Patent Publication Number: US-2023149065-A1

Title: Vessel sealer with plasma blade dissection electrode

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of U.S. Provisional Application Ser. No. 63/279,612 filed Nov. 15, 2021, the entire contents of which being incorporated by reference herein. 
    
    
     FIELD 
     The present disclosure relates to surgical instruments and, more particularly, to plasma blades, electrosurgical instruments including plasma blades, and methods of manufacturing plasma blades. 
     BACKGROUND 
     A surgical forceps is a pliers-like instrument that relies on mechanical action between its jaw members to grasp, clamp, and constrict tissue. Electrosurgical forceps utilize both mechanical clamping action and energy to heat tissue to treat, e.g., coagulate, cauterize, or seal, tissue. Prior to tissue treatment, a second device or possibly the same forceps may be utilized to dissect tissue layers or otherwise separate tissue. Once the tissue is separated, the tissue may be treated and, once treated, the surgeon has to accurately sever the treated tissue. 
     Accordingly, many electrosurgical forceps are designed to include a tip that may be electrically activated to dissect tissue. The forceps may also include a knife that is advanced between the jaw members to cut the treated tissue. As an alternative to a mechanical knife, an energy-based tissue cutting element may be provided to cut the treated tissue using energy, e.g., thermal, electrosurgical, ultrasonic, light, or other suitable energy. 
     SUMMARY 
     As used herein, the term “distal” refers to the portion that is being described which is further from a user, while the term “proximal” refers to the portion that is being described which is closer to a user. Further, to the extent consistent, any or all of the aspects detailed herein may be used in conjunction with any or all of the other aspects detailed herein. 
     Provided in accordance with aspects of the present disclosure is an end effector for a surgical instrument that includes a pair of opposing first and second jaw members each having a jaw housing supporting an electrically conductive tissue sealing plate disposed thereon. The electrically conductive tissue sealing plates of the first and second jaw members are disposed in opposition relative to one another. One or both of the first or second jaw members is movable relative to the other jaw member to grasp tissue therebetween. The electrically conductive tissue sealing plates of the first and second jaw members are adapted to connect to opposite potentials of an electrosurgical energy source. The electrically conductive tissue sealing plates of the first jaw member has an open T-shaped configuration defining a channel along a length thereof. A plasma blade is disposed within the channel of the electrically conductive tissue sealing plate of the first jaw member and extends to a distal end portion thereof. The plasma blade electrically connects to the energy source and is independently activatable from the electrically conductive tissue sealing plates. The plasma blade includes an insulative material on either side thereof configured to focus electrical and thermal energy to an exposed edge defined along a length of the plasma blade. 
     In aspects according to the present disclosure, the electrically conductive tissue sealing plate of the second jaw member has an open T-shaped configuration defining a channel along a length thereof and wherein an insulative member is disposed within the channel of the electrically conductive tissue sealing plate of the second jaw member in opposing vertical registration to the plasma blade. 
     In aspects according to the present disclosure, the insulative member is a made from a compliant high temperature silicone. In other aspects according to the present disclosure, the insulative member is selected from the group consisting of ceramic, parylene, nylon, and PTFE. 
     In aspects according to the present disclosure, a bridge is disposed within the first jaw member at a proximal end thereof, the bridge configured to provide electrical continuity across the electrically conductive tissue sealing plates of the first and second jaw members. 
     In aspects according to the present disclosure, a sensor is operably associated with one or both jaw members and is configured to sense when the jaw members are disposed in the open configuration, the sensor communicating with the electrical energy source to configure the electrosurgical instrument for monopolar use upon activation thereof. 
     In aspects according to the present disclosure, a bipolar activation switch is configured to provide electrical energy to both electrically conductive tissue sealing plates upon activation thereof and a monopolar activation switch configured to provide electrical energy to the plasma blade upon activation thereof. In other aspects according to the present disclosure, a bipolar activation switch is configured to provide electrical energy to both electrically conductive tissue sealing plates upon activation thereof and a monopolar activation switch configured to provide electrical energy to the plasma blade upon activation thereof, wherein the sensor disables power to the bipolar activation switch when the jaw members are disposed in the open configuration. 
