Abstract:
A hydraulically actuated surgical instrument. The instrument may comprise a handle portion and a shaft. The shaft is mechanically coupled to the handle. The instrument may also include an end effector mechanically coupled to the shaft along its longitudinal axis. The end effector may comprise a surgical implement and a hydraulic device. At least a portion of the surgical implement may be translatable along a transverse axis, wherein the transverse axis is substantially perpendicular to the longitudinal axis of the shaft. Also, the hydraulic device may be positioned to be expandable toward the surgical instrument in a direction substantially parallel to the transverse axis of the shaft.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates in general to surgical instruments, and more particularly to endoscopic surgical instruments having a hydraulically actuated end effector.  
         [0002]     Endoscopic surgical instruments typically include an end effector positioned at the distal end of an elongate shaft and a handle at the proximal end of the elongate shaft allowing a clinician to manipulate the end effector. In use, the end effector is provided to a surgical site through a cannula of a trocar. At the surgical site, the end effector engages tissue in any number of ways to achieve a diagnostic or therapeutic effect. Endoscopic surgical instruments are often preferred over traditional open surgical instruments because they require smaller incisions that generally heal with less post-operative recovery time than traditional open surgery incisions. Because of this and other benefits of endoscopic surgery, significant development has gone into a range of endoscopic surgical instruments having end effectors that engage tissue to accomplish a number of surgical tasks. For example, end effectors have been developed to act as endocutters, graspers, cutters, staplers, clip appliers, access devices, drug/gene therapy delivery devices, ultrasound, RF, or laser energy devices, and other surgical instruments.  
         [0003]     Endoscopic surgical instruments must be configured to generate motion at the end effector in response to input from the handle or other input device, which is separated from the end effector by the narrow elongate shaft. This creates a considerable design challenge as the motions necessary at the end effector can be quite complex and may include motions transverse to the axis of the elongate shaft. One existing design includes a drive band extending from the instrument&#39;s handle to the end effector, through or around the elongate shaft. In response to inputs from the handle, the drive band is translated axially toward the end effector. End effector motions along the axis of the elongate shaft are derived directly from the drive band. Non-axial end effector motions, however, such as transverse stapling and clamping motions, must be derived by re-directing the axial drive motion. Often this is accomplished with reciprocating wedges or other mechanical devices. An example of this design is disclosed in U.S. Application Publication No. 2004/0232196 A1, the disclosure of which is herein incorporated by reference in its entirety.  
         [0004]     Surgical instruments utilizing the axial drive band design described above present a number of disadvantages. For example, friction between the axial drive band and the shaft generates significant energy loss. This energy loss is exacerbated in instruments having an articulating end effector as the axial drive band must then be translated through an articulation pivot. Mechanical re-directing devices cause additional energy losses because of their inefficiency. Mechanical re-directing devices are also bulky, adding to the overall diameter of the end effector and limiting its use in small surgical environments. Axial drive band devices also provide limited options for operating the end effector. For example, in a stapling instrument having staples driven by a reciprocating wedge, there is no way to fire the more distally located staples without firing the staples between, as the wedge sled must be translated through the positions of the proximally located staples first. It can then be appreciated that staple firing patterns available to reciprocal wedge staplers are quite limited.  
         [0005]     It is known to replace the axial drive band described above with axially directed hydraulic cylinders in the end effector. The cylinders provide axial motion to components within the end effector. Non-axial motions are still obtained by re-directing the axial motion provided by the cylinders with reciprocating wedge sleds or other mechanisms. Although this design eliminates the axial drive band and the associated frictional losses, it does not address other problems associated with mechanical re-directing devices such as, added bulk to the end effector, the inefficiencies of mechanical re-direction, and limited firing patterns.  
         [0006]     Accordingly there is a significant need for improved surgical instruments with smaller end effectors that are capable of use in smaller surgical sites. There is also a significant need for improved surgical instruments that can translate firing force to an end effector with increased efficiency. In addition, there is a significant need for improved surgical staplers that have a greater range of firing pattern options.  
       BRIEF SUMMARY OF THE INVENTION  
       [0007]     In accordance with one embodiment of the invention, there is provided a hydraulically actuated surgical instrument. The instrument may comprise a handle portion and a shaft mechanically coupled to the handle. The instrument may also include an end effector mechanically coupled to the shaft along its longitudinal axis. The end effector may comprise a surgical implement and a hydraulic device. At least a portion of the surgical implement may be translatable along a transverse axis, wherein the transverse axis is substantially perpendicular to the longitudinal axis of the shaft. Also, the hydraulic device may be positioned to be expandable toward the surgical instrument in a direction substantially parallel to the transverse axis of the shaft.  
