Abstract:
A cannula connects an organ with a perfusion system that monitors, treats, sustains and/or restores the viability of the organ and/or that transports and/or stores the organ. At least part of a cannula may be made of a soft elastomer to help avoid damage to the organ. In embodiments, the cannula includes a top portion, a bottom portion, a sealing ring and two compression straps. In embodiments, the cannula includes a top portion and a flexible bottom portion that may be attached to the top portion. In embodiments, part of the cannula is inserted directly into an artery and a suture is used to tie the artery in place. Also, the cannula may include an attachment feature that can be used to connect the cannula to an organ platform or chair. Various features of the cannula may allow a visual check for and venting of air bubbles in the cannula.

Description:
BACKGROUND OF THE INVENTION 
     This nonprovisional application claims the benefit of U.S. Provisional Application No. 60/460,875, filed Apr. 8, 2003 and Provisional Application No. 60/405,321, filed Aug. 23, 2002. 
    
    
     The invention relates to cannulas and clamping methods. More specifically, the invention relates to cannulas, cannula mount assemblies and clamping methods for perfusing one or more organs to monitor, treat, sustain and/or restore the viability of the organ(s) and/or for transporting and/or storing the organ(s). 
     Various devices have been developed that couple the anatomy of an organ being perfused to a machine or other equipment. Such devices are typically referred to as perfusion clamps or simply cannulas. Although the term cannula in general use has other meanings, the term cannula is used generically throughout the specification to refer to a clamp or other device that provides a connection through which a fluid flow may be established. 
     Currently, perfusionists select between two types of cannulas, depending on whether an aortic patch is available. A first type of cannula, as described in U.S. Pat. No. 5,728,115 to Westcott et al., which is hereby incorporated by reference, is shown in  FIGS. 1-3 . A clamping device (cannula)  10  is used to couple the perfusion cannula to the renal aorta  34 . The clamp  10  includes two longitudinal members  12  and  14  which pivot about a pin  16 . The proximal end of the member  12  includes an integral handle  18 , while the proximal end of the member  14  includes an integral handle  20 . The distal end of the member  12  includes an integral clamp head  24 , while the distal end of the member  14  includes an integral clamp head  26 . Clamp head  26  includes a nipple  28  attached thereto. Movement of the handles  18  and  20  toward one another forces the members  12  and  14  to pivot about the pin  16 , thereby forcing the clamp heads  24  and  26  of the members  12  and  14  away from one another. A spring  22  is positioned between the handles  18  and  20  in order to bias the handles apart. This, in turn, tends to force the clamp heads  24  and  26  together. Therefore, the clamp heads  24  and  26  of the distal ends of the members  12  and  14  are engaged in clamping relationship unless an external compressive force is applied to the handles  18  and  20 . 
     The distal end of the member  12  comprises an elongated, hollow, annular clamp head  24 . A lumen  32  extends through the nipple  28 . 
     In use, the clamp  10  is attached to the renal aorta  34  of a donor organ such as a kidney  36  by opening the clamp  10 , passing the distal end  38  of the renal aorta  34  through the annular clamp head  24 , holding the distal end  38  of the renal aorta  34  over the annular clamp head  24 , and releasing pressure on the handles of the clamp  10  in order to allow the clamp head  26  to engage the distal end  38  of the renal aorta  34  against the annular clamp head  24 . A catheter  40  may then be attached to the nipple  28  in order to provide perfusion of liquid through the lumen  32  and into the renal aorta  34 . 
     A second type of cannula  50 , used when no aortic patch is available, is shown in  FIG. 4 . No aortic patch may be available due to anatomical constraints or a living donor recovery. An infuse line (not shown) is connected to a top tube portion  52  of the cannula  50 . A lower tube portion  54  of the cannula is inserted into the renal artery. The lower tube portion  54  may be sutured into place. 
     SUMMARY OF THE INVENTION 
     The present invention focuses on avoiding damage to an organ during perfusion while connecting the organ to a machine or system for monitoring, treating, sustaining and/or restoring the viability of the organ and preserving the organ for storage and/or transport. The invention is directed to apparatus and methods for connecting an organ to be perfused with a perfusion machine or system that monitors, treats, sustains and/or restores the viability of the organ and/or that transports and/or stores the organ. In particular, apparatus and methods according to the invention are suitable for use with the perfusion systems and methods described in U.S. Pat. No. 6,209,343, which is hereby incorporated by reference in its entirety. Thus, apparatus and methods according to the invention are suitable for use with organ perfusion at normothermic temperatures and organ perfusion at hypothermic temperatures. Apparatus and methods according to the invention are suitable for use with an organ cassette, such as that disclosed in the &#39;525 application, and/or with a mother unit, and/or with a portable transport apparatus, such as, for example, a cooler or a portable container such as that disclosed in co-pending U.S. application Ser. No. 09/161,919, filed Sep. 29, 1998, which is hereby incorporated by reference in its entirety. The apparatus and methods according to the invention are also suitable for use with the organ cassette systems and methods described in copending U.S. Provisional Applications Nos. 60/459,986 and 60/459,981, filed Apr. 4, 2003, which are hereby incorporated by reference in their entirety. 
     Various exemplary embodiments of apparatus and methods according to the invention are atraumatic to the aortic patch or general tissue that is to be connected. In various exemplary embodiments, soft medical grade elastomers are utilized to contact the delicate inner wall of the patch or tissue. In various exemplary embodiments, the sealing force is spread out over a large surface area, helping to reduce the force on a specific section of the patch or tissue. 