     Provided in accordance with another aspects of the present disclosure is an end effector for a surgical instrument that includes a pair of opposing first and second jaw members each having a jaw housing supporting an electrically conductive tissue sealing plate disposed thereon. The electrically conductive tissue sealing plates of the first and second jaw members are disposed in opposition relative to one another, one or both of the first or second jaw member is movable relative to the other jaw member to grasp tissue therebetween. The electrically conductive tissue sealing plates of the first and second jaw members are adapted to connect to opposite potentials of an electrosurgical energy source. The electrically conductive tissue sealing plates of the first and second jaw member each have an open T-shaped configuration defining a channel along a length thereof. 
     A plasma blade is disposed within the channel of the electrically conductive tissue sealing plate of the first jaw member and extends to a distal end portion thereof. The plasma blade electrically connects to the energy source and is independently activatable from the electrically conductive tissue sealing plates. An insulative member is disposed within the channel of the electrically conductive tissue sealing plate of the second jaw member in opposing vertical registration to the plasma blade. 
     In aspects according to the present disclosure, the plasma blade includes an insulative material on either side thereof configured to focus electrical and thermal energy to an exposed edge defined along a length of the plasma blade. In other aspects according to the present disclosure, the insulative member is a made from a compliant high temperature silicone. In still other aspects according to the present disclosure, the insulative member is selected from the group consisting of ceramic, parylene, nylon, and PTFE. 
     In aspects according to the present disclosure, a bridge disposed within the first jaw member at a proximal end thereof, the bridge configured to provide electrical continuity across the electrically conductive tissue sealing plates of the first and second jaw members. 
     In aspects according to the present disclosure, a sensor is operably associated with one or both jaw members and is configured to sense when the jaw members are disposed in the open configuration, the sensor communicating with the electrical energy source to configure the electrosurgical instrument for monopolar use upon activation thereof. 
     In aspects according to the present disclosure, a bipolar activation switch is configured to provide electrical energy to both electrically conductive tissue sealing plates upon activation thereof and a monopolar activation switch configured to provide electrical energy to the plasma blade upon activation thereof. In other aspects according to the present disclosure, a bipolar activation switch is configured to provide electrical energy to both electrically conductive tissue sealing plates upon activation thereof and a monopolar activation switch configured to provide electrical energy to the plasma blade upon activation thereof, wherein the sensor disables power to the bipolar activation switch when the jaw members are disposed in the open configuration. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The above and other aspects and features of the present disclosure will become more apparent in view of the following detailed description when taken in conjunction with the accompanying drawings wherein like reference numerals identify similar or identical elements. 
         FIG.  1    is a perspective view of a shaft-based electrosurgical forceps provided in accordance with the present disclosure shown connected to an electrosurgical generator; 
         FIG.  2    is a perspective view of a hemostat-style electrosurgical forceps provided in accordance with the present disclosure; 
         FIG.  3    is a schematic illustration of a robotic surgical instrument provided in accordance with the present disclosure; 
         FIG.  4    is a perspective view of a distal end portion of the forceps of  FIG.  1   , wherein first and second jaw members of an end effector assembly of the forceps are disposed in a spaced-apart position, each jaw member including a respective electrically conductive tissue sealing plate disposed thereon; 
         FIG.  5 A  is a bottom, perspective view of the first jaw member of the end effector assembly of  FIG.  4   ; 
         FIG.  5 B  is a top, perspective view of the second jaw member of the end effector assembly of  FIG.  4   ; 
         FIG.  6    is an enlarged, front perspective cross section of respective distal ends the first and second jaw members of  FIG.  4    showing a plasma cutting element in accordance with the present disclosure; 
         FIG.  7    is schematic circuit diagram showing the various electrical connections of the first and second jaw members and the plasma cutting element to a generator for use with the forceps of  FIG.  4   ; 
         FIGS.  8 A and  8 B  show various views of a bridge associated with the end effector of the surgical instrument configured to provide continuity between electrically conductive tissue sealing plates; and 
         FIG.  9    shows an enlarged front cross section of the respective distal ends of an additional embodiment of the first and second jaw members of  FIG.  4    showing a plasma cutting element in accordance with additional aspects of the present disclosure; 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIG.  1   , a shaft-based electrosurgical forceps provided in accordance with the present disclosure is shown generally identified by reference numeral  10 . Aspects and features of forceps  10  not germane to the understanding of the present disclosure are omitted to avoid obscuring the aspects and features of the present disclosure in unnecessary detail. 