         [0008]     In accordance with another embodiment of the invention, there is provided an end effector for use with a surgical fastening instrument. The end effector may be configured to drive surgical fasteners in a first direction, and may comprise a surgical fastener cartridge comprising a surgical fastener oriented in the first direction. The end effector may also comprise a fastener hydraulic device positioned to be expandable in the first direction toward the surgical fastener.  
         [0009]     In accordance with yet another embodiment of the invention, there is provided a surgical instrument comprising a valve unit, a first surgical implement, and a first hydraulic device. The first hydraulic device may be fluidically coupled to the valve unit and positioned to be expandable toward the first surgical implement. The surgical instrument may also comprise a second surgical implement and a second hydraulic device. The second hydraulic device may be fluidically coupled to the valve unit and positioned to be expandable toward the second surgical implement. The surgical instrument may also comprise a firing pattern control device in communication with the valve unit. The firing pattern control device may configure the valve unit to direct pressurized hydraulic fluid to the first and second hydraulic devices according to a firing pattern. 
     
    
     BRIEF DESCRIPTION OF THE FIGURES  
       [0010]     The accompanying drawings, which are incorporated in and constitute part of the specification, illustrate embodiments of the invention and, together with the general description of the invention given above, and the detailed description of the embodiments given below, serve to explain the principles of the present invention.  
         [0011]      FIG. 1  depicts a partially cut-away side elevation view of a surgical instrument in an open position according to various embodiments of the present invention;  
         [0012]      FIG. 2  depicts a cross-sectional side elevation detail view along the line  2 - 2  of  FIG. 1  of an end effector of the surgical instrument in an up or open position according to various embodiments of the present invention;  
         [0013]      FIG. 3  depicts a cross-sectional side elevation detail view along the line  2 - 2  of  FIG. 1  of an end effector of the surgical instrument in a down or closed position according to various embodiments of the present invention;  
         [0014]      FIG. 4  depicts a three dimensional view of the end effector at the distal end of the surgical stapling and severing instrument of  FIG. 1  with the anvil in the up or open position and portions of the cartridge largely removed exposing exemplary staple drivers and an exemplary cutting edge according to various embodiments of the present invention;  
         [0015]      FIG. 5  depicts a three dimensional view of an end effector at the distal end of the surgical stapling and severing instrument of  FIG. 1  with the anvil in the up or open position exposing the staple cartridge and cutting according to various embodiments of the present invention;  
         [0016]      FIG. 6  depicts a two dimensional top-down view of an elongate channel of the surgical stapling and severing instrument of  FIG. 1  according to various embodiments of the present invention;  
         [0017]      FIG. 7  depicts a two dimensional top-down view of a staple cartridge installed in an elongate channel with a portion of the staple cartridge removed to show exemplary staple drivers according to various embodiments of the present invention;  
         [0018]      FIG. 8  depicts a three dimensional view of the elongate channel of the surgical stapling instrument of  FIG. 1  showing a staple cartridge according to various embodiments of the present invention;  
         [0019]      FIG. 9  depicts a section view showing the cross-sectional relationship between the hydraulic bladders according to various embodiments of the present invention;  
         [0020]      FIG. 10  depicts a three dimensional, exploded view of the implement portion of the surgical stapling and severing instrument of  FIG. 1  according to various embodiments of the present invention;  
         [0021]      FIG. 11  depicts an un-inflated hydraulic bladder staple driver for use in a surgical instrument according to various embodiments of the present invention;  
         [0022]      FIG. 12  depicts an inflated hydraulic bladder staple driver for use in a surgical instrument according to various embodiments of the present invention;  
         [0023]      FIG. 13  depicts a hydraulic cylinder staple driver for use in a surgical instrument according to various embodiments of the present invention;  
         [0024]      FIG. 14  depicts a hydraulic staple driving assembly for use in a surgical instrument according to various embodiments of the present invention;  
         [0025]      FIG. 15  depicts a side view of a hydraulic staple driving assembly for use in a surgical instrument according to various embodiments of the present invention;  
         [0026]      FIG. 16  depicts a top view of a hydraulic staple driving assembly for use in a surgical instrument according to various embodiments of the present invention;  
         [0027]      FIG. 17  depicts a side view of a hydraulic staple driving assembly for use in a surgical instrument according to various embodiments of the present invention;  
         [0028]      FIG. 18  depicts the distal end of a surgical stapling and severing instrument having an articulating end effector shown in the down or closed position according to various embodiments of the present invention;  
         [0029]      FIG. 19  depicts a three dimensional view of a hydraulic surgical instrument according to various embodiments of the present invention;  
         [0030]      FIG. 19A  depicts a schematic diagram of a hydraulic system for use in a surgical instrument according to various embodiments of the present invention;  