     Various exemplary embodiments of apparatus and methods according to the invention seal against aortic patches or other tissue with a hard plaque build-up. In various exemplary embodiments, an elastomeric sealing ring is used that follows the contour of plaque build-up. In various exemplary embodiments, a relatively large sealing surface provides good contact. 
     Various exemplary embodiments of apparatus and methods according to the invention provide visual access to an air bubble trap. In various exemplary embodiments, at least a portion of the cannula is made of a translucent material to provide viewing into an upper portion of the cannula that traps air bubbles. 
     Various exemplary embodiments of apparatus and methods according to the invention provide a means to prime and/or vent air bubbles from the cannula, connecting tubes and/or the organ without disconnecting the cannula from the tissue. In various exemplary embodiments, a fitting allows the user to open a port to let air out. 
     Various exemplary embodiments of apparatus and methods according to the invention provide a means to handle organs with multiple arteries. In various exemplary embodiments, a relatively large sealing ring accommodates patches or tissues containing multiple arteries. In various exemplary embodiments, a fluid exit may be shaped to accommodate patches or tissues containing multiple arteries. In various exemplary embodiments, a fitting allows the user to network multiple cannulas that are each connected to patches or placed straight into an artery. 
     Various exemplary embodiments of apparatus and methods according to the invention allow an aortic patch or tissue to be positioned and fixed to the cannula prior to clamping. In various exemplary embodiments, the aortic patch or tissue may be located and fixed onto flanges prior to clamping, for example, with standard surgical clamps. 
     Various exemplary embodiments of apparatus and methods according to the invention allow an artery to be held at a fixed tension. In various exemplary embodiments, the cannula includes locating or positioning features that may be securely positioned, for example, onto an organ platform or chair, such as the chair described in the incorporated &#39;525 application, to keep the artery from getting twisted and/or stressed. 
     Various exemplary embodiments of apparatus and methods according to the invention provide parallel sealing surfaces. In various exemplary embodiments, the sealing surfaces are not constrained by a hinge, allowing the surfaces to remain parallel during clamping. 
     Various exemplary embodiments of apparatus and methods according to the invention provide a secure connection to an infuse line. In various exemplary embodiments, a locking fitting ensures a secure, leak-proof connection to tubing of a perfusion machine or system. 
     Various exemplary embodiments of apparatus and methods according to the invention provide a cannula that is suitable for multiple size organs, i.e., one-size-fits-all. In various exemplary embodiments, a bottom portion of the cannula may be shaped, for example with standard scissors or knives, to accommodate various patch sizes and multiple arteries. 
     Various exemplary embodiments of apparatus and methods according to the invention allow the aortic patch or tissue to be in a natural position. In various exemplary embodiments, an inner clamp surface can be shaped cylindrically to allow the aortic patch or tissue to be fixed in its natural shape. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other aspects and advantages of the invention will become apparent from the following detailed description of exemplary embodiments when taken in conjunction with the accompanying drawings, in which: 
         FIGS. 1-3  show a first type of a known perfusion clamp or cannula; 
         FIG. 4  shows a second type of a known perfusion clamp or cannula; 
         FIG. 5  is a perspective view of a first exemplary embodiment of a cannula and a cannula mount according to the invention; 
         FIG. 6  is an exploded view of the first embodiment shown in  FIG. 5 ; 
         FIG. 7  is a perspective view of a top portion of the first embodiment shown in  FIG. 5 ; 
         FIG. 8  is a perspective view of a bottom portion of the first embodiment shown in  FIG. 5 , shown with the cannula mount; 
         FIG. 9  is a perspective view of a sealing ring of the first embodiment shown in  FIG. 5 ; 
         FIG. 10  is a perspective view of a compression strap of the first embodiment shown in  FIG. 5 ; 
         FIG. 11  is a perspective view of a second exemplary embodiment of a cannula and a cannula mount according to the invention; 
         FIG. 12  is a perspective view of a top portion of the second embodiment shown in  FIG. 11 ; 
         FIG. 13  is a perspective view of a bottom portion of the second embodiment shown in  FIG. 11 ; 
         FIGS. 14  is a perspective view of the cannula mount of the second embodiment shown in  FIG. 11 ; 
         FIG. 15  is a perspective view of a third exemplary embodiment of a cannula and a cannula mount according to the invention; 
         FIG. 16  is a perspective view of a cannula body of the third embodiment shown in  FIG. 15 ; 
         FIG. 17  is a perspective view of the cannula mount of the third embodiment shown in  FIG. 15 ; 
         FIG. 18  is a perspective view of a fourth exemplary embodiment of a cannula, a cannula mount and a platform according to the invention; 
         FIG. 19  is an exploded view of the fourth embodiment shown in  FIG. 18 ; 
         FIG. 20  is a perspective view of a top portion of the fourth embodiment shown in  FIG. 18 ; 
         FIG. 21  is a perspective view of a bottom portion of the fourth embodiment shown in  FIG. 18 ; 
         FIG. 22  is a perspective view of a sealing ring/compression straps of the fourth embodiment shown in  FIG. 18 ; 
         FIG. 23  of the cannula mount of the fourth embodiment shown in  FIG. 18 . 
     
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     Preservation of organs by machine perfusion has been accomplished at hypothermic temperatures with or without computer control with crystalloid perfusates and without oxygenation. See, for example, U.S. Pat. Nos. 5,149,321, 5,395,314, 5,584,804, 5,709,654 and 5,752,929 and U.S. patent application Ser. No. 08/484,601 to Klatz et al., which are hereby incorporated by reference. 