     Forceps  10  includes a housing  20 , a handle assembly  30 , a rotating assembly  70 , a first activation switch  80 , a second activation switch  90 , and an end effector assembly  100 . Forceps  10  further includes a shaft  12  having a distal end portion  14  configured to (directly or indirectly) engage end effector assembly  100  and a proximal end portion  16  that (directly or indirectly) engages housing  20 . Forceps  10  also includes cable “C” that connects forceps  10  to an energy source, e.g., an electrosurgical generator  500  ( FIGS.  1  and  7   ) Cable “C” includes wires  502 ,  504  ( FIG.  7   ) extending therethrough that have sufficient length to extend through shaft  12  in order to connect to one or both tissue-treating surfaces  114 ,  124  of j aw members  110 ,  120 , respectively, of end effector assembly  100  to provide energy thereto. First activation switch  80  is coupled to tissue-treating surfaces  114 ,  124  and the electrosurgical generator  500  for enabling the selective activation of the supply of energy to jaw members  110 ,  120  for treating, e.g., cauterizing, coagulating/desiccating, and/or sealing, tissue. As explained in more detail below, a second activation switch  90  is coupled to a plasma blade  130  of jaw member  120  and the electrosurgical generator  500  via wire  506  for enabling the selective activation of the supply of energy to plasma blade  130  for thermally cutting tissue. 
     As can be appreciated, after sealing, a vessel or tissue may be separated either by the use of a central cutting electrode that is elevated to a high temperature (e.g., a resistively heated element) or by using an electrosurgical electrode that is polarized opposite of the patient return pad (REM pad) during a so-called “cut” mode or cycle. The electrosurgical electrode used for cutting may either be a traditional uncoated electrode or, according to the present disclosure, employ a plasma blade  130 . 
     A plasma blade  130  is configured to direct a majority of the electrosurgical energy to an exposed cutting edge, e.g., cutting edge  130   b  ( FIG.  6   ). Many different configurations for the plasma blade  130  are discussed herein and generally include covering the lateral or side surfaces of the plasma blade  130  with an insulative material. As a result, energy supplied by the generator  500  is forced through a thin strip of material or edge  130   b  along periphery of the plasma blade  130  unlike an uncoated electrode. It is envisioned that better tissue separation reliability and efficiency may be achieved utilizing the plasma blade  130  as the plasma blade  130  directs energy through the exposed edge  130   b  on its way to the patient return pad (REM pad) or oppositely polarized sealing plate, e.g., sealing plate  113 , during the cut mode or cycle as opposed to the energy taking more favorable alternate paths available laterally that by-pass the tissue. Further, the plasma blade  130  allows the generator  500  to power the cut cycle or cut mode using much lower voltages adding to the overall efficiency of the design. 
     The cut cycle of a plasma blade  130  also differs from convention electrode cut modes or cut cycles as a result of the plasma blade&#39;s  130  particular configuration and the tendency to direct the electrical energy to and out from the cutting edge  130   b  requiring less energy to effectively cut the tissue. Typically, the energy waveform includes a maximum peak-to-peak voltage of up to about 1000V and a root mean squared voltage (VRms) of up to about 360V. The waveform is typically unpulsed but may be pulsed depending upon a particular purpose. 
     Handle assembly  30  of forceps  10  includes a fixed handle  50  and a movable handle  40 . Fixed handle  50  is integrally associated with housing  20  and handle  40  is movable relative to fixed handle  50 . Movable handle  40  of handle assembly  30  is operably coupled to a drive assembly (not shown) that, together, mechanically cooperate to impart movement of one or both of jaw members  110 ,  120  of end effector assembly  100  about a pivot  103  between a spaced-apart position and an approximated position to grasp tissue between tissue-treating surfaces  114 ,  124  of jaw members  110 ,  120 . As shown in  FIG.  1   , movable handle  40  is initially spaced-apart from fixed handle  50  and, correspondingly, jaw members  110 ,  120  of end effector assembly  100  are disposed in the spaced-apart position. Movable handle  40  is depressible from this initial position to a depressed position corresponding to the approximated position of jaw members  110 ,  120 . Rotating assembly  70  includes a rotation wheel  72  that is selectively rotatable in either direction to correspondingly rotate end effector assembly  100  relative to housing  20 . 
     Referring to  FIG.  2   , a hemostat-style electrosurgical forceps provided in accordance with the present disclosure is shown generally identified by reference numeral  210 . Aspects and features of forceps  210  not germane to the understanding of the present disclosure are omitted to avoid obscuring the aspects and features of the present disclosure in unnecessary detail. 