         [0031]      FIG. 20  depicts a side elevation view in centerline section of the surgical stapling and severing instrument of  FIG. 1  with the end effector in a partially closed but unclamped position gripping tissue according to various embodiments of the present invention;  
         [0032]      FIG. 21  depicts a partially cut-away side elevational view of the surgical stapling and severing instrument of  FIG. 1  in the closed or clamped position according to various embodiments of the present invention;  
         [0033]      FIG. 22  depicts a side elevation view in centerline section of the distal end of the surgical stapling and severing instrument of  FIG. 1  in the closed or clamped position with tissue properly compressed according to various embodiments of the present invention;  
         [0034]      FIG. 23  depicts a partially cut-away side elevation view of the surgical stapling and severing instrument of  FIG. 1  in a partially fired position according to various embodiments of the present invention;  
         [0035]      FIG. 24  depicts a side elevation view in centerline section of the distal end of the surgical stapling and severing instrument of  FIG. 1  in a partially fired position according to various embodiments of the present invention;  
         [0036]      FIG. 25  depicts a partially cut-away side elevation view of the surgical stapling and severing instrument of  FIG. 1  in a fully fired position according to various embodiments of the present invention; and  
         [0037]      FIG. 26  depicts a side elevation view in centerline section of the distal end of the surgical stapling and severing instrument of  FIG. 1  in a fully fired position according to various embodiments of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0038]     The terms “proximal” and “distal” are used herein with reference to a clinician gripping a handle of an instrument. For example, referring to the surgical instrument  10  shown in  FIG. 1 , the end effector  12  is distal with respect to the more proximal handle portion  20 . It will be further appreciated that for convenience and clarity, spatial terms such as “vertical” and “horizontal” are used herein with respect to the drawings. However, surgical instruments are used in many orientations and positions, and these terms are not intended to be limiting and absolute.  
         [0039]     As used herein, the term “surgical implement” refers to a component or set of components configured to engage tissue to accomplish a surgical task. Examples of surgical implements include, but are not limited to: endocutters, graspers, clamps, cutters, staplers, other surgical fasteners, clip appliers, probes or access devices, drug/gene therapy delivery devices, energy devices such as ultrasound, RF, or laser devices, etc.  
         [0040]     As used herein, the term “surgical fastener” refers to any kind of fastener used in surgical settings including, for example, a staple, a hernia tacker, etc. As used herein, the term “surgical fastener” may also refer to a device for deploying a staple, hernia tacker, etc.  
         [0041]     As used herein, the term “fluidically coupled” means that the elements are coupled together with an appropriate line or other means to permit the passage of pressurized fluid medium, air, etc. therebetween. As used herein, the term “line” as used in “supply line,” “hydraulic line” or “return line” refers to an appropriate fluid passage formed from conduit, pipe, tubing, etc. for transporting pressurized hydraulic fluid from one component to another.  
         [0042]     As used herein, the term, “hydraulic fluid” refers to any fluid suitable for use in a hydraulic system. Non-limiting examples of hydraulic fluids include oil, air, etc. In one non-limiting embodiment, hydraulic fluids may be biocompatable fluids including, for example, glycerine oil, saline, etc.  
         [0043]     Turning to the figures, the surgical instrument  10  of  FIG. 1  includes a handle portion  20  and an implement portion  22 . The implement portion  22  includes a shaft  23  and an end effector  12 . The end effector  12  shown in  FIG. 1  is configured to act as an endocutter including surgical implements for clamping, stapling and severing, however, it will be appreciated that the advantages of the present invention may be achieved with end effectors (not shown) including alternate and/or additional surgical implements.  
         [0044]     Referring back to the non-limiting embodiment shown in  FIG. 1 , the handle portion  20  of the instrument  10  includes a pistol grip  24  toward which a closure trigger  26  is pivotally drawn by a clinician to cause clamping, or closing, of the anvil  18  toward the elongate channel  16  of the end effector  12 . A firing trigger  28  is farther outboard of the closure trigger  26  and is pivotally drawn by the clinician to cause the stapling and severing of clamped tissue in the end effector  12 .  
         [0045]     The force necessary to cause the closure, stapling, and severing of tissue may be provided by a plurality of hydraulic devices (not shown in  FIG. 1 ) located in the end effector  12  such as, for example, bladders, cylinders, etc. In various embodiments, the hydraulic devices may be supplied with pressurized hydraulic fluid via hydraulic line bundle  306  extending from handle  20  of the instrument  10  to the end effector  12 , for example, through the elongate shaft  23 .  
         [0046]      FIGS. 2-5  show views of the end effector  12  configured to perform clamping, severing and stapling of tissue according to various embodiments the present invention. The end effector  12  may include anvil  18  and elongate channel  16  configured to receive a staple cartridge  37 . The anvil  18  may pivot towards the elongate channel  16  and staple cartridge  37  about anvil pivot  14 .  FIG. 2  shows the anvil  18  in an open position, while  FIG. 3  shows the anvil  18  in a pivoted or closed position.  