     Ideally organs would be procured in a manner which limits their warm ischemia time to essentially zero. Unfortunately, in reality, many organs, especially from non-beating heart donors, are procured after extended warm ischemia time periods (i.e. 45 minutes or more). The machine perfusion of these organs at low temperature has demonstrated significant improvement (Transpl Int 1996 Daemen). Numerous control circuits and pumping configurations have been utilized to achieve this objective and to machine perfuse organs in general. See, for example, U.S. Pat. Nos. 5,338,662 and 5,494,822 to Sadri; U.S. Pat. No. 4,745,759 to Bauer et al.; U.S. Pat. Nos. 5,217,860 and 5,472,876 to Fahy et al.; U.S. Pat. No. 5,051,352 to Martindale et al.; U.S. Pat. No. 3,995,444 to Clark et al.; U.S. Pat. No. 4,629,686 to Gruenberg; U.S. Pat. Nos. 3,738,914 and 3,892,628 to Thome et al.; U.S. Pat. Nos. 5,285,657 and 5,476,763 to Bacchi et al.; U.S. Pat. No. 5,157,930 to McGhee et al.; and U.S. Pat. No. 5,141,847 to Sugimachi et al., which are hereby incorporated by reference. 
     The cannulas and clamping methods according to the invention may be used in conjunction with apparatus and methods described in U.S. Pat. Nos. 6,014,864, 6,183,019, 6,241,945 and 6,485,450 to Owen, which are hereby incorporated by reference. While these apparatus and methods are related to organ recovery and transplantation, the cannulas and clamping methods according to the invention may also be used in various other medical procedures and with various other medical equipment where clamping with fluid flow is desired. Thus, the cannulas and clamping methods according to the invention are not limited to the applications described below in conjunction with the exemplary embodiments. 
       FIG. 5  shows a perfusion clamping apparatus or cannula  100  according to a first exemplary embodiment of the invention. The cannula  100  is capable of connecting one or more arteries of an organ to a perfusion machine or system (not shown), for example, by connection to tubing of the perfusion machine or system. All medical fluid contact surfaces are preferably formed of or coated with materials compatible with the medical fluid used, preferably non-thrombogenic materials. 
     The medical fluid for perfusion may be any suitable medical fluid. For example, it may be a simple crystalloid solution, or may be augmented with an appropriate oxygen carrier. The oxygen carrier may, for example, be washed, stabilized red blood cells, cross-linked hemoglobin, pegolated hemoglobin or fluorocarbon based emulsions. The medical fluid may also contain antioxidants known to reduce peroxidation or free radical damage in the physiological environment and specific agents known to aid in tissue protection. Further, the medical fluid may also include blood or blood products. 
     The cannula  100  is shown in  FIG. 5  in a closed or clamping condition and in  FIG. 6  in an exploded condition. The cannula  100  comprises a top portion  101 , a bottom portion  102 , a sealing ring  103  and compression straps  104 . Also, the cannula  100  may include a cannula mount in the from of a locating or positioning structure  117  that can be used to connect the cannula  100  to an organ platform or chair (not shown). While the relative terms “top” and “bottom” are used to refer to the various embodiments as shown in the Figs. throughout this application, it should be understood that the various parts may be otherwise oriented, and that the relative terms “top” and “bottom” are not limiting. 
     The top and bottom portions  101  and  102  seal to an aortic patch or other tissue by clamping the aortic patch or other tissue therebetween. The compression straps  104  are used to force the top portion  101  and the bottom portion  102  together and may be made of a resilient material, such as an elastomer. The sealing ring  103  may or may not be captured between the aortic patch or other tissue and the top portion  101  or the bottom portion  102 , or two sealing rings  103  may be present and captured between each of the top and bottom portions  101 ,  102  and the aortic patch or other tissue. The sealing ring  103  may be included or not, and may be incorporated into either or both sealing surfaces of the top and bottom surfaces  101  and  102 , described below. 
     The top portion  101  has a fitting  105  that is used to connect to a perfusion machine or other fluid source, for example, by tubing (not shown). The top portion  101 , or a portion thereof, may be constructed of a clear or translucent material that allows a user to visually check for air bubbles. Any air that is present in the cannula will collect at an upper portion  106  of the top portion  101 . 
     Various exemplary embodiments of the cannulas according to this invention provide a “lateral” fluid flow, i.e., a flow of fluid that is substantially perpendicular to the direction of fluid flow to and from the tissue to which the cannula is attached. For example, the one or more fittings of the cannula are oriented to have an axis of fluid flow that is substantially perpendicular to an axis of fluid flow into/out of the hole or lumen of the cannula. This “lateral” fluid flow arrangement allows the cannula to be connected to tubing of an organ transporter, for example, that is substantially in a single plane, for example, as described in the incorporated U.S. Provisional Applications Nos. 60/459,986 and 60/459,981). Further, multiple cannulas may be connected and even interconnected within substantially the same plane. 
     A second fitting  107  may be provided on the top portion  101  for priming and/or air bubble removal. The second fitting  107  comprises a port or valve for such purpose. The second fitting  107  may also be used to network multiple cannulas, for example, by connecting tubing in parallel, for example, by running a split infuse line to the first fitting of each cannula, or in series, for example, by connecting the first fitting of a cannula to the second fitting of another cannula. Standard luer geometry or other suitable structure may be used for fittings  105  and  107 . 