     Forceps  210  includes two elongated shaft members  212   a ,  212   b , each having a proximal end portion  216   a ,  216   b , and a distal end portion  214   a ,  214   b , respectively. Forceps  210  is configured for use with an end effector assembly  100 ′ similar to end effector assembly  100 . More specifically, end effector assembly  100 ′ includes first and second jaw members  110 ′,  120 ′ attached to respective distal end portions  214   a ,  214   b  of shaft members  212   a ,  212   b . Jaw members  110 ′,  120 ′ are pivotably connected about a pivot  103 ′. Each shaft member  212   a ,  212   b  includes a handle  217   a ,  217   b  disposed at the proximal end portion  216   a ,  216   b  thereof. Each handle  217   a ,  217   b  defines a finger hole  218   a ,  218   b  therethrough for receiving a finger of the user. As can be appreciated, finger holes  218   a ,  218   b  facilitate movement of the shaft members  212   a ,  212   b  relative to one another to, in turn, pivot jaw members  110 ′,  120 ′ from the spaced-apart position, wherein jaw members  110 ′,  120 ′ are disposed in spaced relation relative to one another, to the approximated position, wherein jaw members  110 ′,  120 ′ cooperate to grasp tissue therebetween. 
     One of the shaft members  212   a ,  212   b  of forceps  210 , e.g., shaft member  212   b , includes a proximal shaft connector  219  configured to connect forceps  210  to a source of energy, e.g., electrosurgical generator  500  ( FIGS.  1  and  7   ). Proximal shaft connector  219  secures a cable “C” to forceps  210  such that the user may selectively supply energy to jaw members  110 ′,  120 ′ for treating tissue. More specifically, a first activation switch  280  is provided for supplying energy to jaw members  110 ′,  120 ′ to treat tissue upon sufficient approximation of shaft members  212   a ,  212   b , e.g., upon activation of first activation switch  280  via shaft member  212   a . A second activation switch  290  disposed on either or both of shaft members  212   a ,  212   b  is coupled to the plasma blade (e.g., similar to plasma blade  130  of jaw member  120 ) operably associated with one of the jaw members  110 ′,  120 ′ of end effector assembly  100 ′ and to the electrosurgical generator  500  for enabling the selective activation of the supply of energy to the plasma blade  130  for thermally cutting tissue. 
     Jaw members  110 ′,  120 ′ define a curved configuration wherein each jaw member is similarly curved laterally off of a longitudinal axis of end effector assembly  100 ′. However, other suitable curved configurations including curvature towards one of the jaw members  110 ,  120 ′ (and thus away from the other), multiple curves with the same plane, and/or multiple curves within different planes are also contemplated. Jaw members  110 ,  120  of end effector assembly  100  ( FIG.  1   ) may likewise be curved according to any of the configurations noted above or in any other suitable manner. 
     Referring to  FIG.  3   , a robotic surgical instrument provided in accordance with the present disclosure is shown generally identified by reference numeral  2000 . Aspects and features of robotic surgical instrument  2000  not germane to the understanding of the present disclosure are omitted to avoid obscuring the aspects and features of the present disclosure in unnecessary detail. 
     Robotic surgical instrument  2000  includes a plurality of robot arms  2002 ,  2003 ; a control device  2004 ; and an operating console  2005  coupled with control device  2004 . Operating console  2005  may include a display device  2006 , which may be set up in particular to display three-dimensional images; and manual input devices  2007 ,  2008 , by means of which a surgeon may be able to telemanipulate robot arms  2002 ,  2003  in a first operating mode. Robotic surgical instrument  2000  may be configured for use on a patient  2013  lying on a patient table  2012  to be treated in a minimally invasive manner. Robotic surgical instrument  2000  may further include a database  21014 , in particular coupled to control device  2004 , in which are stored, for example, pre-operative data from patient  2013  and/or anatomical atlases. 