         [0047]     Force necessary to pivot or drive the anvil  18 , in various embodiments, may be provided by closure sleeve  32 . For example, when the clinician actuates closure trigger  26 , the closure sleeve  32  may be translated distally toward the end effector driving the anvil  18  into the closed position shown in  FIG. 3 . When the closure trigger  26  is released, the closure sleeve  32  may be translated proximally away from the end effector  12 . The instrument  10  may include a spring or other energy storage device causing the anvil  18  to return to the open position shown in  FIG. 2  when the closure sleeve  32  is retracted. Force may be transferred from the closure trigger  26  to the closure sleeve  32  by any mechanism known in the art including, for example, a gear system, an electric motor, a hydraulic device, etc.  
         [0048]     Referring back to  FIG. 2 , the end effector  12  may include a transversely presented cutting edge  326 . The cutting edge  326  may be driven by a hydraulic cutting bladder  322  positioned below the cutting edge  326 . A cutting bar  324  may be positioned between the cutting bladder  322  and cutting edge  326 . In various embodiments, the cutting bladder  322 , bar  324  and edge  326  may be fastened to one another. It will be appreciated that the hydraulic cutting bladder  322 , in various non-limiting embodiments, may be replaced by any kind of hydraulic device including, for example, a hydraulic cylinder. In response to a clinician actuating the firing trigger  28 , the hydraulic cutting bladder  322  may expand in a transverse direction. This drives the cutting edge  326 , causing it to move through the elongate channel  16  and staple cartridge  37  in a transverse direction and sever any tissue (not shown) present between the anvil  18 , staple cartridge  37  and elongate channel  16 , for example, as described in more detail below with reference to  FIGS. 20-26 .  
         [0049]     Referring again to  FIG. 3 a  cross sectional view of the end effector  12  is shown including staples  222  and staple drivers  220  according to various embodiments. A plurality of staples  222  and staple drivers  220  are shown positioned adjacent the cutting edge  326 . Each staple driver  220  may be positioned below one, or a plurality of staples  222  included in the staple cartridge  37 . A staple hydraulic bladder  327  may be positioned below the staple drivers  220 . The staple hydraulic bladder  327  may be expandable in a transverse direction toward staple drivers  220 . The staple hydraulic bladder  327  may expand in response to the actuation of the firing trigger  28  by the clinician. Expansion of the staple hydraulic bladder  327  forces the staple drivers  220  and staples  222  toward staple forming pockets (not shown in  FIG. 3 ) present in the anvil  18 , thus driving the staples.  
         [0050]      FIG. 4  shows a three dimensional view of the end effector  12  of the instrument  10  with a portion of the staple cartridge  37  removed to expose features of the elongate channel  16 , such as recesses  212 ,  214 , and components of the staple cartridge  37 , such as staple drivers  220 , in their unfired position. The cutting edge  326  is shown at its unfired position, located in the center of staple drivers  220 .  FIG. 4  also shows tissue stops  244  located at the proximal end of the anvil  18 . Tissue stops  244  may, in various embodiments, prevent tissue from coming into contact with components of the anvil pivot  14 , causing the end effector  12  to jam.  
         [0051]      FIG. 5  depicts a three dimensional view of the end effector  12  in an open position with a staple cartridge  37  installed in the elongate channel  16 . On a lower surface  200  of the anvil  18 , a plurality of stapling forming pockets  202  are arrayed to correspond to a plurality of staple apertures  204  in an upper surface  206  of the staple cartridge  37 . Each aperture  204  may correspond to an individual staple  222  located within the staple cartridge  37  immediately below the aperture  204  as shown in  FIG. 3 . Slot  49 , positioned in the middle of the staple cartridge  37 , may enclose the cutting edge  326  (not shown in  FIG. 5 ). The staple cartridge  37  may be snap-fit into the elongate channel  16 . For example, extension features  208 ,  210  of the staple cartridge  37  engage recesses  212 ,  214  (shown in  FIG. 4 ) of the elongate channel  16 .  
         [0052]     In various embodiments, staples  222  included in the end effector  12  may be driven according to one or more staple zones, with each staple zone able to be fired or driven separately.  FIGS. 6-8  show a non-limiting zoned embodiment including six staple zones, with each staple zone including one hydraulic device and one staple driver configured to drive a plurality of staples. For example, a right distal staple zone includes right distal staple bladder  332  (shown in  FIG. 6 ), and right distal staple driver  370  (shown in  FIG. 7 ). It will be appreciated that various non-limiting embodiments of the present invention may include more or fewer than six staple zones depending on the application, with each zone including as many or as few staples as desired. It will also be appreciated that that individual staple zones according to various embodiments of the present invention may include multiple staple bladders and/or staple drivers.  