     As shown in  FIG. 7 , the top portion  101  has a top sealing surface  108 . The top sealing surface  108  may be made of a soft elastomer, such as, for example, SANTOPRENE® made by advanced Elastomer Systems. Any other suitable materials may be used as well, such as silicone or flexible polyvinylchloride (PVC) and the like. The top sealing surface  108  is shown in this embodiment as elliptical, although other suitable shapes, such as oval, circular and rectangular are also contemplated. The top sealing surface  108  may include ribs, ridges, cuts and/or protrusions that create a tortuous fluid path. The tortuous path serves to increase surface area by providing bends, turns and/or edges that increase the robustness of the seal and/or the likelihood of a sufficient seal. 
     The top portion  101  may include engagement members  109  that accept a free end of the compressions straps  104  and fixing members  110  that hold a portion of the compression straps  104  with the cannula  100  in a clamping condition. While the engagement members  109  are shown as slots in this embodiment, any suitable structure or technique, either known or hereafter developed, that provides attachment or retention of a free end of the straps  104  may be used. The top portion  101  may also have a pre-positioning structure  111 , as discussed further below. 
     While the engagement members  109  and fixing members  110  are shown as part of the top portion  101 , these members may be part of the bottom portion  102 . In other words, such features of the cannula  100  may be reversed. 
     As shown in  FIG. 8 , the bottom portion  102  has a bottom sealing surface  112  that mates with the top sealing surface  108 . The bottom sealing surface  112  may be made of a soft elastomer, as with the top sealing surface  108 . The bottom sealing surface  112  may also have ribs, ridges, cuts and/or protrusions that create a tortuous fluid path. 
     The bottom portion  102  may include flanges or other protrusions  113  near the bottom sealing surface  112 . The flanges  113  may be used to position the aortic patch or other tissue prior to assembly, for example, by clamping the aortic patch or other tissue to the flanges  113  with common surgical tools. 
     A hole  114  may be located in the bottom portion  102 . The aortic patch or other tissue is positioned by feeding the patch through the hole  114  and laying and/or spreading the patch across the bottom sealing surface  112 . The hole  114  may be designed to accept varying patch or other tissue sizes and/or patches or other tissues with multiple arteries. 
     The bottom portion  102  may include posts  115  that protrude outwardly. In use, the compression straps  104  can be wrapped around the posts  115 . Other suitable structures, either known or hereafter developed, that are capable of pressing and holding the top and bottom portions  101  and  102  together may be used in place of the compression straps  104 . For example, rigid clips or compliant springs may be used in place of the compression straps  104 . Such clips or springs may be made of any suitable material, such as metal or plastic. 
     The bottom portion  102  may include complementary pre-positioning structure  116  that complements the pre-positioning structure  111  of the top portion  101 . In the embodiment shown in  FIGS. 7-8 , the pre-positioning structure  111  is shown as a bar and the complementary pre-positioning structure  116  is shown as a pair of hooks or flanges. The hooks or flanges preferably engage the bar to allow the sealing surfaces  108  and  112  of the top and bottom portions  101  and  102  to remain parallel prior to closure and clamping. It should be understood that the structures  111  and  116  may be any suitable structures, either known or hereafter developed, that cooperate to provide pre-positioning of the top and bottom portions  101  and  102 . 
     As shown in  FIG. 8 , the locating or positioning structure  117  may be connected to the bottom portion  102 , although it may alternatively or additionally be connected to the top portion  101 . The positioning structure  117  is designed to position the cannula  100  relative to the organ and/or the organ platform or chair. The positioning structure  117  may also be designed to position the artery relative to the cannula  100  and/or the organ. The positioning structure  117  helps to hold the artery at a fixed tension and helps to keep the artery from getting twisted or stressed by securely positioning the cannula  100  onto the organ platform or chair. 
     The configuration and/or features of the positioning structure  117  will vary depending on the configuration of the organ platform or chair. For example, a post near a middle of the positioning structure  117  may provide a snap-fit with a corresponding structure of the organ platform or chair. Further, horizontal ribs or a washboard structure may engage or mate with a corresponding structure of the organ platform or chair. Other fastening arrangements including, but not limited to, clips, clamps, snaps, hook and loop fasteners (e.g., VELCRO® fasteners) and multi-part systems are contemplated as well. 
     An exemplary sealing ring  103  is shown in detail in  FIG. 9 . The sealing ring  113  may be shaped corresponding to the shape of the top and/or bottom portions  101  and  102 , particularly the top and bottom sealing surfaces  108  and  112 . The sealing ring  103  may be constructed of a soft material, such as SANTOPRENE® made by advanced Elastomer Systems, silicone or flexible polyvinylchloride (PVC) and the like, which allows the sealing ring  103  to surround and follow the contour of plaque or calcium deposits on the aortic patch or other tissue. The sealing ring  103  may also have details that help to locate the top portion  101  relative to the bottom portion  102  prior to closure. For example, undercuts in the sealing ring  103  may be arranged to mate with corresponding ribs formed on the top and/or bottom portions  101  and  102 . Alternatively, the sealing ring  103  may be made integral with the top and/or bottom portions  101  and  102 . 
     An exemplary compression strap  104  is shown in detail in  FIG. 10 . A free end of the compression strap  104  preferably has a shaped end or flange  118  that is configured to be engaged by engagement members  109  of the top portion  101 . The tension of the compression strap  104  may be varied, for example, by engaging one of a plurality of holes  119  to fixing members  110  of the top portion  101 . A textured surface, such as ridges, may be located at an end of the compression strap  104  (opposite the flange  118 ) to increase a user&#39;s grip for tensioning the compression strap  104 . As the compression straps  104  are tensioned in use, the top and bottom portions  101  and  102  of the cannula  100  are pulled together to create a seal. 