     Each of the robot arms  2002 ,  2003  may include a plurality of members, which are connected through joints, and an attaching device  2009 ,  2011 , to which may be attached, for example, an end effector assembly  2100 ,  2200 , respectively. End effector assembly  2100  is similar to end effector assembly  100 , although other suitable end effector assemblies for coupling to attaching device  2009  are also contemplated. End effector assembly  2200  may be any end effector assembly, e.g., an endoscopic camera, other surgical tool, etc. Robot arms  2002 ,  2003  and end effector assemblies  2100 ,  2200  may be driven by electric drives, e.g., motors, that are connected to control device  2004 . Control device  2004  (e.g., a computer) may be configured to activate the motors, in particular by means of a computer program, in such a way that robot arms  2002 ,  2003 , their attaching devices  2009 ,  2011 , and end effector assemblies  2100 ,  2200  execute a desired movement and/or function according to a corresponding input from manual input devices  2007 ,  2008 , respectively. Control device  2004  may also be configured in such a way that it regulates the movement of robot arms  2002 ,  2003  and/or of the motors. 
     Turning to  FIG.  4   , one embodiment of a known end effector assembly  100 , as noted above, includes first and second jaw members  110 ,  120 . Each jaw member  110 ,  120  may include a structural frame  111 ,  121 , a jaw housing  112 ,  122 , and a tissue-treating plate  113 ,  123  defining the respective tissue-treating surface  114 ,  124  thereof. Alternatively, only one of the j aw members, e.g., jaw member  120 , may include the structural frame  121 , jaw housing  122 , and tissue-treating plate  123  defining the tissue-treating surface  124 . In such embodiments, the other jaw member, e.g., jaw member  110 , may be formed as a single unitary body, e.g., a piece of conductive material acting as the structural frame  111  and jaw housing  112  and defining the tissue-treating surface  114 . An outer surface of the jaw housing  112 , in such embodiments, may be at least partially coated with an insulative material or may remain exposed. For the purposes herein, the term “insulative” is defined as thermal or electrical conductivity that is lower than the adjacent materials of the jaw members  110 ,  120 . Materials or coatings described herein may be thermally insulative, electrically insulative or both. 
     In embodiments, tissue-treating plates  113 ,  123  may be deposited onto jaw housings  112 ,  122  or jaw inserts (not shown) disposed within jaw housings  112 ,  122 , e.g., via sputtering. Alternatively, tissue-treating plates  113 ,  123  may be pre-formed and engaged with jaw housings  112 ,  122  and/or jaw inserts (not shown) disposed within jaw housings  112 ,  122  via, for example, overmolding, adhesion, mechanical engagement, etc. 
     Referring in particular to  FIGS.  4 - 5 B , jaw member  110 , as noted above, may be configured similarly as jaw member  120 , may be formed as a single unitary body, or may be formed in any other suitable manner so as to define a structural frame  111  and a tissue-treating surface  114  opposing tissue-treating surface  124  of jaw member  120 . Structural frame  111  includes a proximal flange portion  116  about which jaw member  110  is pivotably coupled to jaw member  120 . In shaft-based or robotic embodiments, proximal flange portion  116  may further include an aperture  117   a  for receipt of pivot  103  and at least one protrusion  117   b  extending therefrom that is configured for receipt within an aperture defined within a drive sleeve of the drive assembly (not shown) such that translation of the drive sleeve, e.g., in response to actuation of movable handle  40  ( FIG.  1   ) or a robotic drive, pivots jaw member  110  about pivot  103  and relative to jaw member  120  between the spaced-apart position and the approximated position. However, other suitable drive arrangements are also contemplated, e.g., using cam pins and cam slots, a screw-drive mechanism, etc. 
     Regardless of the particular configuration of jaw member  110 , jaw member  110  may include a longitudinally-extending insulative member  115  extending along at least a portion of the length of tissue-treating surface  114 . Insulative member  115  may be transversely centered on tissue-treating surface  114  or may be offset relative thereto. Further, insulative member  115  may be disposed, e.g., deposited, coated, etc., on tissue-treating surface  114 , may be positioned within a channel or recess defined within tissue-treating surface  114 , or may define any other suitable configuration. Additionally, insulative member  115  may be substantially (within manufacturing, material, and/or use tolerances) coplanar with tissue-treating surface  114 , may protrude from tissue-treating surface  114 , may be recessed relative to tissue-treating surface  114 , or may include different portions that are coplanar, protruding, and/or recessed relative to tissue-treating surface  114 . Insulative member  115  may be formed from, for example, compliant high temperature silicone, ceramic, parylene, nylon, PTFE, or other suitable material(s) (including combinations of insulative and non-insulative materials). The insulative member  115  may also be formed from polybenzimidazole or similar materials. 