         [0053]     Referring back to  FIG. 6 , a top down view of the elongate channel  16  is shown including six hydraulic staple bladders  328 ,  330 ,  332 ,  334 ,  336  and  338 . Each of the bladders may correspond to one of the six zones of staples. The bladders  328 ,  330 ,  332 ,  334 ,  336 ,  338  as well as cutting bladder  322  (positioned below cutting bar  324  in  FIG. 10 ) may be individually provided with pressurized hydraulic fluid through respective hydraulic lines  340 ,  342 ,  344 ,  346 ,  348 ,  350 ,  352  included in hydraulic line bundle  306 . Accordingly, in various embodiments, each of bladders  328 ,  330 ,  334 ,  336 ,  338  and  322  may drive associated surgical implements individually or according to a firing pattern.  
         [0054]      FIG. 7  shows a top down view of the elongate channel  16  and staple cartridge  37  with the upper surface  206  of the staple cartridge  37  removed to show staple drivers  370 ,  372 ,  374 ,  376 ,  378 ,  380 . Each staple driver may correspond to one of the six staple zones. Also, each staple driver  370 ,  372 ,  374 ,  376 ,  378 ,  380  is positioned above the staple bladder  328 ,  330 ,  332 ,  334 ,  336 ,  338  (shown in  FIG. 10 ) corresponding to the same staple zone. For example, right distal staple bladder  332  is positioned above the right distal staple driver  370 . It will be appreciated that it is not necessary to have only one staple driver corresponding to each staple bladder  328 ,  330 ,  332 ,  334 ,  336 ,  338 . For example, in one non-limiting embodiment, a staple driver  220  may be provided for each individual staple  222 .  
         [0055]      FIG. 8  shows an exploded three dimensional view of the elongate channel  16  with staple cartridge  37  implementing the staple zone scheme shown in  FIGS. 6 and 7 . The staple cartridge  37  may include staple recesses  354 ,  356 ,  358 ,  360 ,  362 ,  364 . Each staple recess may house staples  222  (not shown in  FIG. 8 ) and one of staple drivers  370 ,  372 ,  374 ,  376 ,  378  (not shown in  FIG. 8 ). When the staple cartridge  37  is installed in the elongate channel  16 , each staple recess, including staples  222  and the staple drivers described above, may align with at least one staple bladder  328 ,  330 ,  332 ,  334 ,  336 ,  338 . When the staple bladders  328 ,  330 ,  332 ,  334 ,  336 ,  338  are inflated, they may extend into the staple recesses  354 ,  356 ,  358 ,  360 ,  362 ,  364 , creating a transverse force against the staple drivers  370 ,  372 ,  374 ,  376 ,  378 , which in turn drive the staples  222 .  FIG. 8  also shows that the staple cartridge  37  may include channels  366  for receiving hydraulic lines  340 ,  342 ,  344 ,  346 ,  348 ,  350 ,  352 , shown in  FIG. 10 . The channels  366  prevent the various hydraulic lines from being pinched between the staple cartridge  37  and the elongate channel  16 .  
         [0056]      FIG. 9  shows a cross-sectional view of the end effector  12  showing the configuration of bladders  328 ,  334 ,  322 ,  338  and  334  according to various embodiments. Bladder  328  is shown positioned below staple driver  370 . Inflating bladder  328  causes a transverse force to be exerted on the driver  370 , which may drive the staple  222 . The other staple bladders  334 ,  338  and  334  shown in  FIG. 9  may operate in a similar fashion. Cutting bladder  322  may also create a transverse force when inflated. The transverse force may cause cutting bar  324  to rise transversely, pushing cutting edge  326  transversely through any tissue (not shown) present in the end effector  12 .  
         [0057]      FIG. 10  shows the implement portion  22  of the surgical stapling and severing instrument  10  in disassembled form. The staple cartridge  37  is shown comprised of a cartridge body  216 , staple drivers  370 ,  372 ,  374 ,  376 ,  378 ,  380 , cutting edge  326  and staples  222 . When assembled, the cartridge body  216  holds the staple drivers  370 ,  372 ,  374 ,  376 ,  378 ,  380  and staples  222 . When the implement portion  22  is assembled, cutting bladder  322 , cutting bar  324  and cutting edge  326  may be positioned along the elongate channel  16  as shown. Staple bladders  328 ,  330 ,  332 ,  334 ,  336 ,  338  may also be positioned along the elongate channel  16  and may be used to drive staples  222 , for example, according to the zoned scheme described above. The staple cartridge  37  may be placed in the elongate channel  16  such that the cutting bladder  322 , cutting bar  324  and cutting edge  326  align with channel  49  and such that lines of staples  222  and drivers  370 ,  372 ,  374 ,  376 ,  378 ,  380  align with bladders  328 ,  330 ,  332 ,  334 ,  336 ,  338 .  