       FIG. 11  shows a perfusion clamping apparatus or cannula  200  according to a second exemplary embodiment of the invention. The cannula  200  is shown in  FIG. 11  in an open condition. The cannula  200  comprises a top portion  201  and a bottom portion  202 . Also, the cannula  200  may include a cannula mount or positioning structure  211  that can be used, for example, to connect the cannula  200  to an organ platform or chair (not shown). 
     In use, the aortic patch or other tissue associated with the organ is compressed between the top portion  201  and the bottom portion  202  to create a fluid seal to the patch or other tissue. A large surface area of the patch or other tissue is compressed, which allows a relatively low force to be used to achieve a suitable seal. The large sealing surface of this embodiment provides good contact to seal, for example, against aortic patches or other tissues with a hard plaque build-up. 
     As shown in  FIG. 12 , the top portion  201  has a fitting  203  that is used to connect to a perfusion machine or other fluid source, for example, by tubing (not shown). The top portion  201 , or a portion thereof, may be constructed of a clear or translucent material that allows a user to visually check for air bubbles. Any air that is present in the cannula  200  will collect at an upper portion of the top portion  201 . 
     A second fitting  204  may be provided on the top portion  201  for priming and/or air bubble removal. The second fitting  204  comprises a port or valve for such purpose. The second fitting  204  may also be used to network multiple cannulas, for example, by connecting tubing either in series or parallel, as discussed above. Standard luer geometry or other structure may be used for fittings  203  and  204 . 
     The top portion  201  has a top sealing surface  205 . The top sealing surface  205  may be made of a soft elastomer, such as, for example, SANTOPRENE® made by advanced Elastomer Systems, silicone or flexible polyvinylchloride (PVC) and the like. The top sealing surface  205  in the embodiment shown in  FIGS. 11-12  is a complex curved surface, for example, shaped like a football, being curved in both directions. Other suitable shapes, such as planar or cylindrical, are also contemplated. A cylindrically shaped surface may help to allow an aortic patch or other tissue to be fixed in its natural shape. 
     An opening  206  is provided in, preferably near the center of, the top sealing surface  205  to allow fluid flow. The opening  206  may be circular for example, for a single artery, or elliptical or oval, for example, to accommodate patches with multiple arteries, or may have other shapes. The top portion  201  preferably also has a plurality of protrusions or fingers  207  which may be used to secure the bottom portion  202 , as described below. 
     As shown in  FIG. 13 , the bottom portion  202  may comprise a preferably one-piece flexible part with a plurality of arms  209 . One or more holes  210  or other fixing structure may be provided in the arms  209 . The bottom portion  202  may preferably be made of a soft elastomer, such as, for example, SANTOPRENE® made by advanced Elastomer Systems, silicone or flexible polyvinylchloride (PVC) and the like. 
     Similar functionality may be accomplished with other arrangements, such as hinged clamps or suitable springs. The bottom portion  202  may comprise a rigid geometry that allows a snap fit either into or over the top portion  201 . The bottom portion  202  may alternatively comprise a hinged part that closes to lock onto the top portion  201 . A suitable spring may be designed to define a sealing surface and engage the top portion  201  to squeeze the aortic patch or other tissue to the top portion  201 . 
     A hole  208  is located in, preferably in a central zone of, the bottom portion  202 . The aortic patch or other tissue is positioned by feeding the patch or other tissue through the hole  208  and laying and/or spreading the patch or other tissue across the bottom portion  202 . The hole  208  may be cut to a desired size and/or shape to accommodate different patch or other tissue sizes and/or patches or other tissues with multiple arteries. The artery(ies) is/are preferably aligned with the opening  206  in the top portion  201  and the arms  209  are stretched upward to bring the top and bottom portions  201  and  202  together and apply a force to compress the patch therebetween. The holes  210  in the arms  209  are engaged on the fingers  207  of the top portion  201  to close the cannula  200 . Multiple holes  210  may be provided on each of the arms  209  to allow the user to adjust tension, or other fastening structure may be used (e.g., hook and loop features, buckles, clamps, etc.). 
     Further, various configurations, shapes and/or sizes of the bottom portion  202  may be provided, for example, for differing anatomies. For example, for the configuration shown in  FIG. 13 , different numbers of arms, lengths of arms, and or sizes and/or shapes of opening may be provided. 
     As shown in  FIG. 14 , the positioning structure  211  may include locating features  212  that may be used to position the cannula  200  and the artery of the organ with respect to the organ and/or the organ platform or chair. The positioning structure  211  preferably provides a cradle  213  that receive the cannula  200  such that the cannula  200  may rotate about one axis. This allows the cannula  200  to hold the artery straight while preventing over-tensioning of the artery. As shown in this embodiment, the cradle  213  may be formed by hooks that engage the top portion  201  of the cannula  200 . 
       FIG. 15  shows a perfusion clamping apparatus or cannula  300  according to a third exemplary embodiment of the invention. The cannula  300  is capable of connecting one or more arteries of an organ to a perfusion machine or system particularly when no aortic patch is available. This condition may arise due to difficult anatomy or living donors, when a portion of the aorta cannot be taken. Part of the cannula  300  is inserted directly into an artery and a suture, elastic band, vessel loops, adhesive, staple or other fastening mechanism is used to hold the artery in place. 