     With reference to  FIGS.  4  and  5 B , as noted above, jaw member  120  includes a structural frame  121 , a jaw housing  122 , and a tissue-treating plate  123  defining the tissue-treating surface  124  thereof. Jaw member  120  further includes a plasma blade  130 . Structural frame  121  defines a proximal flange portion  126  and a distal body portion (not shown) extending distally from proximal flange portion  126 . Proximal flange portion  126  is bifurcated to define a pair of spaced-apart proximal flange portion segments that receive proximal flange  111  of jaw member  110  therebetween and define aligned apertures  127  configured for receipt of pivot  103  therethrough to pivotably couple jaw members  110 ,  120  with one another ( FIG.  4   ). 
     Jaw housing  122  of jaw member  120  is disposed about the distal body portion of structural frame  121 , e.g., via overmolding, adhesion, mechanical engagement, etc., and supports tissue-treating plate  123  thereon, e.g., via overmolding, adhesion, mechanical engagement, depositing (such as, for example, via sputtering), etc. 
     As shown in  FIG.  6   , tissue sealing plate  123  is generally open T-shaped to define a longitudinally-extending slot  125  therealong for housing the plasma blade  130  therein. Tissue-treating plate  123 , as noted above, defines tissue-treating surface  124 . Longitudinally-extending slot  125  is defined through tissue-treating plate  123  and is positioned to oppose insulative member  115  of jaw member  110  ( FIG.  5 A ) in the approximated position. Slot  125  may extend through a portion of jaw housing  122 , a jaw insert (if so provided), and/or other components of j aw member  120  to enable receipt of the plasma blade  130  at least partially within slot  125 . 
     Plasma blade  130  is partially covered on either side with an insulative material  128   a ,  128   b  along a length thereof to direct the energy (electrical and thermal) to exposed surfaces, e.g., a top surface  130   b  of the plasma blade  130 . In embodiments, insulative material  128   a ,  128   b  (glass, ceramic, etc.) covers the entire surface of the plasma blade  130  except the exposed top surface or cutting edge  130   b . Plasma blade  130  may be configured to contact insulative member  115  ( FIG.  5 A ) in the approximated position and may be configured to regulate (or contribute to the regulation of) a gap distance between tissue-treating surfaces  114 ,  124  in the approximated position. Alternatively or additionally, one or more stop members (not shown) associated with jaw member  110  and/or jaw member  120  may be provided to regulate the gap distance between tissue-treating surfaces  114 ,  124  in the approximated position. 
     As mentioned above, plasma blade  130  is surrounded by an insulative material  128   a ,  128   b  disposed within slot  125  or attached to the plasma blade  130  to both electrically the isolate plasma blade  130  from tissue-treating plate  123  and to direct energy to the exposed edge or top surface  130   b  for cutting tissue. Plasma blade  130  and insulative material  128   a ,  128   b  may similarly or differently be substantially (within manufacturing, material, and/or use tolerances) coplanar with tissue-treating surface  124 , may protrude from tissue-treating surface  124 , may be recessed relative to tissue-treating surface  124 , or may include different portions that are coplanar, protruding, and/or recessed relative to tissue-treating surface  124 . The insulative materials  128   a ,  128   b  may be directed deposited onto the plasma blade  130 , may be taped onto the plasma blade  130 , may be configured to encapsulated or cover the plasma blade  130 , may form a pocket for receiving the plasma blade  130 , may be molded to the plasma blade  130  or in any other fashion known in the art. 
     As can be appreciated, configuring seal plate  123  in an open T-shape simplifies electrical connections as only a single point of electrical connection is required with the integral, yet un-bisected design. The open T-shaped configuration allows the plasma blade  130  to extend beyond the distal end of the jaw member  120  for dissection purposes, if desired. A bridge  122   b  may be disposed at the proximal end of the jaw member  120  to provide electrical continuity across the seal plate  123  and simplify manufacturing, electrical connection and assembly. The bridge  122   b  allows the seal plate  123  to remain split along the entire length of the jaw member  120  ( FIGS.  8 A and  8 B ) and retain electrical continuity across the same. 
     Jaw member  110  also includes seal plate  113  affixed thereto in opposing relation to jaw member  120 . Similarly, seal plate  113  is generally open T-shaped along a length thereof and includes a channel  117  defined therealong that is configured to house insulative member  115  therein. Insulative member  115  is disposed in vertical registration with plasma blade  130 . 