         [0058]     The embodiments described above show staples  222  resting on a staple bladder  327 , or staple bladders  328 ,  330 ,  332 ,  334 ,  336 ,  338 , with various staple drivers  220  therebetween. It will be appreciated, however, that in various non-limiting embodiments, staples may be hydraulically driven utilizing other mechanisms. For example,  FIGS. 11-12  show a staple  222  resting directly on a staple bladder  504  (e.g., without a staple driver). A hydraulic line  506  may provide pressurized hydraulic fluid to the bladder  504 , for example, in response to the actuation of the firing trigger  28  by the clinician. When pressurized hydraulic fluid is provided to the staple bladder it may expand transversely, as shown in  FIG. 12 . The transverse motion of the staple bladder  504  may force the staple  222  against staple forming pocket  202 , thereby driving the staple  222 . The assembly shown in  FIGS. 11-12  may be incorporated into the end effector  12 , for example, by placing a staple bladder or bladders  504  along the elongate channel  16 . It will be appreciated that in various embodiments, each bladder  504  may drive one or a plurality of staples  222 .  
         [0059]      FIG. 13  shows another non-limiting embodiment showing an additional mechanism including a staple driving cylinder  510 . The cylinder  510  may include a piston  512 . The staple  222  may rest on the piston  512 . A staple driver (not shown in  FIG. 13 ) may or may not be present between the piston  512  and the staple  222 . A hydraulic line  514  may provide pressurized hydraulic fluid, causing the piston  512  to extend. In response, the piston  512  may drive staple  222  into contact with staple pocket  202  as described above. In various embodiments, the cylinder  510  may drive one or a plurality of staples  222 . It will be appreciated that the assembly shown in  FIG. 13  may be incorporated into end effector  12  by placing one or more cylinders  510  along the elongate channel  16 .  
         [0060]      FIG. 14  shows an exploded view of another non-limiting exemplary embodiment for hydraulically driving staples according to various embodiments of the present invention. Staples  222  are shown resting on staple driver  517  which in turn rests on deployment plate  516 . Guidance rails  518  are shown surrounding the deployment plate  516 . When provided with pressurized hydraulic fluid, bladder  522  may expand transversely. This may cause the deployment plate  516  to expand transversely along guidance rails  518 , driving staples  222 . The guidance rails  518  may insure that deployment plate  516  expands in a transverse direction. In one non-limiting embodiment, staples  222  may rest directly on the deployment plate  516  (e.g., without drivers  517 ). It will be appreciated that the assembly shown in  FIG. 14  may be incorporated into the end effector  12  by placing one or more bladders  522 , guidance rails  518 , and deployment plates  516  along the elongate channel  16 .  
         [0061]      FIGS. 15-17  show yet another non-limiting exemplary embodiment for hydraulically driving staples according to various embodiments.  FIG. 15  shows a hydraulic bladder  524  mated to a rigid deployment plate  526 . The deployment plate  526  may include a series of apertures  528 . Each aperture may correspond to one or more staples. When pressurized hydraulic fluid is applied to the bladder  524 , it may expand transversely through the apertures  528  in the deployment plate  526 . The portions of the bladder  524  extending through apertures  528  may provide a transverse driving force to one or more staples  222 , as shown in  FIG. 17 .  
         [0062]     In various embodiments, the instrument  10  may include an articulating end effector  12  as shown in  FIG. 18 . The end effector  12  may pivot away from the axis of the elongate shaft  23  at articulation pivot  368 . It can be seen that the hydraulic line bundle  306  passes through articulation pivot  368  with ease.  
         [0063]      FIG. 19  shows an embodiment of the instrument  10  equipped with a hydraulic system  321  according to various embodiments. A hydraulic pump  302  may generate pressurized hydraulic fluid when firing trigger  28  and/or the closure trigger  26  is actuated. The hydraulic pump  302  may be any kind of device suitable for pressurizing hydraulic fluid including, for example, a cylinder, a bladder, etc. In various embodiments, an additional pump (not shown) may be included, for example, to drive the anvil  18  in response to actuation of the closure trigger  26 . Pressurized hydraulic fluid generated by the hydraulic pump  302  may be provided to valve unit  304  which may in turn provide the fluid to various bladders and/or cylinders (not shown in  FIG. 19 ) located in the end effector  12  via hydraulic line bundle  306 . Valve unit  304  may include any kind of valve or valves suitable for controlling and directing the flow of hydraulic fluid. In various non-limiting embodiments, the valve unit may include electrically actuated valves, such as, for example, piezo valves or Electro Active Polymer (EAP) valves which may be configured in response to an electrical signal.  