     The cannula  300  comprises a cannula body  301  and preferably also a cannula mount or positioning structure  308  that can be used to connect the cannula  300  to an organ platform or chair (not shown). 
     As shown in  FIG. 16 , the cannula body  301  has a fitting  302  that is used to connect to a perfusion machine or other fluid source, for example, by tubing (not shown). The cannula body  301 , or a portion thereof, may be constructed of a clear or translucent material that allows a user to visually check for air bubbles. Any air that is present in the cannula  300  will collect at an upper portion of the cannula body  301 . 
     A second fitting  303  may be provided on the cannula body  301  for priming and/or air bubble removal. The second fitting  303  comprises a port or valve for such purpose. The second fitting  303  may also be used to network multiple cannulas, for example, by connecting tubing either in series or parallel, as described above. Standard luer geometry or other structure may be used for fittings  302  and  303 . 
     The cannula body  301  also has a structure  304  that extends from the cannula body  301  and defines a lumen  307 . Also, the cannula body  301  may have a flange  305  that facilitates insertion of the structure  304  and/or suturing of the artery. 
     The lumen  307  allows fluid flow through the structure  304 . The structure  304  may be of various sizes to accommodate various anatomy and may have a securing feature  306  that cooperates with a fastening mechanism used to connect the artery to the cannula  300 . The securing feature  306  may be a substantially annular groove, as shown in  FIG. 16 , a substantially annular ridge or series of ridges, or any other structure that is designed to cooperate with any known or hereafter developed fastening mechanism. The structure  304  may be made of a soft elastomer, such as, for example, SANTOPRENE® made by advanced Elastomer Systems, silicone or flexible polyvinylchloride (PVC) and the like. 
     As shown in  FIG. 17 , the positioning structure  308  preferably has locating features  309  that may be used to position the cannula  300  and the artery of the organ, as described above. The positioning structure  308  provides a cradle  310  that preferably receives the cannula  300  such that the cannula  300  may rotate about one axis. This allows the cannula  300  to hold the artery straight while preventing over-tensioning of the artery. As shown in the embodiment of  FIG. 17 , the cradle  310  is formed by hooks that engage the cannula body  301 . 
       FIG. 18  shows a perfusion clamping apparatus or cannula  400  according to a fourth exemplary embodiment of the invention assembled with a cannula mount  500  and a platform  600 . The cannula  400  is capable of connecting one or more arteries of an organ to a perfusion machine or system (not shown), for example, by connection to tubing of the perfusion machine or system. 
     The cannula  400  is shown in  FIG. 18  in a closed or clamping condition and in  FIG. 19  in an exploded condition. The cannula  400  comprises a top portion  401 , a bottom portion  402 , a sealing ring  403  and compression straps  404 . As shown in  FIG. 18 , the cannula  400  is supported relative to the platform  600  via the cannula mount  500 . 
     The top and bottom portions  401  and  402  seal to an aortic patch or other tissue by clamping the aortic patch or other tissue therebetween. The compression straps  404  may be used to force the top portion  401  and the bottom portion  402  together and may be made of a resilient material, such as an elastomer. The sealing ring  403  may be captured between the aortic patch or other tissue and the top portion  401  and/or the bottom portion  402 . In the fourth embodiment, the sealing ring  403  is integral with the compression straps  404 . 
     The top portion  401  has a first fitting  405  that is used to connect to a perfusion machine or other fluid source, for example, by tubing (not shown). The first fitting  405  is in fluid communication with the chamber formed when the top and bottom portions  401  and  402  are brought together. The top portion  401 , or a portion thereof, may be constructed of a transparent or translucent material that allows a user to visually check for air bubbles. If the cannula  400  is oriented as shown, any air that is present in the cannula will collect at an upper portion  406  of the top portion  401 . 
     A second fitting  407  may be provided on the top portion  401  for priming and/or air bubble removal. The second fitting  407  may comprise a port or valve for such purpose. The second fitting  407  is in fluid communication with at least one of the first fitting  405  and the chamber formed when the top and bottom portions  401  and  402  are brought together. The second fitting  407  may also be used to network multiple cannulas, for example, by connecting tubing in parallel, for example, by running a split infuse line to the first fitting of each cannula, or in series, for example, by connecting the first fitting of a cannula to the second fitting of another cannula. Standard luer geometry or other suitable structure may be used for fittings  405  and  407 . 
     As shown in  FIG. 20 , the top portion  401  has a top sealing surface  408 . The top sealing surface  408  may be made of a soft elastomer, such as, for example, SANTOPRENE® made by advanced Elastomer Systems. Any other suitable materials may be used as well, such as silicone or flexible polyvinylchloride (PVC) and the like. The top sealing surface  408  is shown in this embodiment as elliptical, although other suitable shapes, such as oval, circular and rectangular are also contemplated. 
     The top portion  401  may include fixing members  410  that hold a portion of the compression straps  404  with the cannula  400  in a clamping condition. The fixing members  410  are shown as posts in  FIG. 20 ; however, any suitable structure that is capable of retaining the compression straps  404  may be used. 
     While the fixing members  410  are shown as part of the top portion  401 , these members may be part of the bottom portion  402 . In other words, such features of the cannula  400  may be reversed. 
     As shown in  FIG. 21 , the bottom portion  402  has a bottom sealing surface  412  that corresponds with the top sealing surface  408 . The bottom sealing surface  412  may be made of a soft elastomer, as with the top sealing surface  408 . The bottom sealing surface  412  may include a flange  413  that extends outwardly. The flange  413  may be used to position the aortic patch or other tissue prior to assembly, for example, by clamping the aortic patch or other tissue to the flange  413  with common surgical tools. 
