3  shows an alternative embodiment having an additional feature of providing a branch clamp  40  that is movable along a support rod  41 . Clamp  40  includes jaws  42  and  43  for grasping a branch stub  36  so that branch stub  36  is positively maintained in place to facilitate the tying of a suture around the stub. To process a next branch stub, the user removes branch clip  40  from one branch stub, rotates the rotation wheels to orient a next branch stub in the direction towards support rod  41 , and clamp  40  is slid along support rod  41  so that it can easily grasp the next branch stub. 
         [0028]      FIG. 4  shows an optional enhancement to the present invention for maintaining blood vessel  10  in a saline solution bath after the ligation and pressure testing steps. Thus, the vessel holder device may be flipped over and placed into a cover  45  having a reservoir  46  containing a sufficient depth of saline solution to immerse blood vessel  10  when the vessel holder is flipped over and inserted into reservoir  46 . A flat block  47  may be provided at the bottom of cover  45  to maintain reservoir  46  in the upright position. Cover  45  may preferably be comprised of an injection molded polycarbonate or other biocompatible materials. Cover  45  and base  20  may fit together in a manner that preserves sterility during shipment from the point of manufacture to the point of use. 
         [0029]      FIG. 5  shows an alternative embodiment wherein a reservoir is incorporated into a base  50 . Thus, base  50  includes a recess  51  for receiving a rotatable member  52  carrying a first fixture  53  for receiving blood vessel  10  and a swivel clamp  54  at the opposite end of member  52  for supporting the other end of blood vessel  10 . A fluid supply needle  55  in first fixture  15  receives fluid from a syringe  56  and feed line  57  as described in the previous embodiment, or from an optional syringe  58  connected coaxially with needle  55 . A branch clamp  60  is able to clamp branch stubs at its proximal end and is slideably mounted in a longitudinal groove  61  of member  52  at its proximal end. Clamp  60  can be slid back and forth in the direction shown by arrow  62  to coincide with branch stubs to be ligated. 
         [0030]    After processing of blood vessel  10 , rotatable member  52  may be rotated around its axis  63  so that after 180 degrees of rotation, blood vessel  10  resides in a bath chamber  64  running longitudinally at the bottom of recess  51  in base  50 . Recess  51  may include a cut out area  65  to accommodate the space needed by branch clip  60  when member  52  is rotated to place blood vessel  10  into bath  64 . 
         [0031]      FIG. 6  shows an embodiment similar to  FIG. 5  for providing an integral bath chamber  64 . Base  50  includes an end cover  65  having an arcuate slot  66  in the near end and a mirror image slot in the opposite end (not shown). When rotated, fixture components  67  (e.g., an extension of the mounting boss for connecting with a feed line at one end and a protrusion of a clamp shaft at the other end), traverse arcuate slots  66  allowing rotatable member  68  to flip over so that the blood vessel resides within bath chamber  64 . A locking mechanism such as detents (not shown) in a hinge mechanism  69  provide for locking member  68  into a vessel processing position or a vessel immersing position. 
         [0032]    In the embodiment shown in  FIG. 6 , rotatable member  68  and base  50  have a fixed length. An adjustable distance between fixtures can be obtained by making the fluid supply needle and/or the clamp repositionable within their fixture. Member  68  and base  50  could also be constructed using telescopic parts in order to provide the adjustable distance. For example,  FIG. 7  shows a telescopic base  70  with a first member  71  having a channel section  72 . A second member  73  has a channel section  74  that is sealingly retained in channel section  72 . Base  70  and a similarly telescoping rotatable member attached to members  71  and  73  would be extended or contracted together according to the length of a blood vessel being processed and the length of the immersion bath automatically accommodates the telescoped size of the rotatable member. Channel sections  72  and  74  would be filled with the appropriate volume of saline or other solution at the point of use. 
         [0033]      FIG. 8  shows a C-shaped sleeve  75  mounted underneath a base  76  according to any embodiment of a vessel holder device of the present invention. Sleeve  75  is placed over a limb of the patient (e.g., the opposite leg from the one used to harvest a saphenous vein) for convenient processing of the blood vessel near the place from which it is harvested and near the place where it will be reinserted into the patient. 
         [0034]      FIGS. 9 and 10  show yet another embodiment of a vessel holder. A base  80  supports a cylindrical tube member  81  having end flanges  82  and  83  and an intermediate flange  84 . A clamp  85  is mounted to flange  83  for retaining one end of blood vessel  10 . A syringe  86  extends through an aperture  97  in flange  82  and has a needle  87  extending through an aperture  98  in flange  84  to retain the other end of blood vessel  10 . A snug but movable fit of syringe  86  in the apertures can provide an adjustable distance to achieve the desired tension in blood vessel  10 . A branch clamp arm  90  is slidably mounted on a support rod  91  that extends between flanges  83  and  84 . 
         [0035]    Along the central tubular body of member  81 , a plurality of graduations  92  are scribed or otherwise created at predetermined intervals. A plurality of labels  93  are also applied to member  81  to assist in determining the length of a vessel mounted to the vessel holder. 
         [0036]    Tube member  81  includes a cavity  94  for providing a bath for storing blood vessel  10  after processing. As shown in  FIG. 10 , the vessel holder may be placed on end so that cavity  94  may be filled with a saline solution to a sufficient depth to immerse blood vessel  10 . Cavity  94  preferably only penetrates into tube member  81  for a short distance (e.g., to the vicinity of flange  84 ) rather that extending the full length of member  81 . A stopper  96  is provided for enclosing cavity  94  to further protect blood vessel  10  and/or to allow pre-filling with saline solution.