         [0064]     One embodiment of the hydraulic system  321  that may be employed to control the end effector  12  is depicted in schematic form in  FIG. 19A . In this non-limiting embodiment, the pump  302  is embodied as a conventional hydraulic pump assembly that includes a fluid reservoir  432 . In one embodiment, the pump  302  is powered by a battery  434  supported within the handle. In another non-limiting embodiment, the pump  302  may be powered by the same battery  320  powering the control circuit  318  described below. It will be appreciated that the pump  302  could also be powered by other means, such as by alternating current. In one non-limiting embodiment, the pump  302  may be a hydraulic bladder or cylinder powered by mechanical force derived from one or more of the triggers  26 ,  28 . The pump  302  may be fluidically coupled to the reservoir  432  by supply line  436  that may have a conventional check valve  438  therein. See  FIG. 19A .  
         [0065]     In one embodiment, a discharge line  440  attached to the discharge port  431  of the pump  302  is piped to a manifold  442  that has designated supply lines for each bladder coupled thereto. For example, in the embodiment depicted in  FIG. 19A , a supply line  444  is coupled to bladder  328  and has a control valve  460  therein for controlling the flow of pressurized fluid through the line  444  to bladder  328 . Supply line  446  is coupled to bladder  330  and has a control valve  462  therein. Supply line  448  is coupled to bladder  332  and has a control valve  464  therein. Supply line  450  is coupled to bladder  334  and has a control valve  466  therein. Supply line  452  is coupled to bladder  336  and has a control valve  468  therein. Supply line  454  is coupled to bladder  338  and has a control valve  470  therein. Supply line  456  is coupled to cutting bladder  322  and has control valve  472  therein. A return valve  478  is provided to permit the fluid to return from the bladders into the manifold line  442  and through a return line  459  that is attached to the manifold  442  and the reservoir  432 . As can be seen in  FIG. 19A , the return line  459  may have a return valve  478  therein. Valves  460 ,  462 ,  464 ,  466 ,  468 ,  470 ,  472 ,  474 ,  478  comprise a valve unit, generally designated as  304  and described above.  
         [0066]     The valve unit  304  may be configured by a control circuit  318  in response to input received from input buttons, such as buttons  308 ,  310 ,  312 ,  314 , and/or  316 . A battery  320  may provide electrical power to the control circuit  318  and buttons  308 ,  310 ,  312 ,  314 ,  316 . The control circuit  318  may be any kind of circuit capable of generating signals for configuring valve unit  304  in response to input from buttons  308 ,  310 ,  312 ,  314 ,  316 . In one non-limiting embodiment, the control circuit  318  may include a microprocessor and other related components including Random Access Memory (RAM), Read Only Memory (ROM), etc. In other non-limiting embodiments, the control circuit  318  may include various logical circuit elements.  
         [0067]     The control circuit  318  may configure the valves in response to input buttons  308 ,  310 ,  312 ,  314 ,  316 . In one non-limiting embodiment, each input button  308 ,  310 ,  312 ,  314 ,  316  may correspond to a particular surgical implement, or portion of a surgical implement, included in the end effector  12 . For example, button  308  may correspond to a cutter while buttons  310 ,  312 ,  314 ,  316  may each correspond to a zone of staples (not shown in  FIG. 2 ). Selecting the button  308 ,  310 ,  312 ,  314 ,  316  corresponding to a surgical implement may cause the control circuit  318  to configure the valve unit  304  such that a hydraulic device corresponding to the function is fired when firing trigger  28  is depressed, driving the corresponding surgical implements. Multiple buttons may be selected to create firing patterns including more than one implement. In other non-limiting embodiments, each input button  308 ,  310 ,  312 ,  314 ,  316  may represent a pre-determined firing order and/or pattern. For example, selecting a button  308 ,  310 ,  312 ,  314 ,  316  may cause the control circuit  318  to configure the valve unit  304  such that hydraulic devices corresponding to particular surgical implements are fired when the firing trigger  28  is depressed. It will be appreciated that various embodiments may have more or fewer input buttons than are shown.  