     A hole  414  may be located in the bottom portion  402 . The aortic patch or other tissue is positioned by feeding the patch through the hole  414  and laying and/or spreading the patch across the bottom sealing surface  412 . The hole  414  may be designed to accept varying patch or other tissue sizes and/or patches or other tissues with multiple arteries. 
     The bottom portion  402  may include posts  415  that protrude outwardly. In use, the compression straps  404  can be wrapped around the posts  415 . As discussed above, other suitable structures, either known or hereafter developed, that are capable of pressing and holding the top and bottom portions  401  and  402  together may be used in place of the compression straps  404 . 
     The bottom portion  402  may include a complementary pre-positioning structure  416  that complements a pre-positioning structure  411  of the top portion  401 . In the embodiment shown in  FIGS. 18-19 , the pre-positioning structure  411  is shown as a bar and the complementary pre-positioning structure  416  is shown as a pair of hooks. The hooks preferably engage the bar to allow the sealing surfaces  408  and  412  of the top and bottom portions  401  and  402  to remain parallel prior to closure and clamping, for example, by providing both pivoting and linear movement of the top and bottom portions  401  and  402  relative to one another. It should be understood that the structures  411  and  416  may be any suitable structures, either known or hereafter developed, that cooperate to provide pre-positioning of the top and bottom portions  401  and  402 . 
     An exemplary sealing ring  403  is shown in detail in  FIG. 22 . The sealing ring  403  may be shaped corresponding to the shape of the top and/or bottom portions  401  and  402 , particularly the top and bottom sealing surfaces  408  and  412 . The sealing ring  403  may be constructed of a soft material, such as SANTOPRENE® made by advanced Elastomer Systems, silicone or flexible polyvinylchloride (PVC) and the like, which allows the sealing ring  403  to surround and follow the contour of plaque or calcium deposits on the aortic patch or other tissue. The sealing ring  403  may have a shape that is complementary to the shape of at least one of the top sealing surface  408  and the bottom sealing surface  412 . For example, as shown in  FIG. 22 , the sealing ring  403  may have a recess  417  that is shaped to snugly receive the top sealing surface  408 . 
     Exemplary compression straps  404  are shown in detail in  FIG. 22  as integral with the sealing ring  403 . This arrangement eliminates a need to separately position the straps  404  relative to other parts of the cannula  400  as well as a need to secure a free end of each compression strap  104  to the top or bottom portions of the cannula  400 . The tension of the compression straps  404  may be varied, for example, by engaging one of a plurality of holes  419  to fixing members  410  of the top portion  401 . A textured surface, such as ridges, may be located at an end of each compression strap  404  to increase a user&#39;s grip for tensioning the compression straps  404 . As the compression straps  404  are tensioned in use, the top and bottom portions  401  and  402  of the cannula  400  are pulled together to create a seal. 
     As discussed above, other suitable structures, either known or hereafter developed, that are capable of pressing and holding the top and bottom portions  401  and  402  together may be used in place of the compression straps  404 . For example, rigid clips or compliant springs may be used in place of the compression straps  404 . 
     As shown in  FIG. 18 , the cannula mount  500  is designed to position the cannula  400  relative to the organ (not shown) by supporting the cannula relative to the platform  600 . The cannula mount  500  helps to hold the artery of an organ at a fixed tension and helps to keep the artery from being twisted or stressed by securely positioning the cannula  400  in relation to the platform  600 . 
     Details of the cannula mount  500  according to the fourth exemplary embodiment are shown in  FIG. 23 . It should be understood that certain features described as located on the cannula mount  500  or the cannula  400  may be reversed and located on the other. Further, certain features described as located on the cannula mount  500  or the platform  600  may be reversed and located on the other. Thus, the particular arrangement is illustrative and not limiting. 
     The cannula mount  500  has a pair of substantially “U” or “C” shaped portions  502  that are adapted to removably engage a connection arm, such as the first and second fittings  405  and  407 , on the cannula  400 . The cannula mount  500  has an attachment feature  504  adapted to engage a separate support structure, such as the platform  600 . The separate support structure may be part of the platform  600  such that the cannula mount  500  is connected directly to the platform  600 . Alternatively, the separate support structure may be independently connected to the platform  600  such that the cannula mount  500  is connected indirectly to the platform  600 . 
     A feature of various exemplary embodiments of the cannula mount assembly according to this invention is that the cannula  400  may be positioned or located relative to the platform  600 . For example, as described below, the cannula mount  500  may be movably positionable on the separate support structure. Alternatively, the separate support structure may be movably positionable on the platform  600 . Thus, the height and/or position of the cannula  400  relative to the platform  600  may be adjusted to achieve a desired positional relationship between the cannula  400  and the platform  600  and/or an organ situated on the platform  600 . 
     It should be understood that while the cannula  400  and the cannula mount  500  are shown as separate elements, the cannula mount  500  may be integral with part of the cannula  400 . 
     The attachment feature  504  may be an open slot as shown in  FIG. 23  that is designed to receive a mounting portion  602  that extends from a base  604  of the platform  600 . 
     One side of the open slot  504  may be a resilient wall  506  that flexes to accommodate the mounting portion  602 . Thus, when the mounting portion  602  is fitted through the open slot  504 , the resilient wall  506  will press against the mounting portion  602  to hold the cannula mount  500  at a desired height above the base  604 . 
     The cannula mount  500  may include a “release mechanism.” For example, the resilient wall  506  may include a pair of substantially parallel extensions as shown in  FIG. 23 . In the exemplary embodiment, the resilient wall  506  will flex outward slightly when pressure is applied to a portion of the extensions, for example by applying a squeezing force to the extensions. The slight flexing of the resilient wall  506  may facilitate placement of the cannula mount  500  on the mounting portion  602  and may also facilitate movement of the cannula mount  500  on the mounting portion  602  to obtain a desired position of the cannula  400  relative to the platform  600 . It should be understood that any other arrangement that allows a user to temporarily flex the resilient wall  506  may be used as well. 
     As shown in  FIG. 20 , the fittings  405  and  407  may include flange portions  418  and  420 , respectively, that help a user to position the cannula  400  to locate the fittings  405  and  407  of the cannula  400  in the substantially “U” or “C” shaped portions  502 , as shown in  FIG. 18 . The flange portions  418  and  420  each may have one or more protrusions  422  on an inner surface  424 . The substantially “U” or “C” shaped portions  502  may have one or more complementary recesses  508  that are adapted to engage the protrusions  422  when the substantially “U” or “C” shaped portions  502  engage the fittings  405  and  407 . The engagement of the recesses  508  and the protrusions  422  restrict rotation of the fittings  405  and  407  relative to the substantially “U” or “C” shaped portions  502 . Thereby, rotation of the cannula  400  relative to the cannula mount  500  is restricted. 
     The configuration and/or features of the cannula mount  500  will vary depending on the configuration of the platform  600 . For example, the open slot arrangement is illustrative, and any suitable connection between the cannula mount  500  and the platform  600  may be used. 
     The above described apparatus and methods may be used for small or child organs as well as for large or adult organs with modification as needed. Further, while the apparatus and methods are described above with respect to transplanting organs, the apparatus and methods can also be used to provide an artificial blood supply to other tissues and cell cultures, for example, artificial placenta cell cultures, for growing/cloning tissues and/or organ(s). 
     As an example, use of the cannulas  100 ,  200 ,  300  and  400  will be described in connection with harvesting an organ, such as a kidney. An organ recovery surgeon will first inspect the kidney geometry and select an appropriate cannula based on the kidney geometry. The blood flow to the kidney(s) is stopped and the kidney or kidneys are flushed of blood. The kidney or kidneys are removed from the donor, if possible, still attached to the aorta. If the kidney or kidneys cannot be removed with the aorta attached, the surgeon may select a cannula according to the third exemplary embodiment. Otherwise, the surgeon may select a cannula according to one of the other embodiments. 
     If both kidneys are removed with the aorta, they are split at the aorta after removal. One of the kidneys is placed onto the platform or chair. The renal artery with the attached aortic cuff is threaded through the hole in the bottom portion of the cannula. The aortic cuff is spread across the sealing surface of the bottom portion of the cannula. Then, the top portion of the cannula is aligned with the bottom portion and the top and bottom portions are brought together and secured, for example, by compression straps or by connecting part of the bottom portion to the top portion. 
     The cannula is then positioned and attached to the platform or chair so that a flow of fluid through the renal artery can be established, preferably with the renal artery extended straight. 
     Before or after the cannula is properly positioned, an infuse line is connected to the first fitting of the cannula. The second fitting is then opened and flow of a desired fluid is initiated. In embodiments, air bubbles can be detected visually through the cannula and vented via the second fitting. Once all air has been removed, the second fitting is closed, the cannula is inspected for leaks and the cannula is adjusted, if necessary. The kidney is then perfused. 
     When an aortic patch is not available, the renal artery may be cut and the cannula inserted into the renal artery. Then, the renal artery is fastened to the cannula using an appropriate fastening mechanism, such as a suture. The cannula may be positioned and attached to the platform or chair and purged as described above. 
     The platform or chair may be placed or located in an organ cassette as discussed above, which is placed in a transport system that cools the organ cassette and the organ on the platform. The cannula may be connected to tubing of a perfusion system of the transport system and, if needed, purged after connection to the perfusion system. 
     The organ cassette allows an organ to be easily and safely moved between apparatus for perfusion, storing, analyzing and/or transporting the organ. The organ cassette may be configured to provide uninterrupted sterile conditions and efficient heat transfer during transport, recovery, analysis and storage, including transition between the transporter, the profusion apparatus and the organ diagnostic apparatus. The organ transporter allows for transportation of an organ over long distances. The organ transporter may be used for various organs, such as the kidneys, and may be adapted to more complex organs such as the liver, having multiple vascular structures, for example the hepatic and portal vasculatures of the liver. The organ transporter includes features of an organ perfusion apparatus, such as sensors and temperature controllers, as well as cassette interface features. The perfusion apparatus, transporter, cassette and organ diagnostic apparatus may be networked to permit remote management, tracking and monitoring of the location and therapeutic and diagnostic parameters of the organ or organs being stored or transported. The information systems may be used to compile historical data of organ transport and storage, and provide cross-referencing with hospital and United Network for Organ Sharing (UNOS) data on the donor and recipient. The systems may also provide outcome data to allow for ready research or profusion parameters and transplant outcomes. Various exemplary embodiments of the cannulas and the cannula mount assemblies according to this invention facilitate interconnection between an organ and the perfusion apparatus, transporter, cassette and organ diagnostic apparatus. 
     While the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations may be apparent to those skilled in the art. Accordingly, the exemplary embodiments of the invention as set forth herein are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of the invention.