         [0068]     In various non-limiting embodiments, control circuit  318  may configure the valve unit  304  to introduce a delay to the driving of one or more surgical implements included in the end effector  12 . For example, it may be desirable to drive a cutting implement and then delay for a predetermined time before driving one or more zones of a stapling implement. The delay may be accomplished according to any suitable method. In one non-limiting embodiment, the control circuit  318  may configure the valve unit  304  to open a path for hydraulic fluid between the hydraulic pump  302  and a first surgical implement included in the end effector  12 . When the firing trigger  28  is actuated, the pump  302  may generate pressurized hydraulic fluid, which drives the first surgical implement. The control circuit  318  may sense when the first surgical implement is driven (e.g., by sensing the position of the firing trigger  28 ), for example using sensor  405  shown in  FIG. 19A . When the first surgical implement is driven, the control circuit  318  may begin a timer that counts off a predetermined delay time. At the expiration of the predetermined delay time, the control circuit  318  may configure the valve unit  304  to provide the pressurized hydraulic fluid to a second surgical implement. Hydraulic pressure generated at the actuation of the firing trigger  28  may be sufficient to drive the second surgical implement, or in various embodiments, the hydraulic pump  302  may be utilized to generate additional hydraulic pressure.  
         [0069]     In use, the surgical stapling and severing instrument  10  is used as depicted in  FIGS. 1, 2 , and  20 - 26 . In  FIGS. 1-2 , the instrument  10  is in its start position, having had an undriven, fully loaded staple cartridge  37  snap-fitted into the distal end of the elongate channel  16 . Both triggers  26 ,  28  are forward and the end effector  12  is open, such as would be typical after inserting the end effector  12  through a trocar or other opening into a body cavity. The instrument  10  is then manipulated by the clinician such that tissue  248  to be stapled and severed is positioned between the staple cartridge  37  and the anvil  18 , as depicted in  FIG. 20 .  
         [0070]     With reference to  FIGS. 21-22 , next, the clinician moves the closure trigger  26  proximally until positioned directly adjacent to the pistol grip  24 , locking the handle portion  20  into the closed and clamped position. The retracted cutting edge  326  in the end effector  12  does not impede the selective opening and closing of the end effector  12 , but rather resides along the elongate channel  16 , positioned in the slot  49  of the staple cartridge  37 . In response to the actuation of the closure trigger  26 , the anvil  18  may be driven to pivot along anvil pivot  14 .  
         [0071]     With reference to  FIGS. 23-24 , after tissue clamping has occurred, the clinician moves the firing trigger  28  proximally causing hydraulic fluid to be pressurized, for example, by hydraulic pump  302 . When the instrument is configured to cut, the hydraulic pressure may cause cutting bladder  322  to inflate, forcing cutting bar  324  through slot  49  and into contact with cutting edge  326 , which may sever the tissue  248 . When the instrument is configured to staple, the hydraulic pressure may cause one or more of the staple bladders  328 ,  330 ,  332 ,  334 ,  336 ,  338  (not shown in  FIG. 24 ) to inflate, exerting a vertical force on drivers  220  which in turn drive staples  222 . With reference to  FIGS. 25-26 , the clinician continues moving the firing trigger  28  until brought proximal to the closure trigger  26  and pistol grip  24 . Thereby, all of the ends of the staples  222  are bent over as a result of their engagement with the anvil  18 . The process is completed by releasing the firing trigger  28  and by then depressing the release button  30  while simultaneously squeezing the closure trigger  26  to open the end effector  12 .  
         [0072]     While the present invention has been illustrated by description of several embodiments and while the illustrative embodiments have been described in considerable detail, it is not the intention of the applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications may readily appear to those skilled in the art.  
         [0073]     For example, although the embodiments described above have advantages for an endoscopically employed surgical severing and stapling instrument  10 , a similar embodiments may be used in other clinical procedures. It is generally accepted that endoscopic procedures are more common than laparoscopic procedures. Accordingly, the present invention has been discussed in terms of endoscopic procedures and apparatus. However, use herein of terms such as “endoscopic”, should not be construed to limit the present invention to a surgical instrument for use only in conjunction with an endoscopic tube (i.e., trocar). On the contrary, it is believed that the present invention may find use in any procedure where access is limited to a small incision, including but not limited to laparoscopic procedures, as well as open procedures.  
         [0074]     For yet another example, although an illustrative handle portion  20  described herein is operated hydraulically in response to input from a clinician, it is consistent with aspects of the invention for some or all of the functions of a handle portion to be powered by other means (e.g., pneumatic, electromechanical, ultrasonic, mechanical, etc.). Furthermore, controls of each of these functions may be manually presented on a handle portion or be remotely controlled (e.g., wireless remote, automated remote console, etc.).  
         [0075]     Any patent, publication, or other disclosure material, in whole or in part, that is said to be incorporated by reference herein is incorporated herein only to the extent that the incorporated material does not conflict with existing definitions, statements, or other disclosure material set forth in this disclosure. As such, and to the extent necessary, the disclosure as explicitly set forth herein supersedes any conflicting material incorporated herein by reference. Any material, or portion thereof, that is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material set forth herein will only be incorporated to the extent that no conflict arises between that incorporated material and the existing disclosure material.