       FIG.  7    illustrates the various electrical connections to the sealing plate  113 ,  123  and the plasma blade  130  to the generator  500  to allow both bipolar sealing and monopolar dissection. More particularly, seal plates  113 ,  123  are electrically connected to the generator via cable “C” ( FIG.  1   ) that houses wires,  504 ,  502 , respectively. As mentioned above, the open T-shaped configuration of both plates  113 ,  123  simplifies assembly requiring only one electrical connection to each plate. Plasma blade  130  is also connected to the generator  500  via wire  506  disposed within cable “C”. A return electrode monitoring (REM) connection  600  (e.g., return pad, plate, etc.) may be connected to the patient or proximate the tissue site to provide and alternative return path for electrical energy during monopolar activation. Alternatively, seal plate  113  may be configured to act as an electrical return. 
     During bipolar sealing, the generator  500  provides electrical energy to seal plates  113 ,  123  to seal tissue “T” disposed therebetween according to one or more known sealing algorithms. As a result thereof, during activation, a tissue seal “S” is created between sealing plates  113 ,  123  on either side of channels  117  and  125  respectively. Once sealed, the algorithm may be configured to automatically activate the plasma blade  130  to transect the tissue “T” substantially along the center of the opposing seal plates  113 ,  123 . As mentioned above, the upper surface or edge  130   b  of the plasmas blade  130  is the only portion thereof that is exposed thereby eliminating any arc effect (to other conductors) and focusing the electrical and thermal energy along a defined cutting path. During activation of the plasma blade  130  and one or more of the sealing plates  113 ,  123  may remain electrically energized, e.g., sealing plate  113 , to act as an electrical return to generator  500 . Alternatively, a return pad  600  (e.g., REM system) may be electrically energized and act as the electrical return for the plasma blade  130 . 
     As mentioned above, the plasma blade  130  may be utilized for monopolar dissection, e.g., open jaw dissection. More particularly, with the jaw members  110 ,  120  disposed in an open configuration, the plasma blade  130  may be activated via switch  90  with a first electrical potential which is directed through the tissue and to a return pad  600  (e.g., REM system) having a second electrical potential. Tissue may be dissected as jaw member  120  is moved into contact therewith. 
       FIGS.  8 A and  8 B  show the open T-shaped configuration of seal plate  123  wherein, unlike conventional seal plates, the plasma blade  130  extends to the distal tip  122   a  of the jaw member  120  between the open-ended seal plate  123 . The plasma blade  130  may also be configured to extend to a point proximate the distal tip  122   a  or beyond the distal tip  122   a . The bridge  122   b  which may be buried in the housing  122  connects across the proximal end of the seal plate  123  to retain electrical continuity. 
     Generally referring to  FIGS.  1 - 5 B , tissue-treating plates  113 ,  123  are formed from an electrically conductive material, e.g., for conducting electrical energy therebetween for treating tissue, although tissue-treating plates  113 ,  123  may alternatively be configured to conduct any suitable energy, e.g., thermal, microwave, light, ultrasonic, etc., through tissue grasped therebetween for energy-based tissue treatment. As mentioned above, tissue-treating plates  113 ,  123  are coupled to activation switch  80  and electrosurgical generator “G” ( FIG.  1   ) such that energy may be selectively supplied to tissue-treating plates  113 ,  123  and conducted therebetween and through tissue disposed between jaw members  110 ,  120  to treat tissue, e.g., seal tissue on either side and extending across plasma blade  130 . 
     Plasma blade  130 , on the other hand, is configured to connect to electrosurgical generator  500  ( FIG.  1   ) and second activation switch  90  to enable selective activation of the supply of energy to plasma blade  130  for heating the tip  130   b  of plasma blade  130  to thermally cut tissue disposed between jaw members  110 ,  120 , e.g., to cut the sealed tissue into first and second sealed tissue portions. Insulative materials  128   a ,  128   b  are disposed on either side of the plasma blade  130  to focus the thermal energy to the tip  130   b . The plasma blade  130  may be controlled by the surgeon, may be automatically controlled by one or more parameters or inputs or feedback associated with the generator  500  or by an algorithm. One or multiple switches  80 ,  90  may be utilized to accomplish this purpose. For example, if a single switch is utilized, the generator  500  may stop activation of the tissue-treating plates  113 ,  123  once the seal cycle is complete and automatically initiate activation of the plasma blade  130 . Sealing and transection of tissue may be simultaneous or sequential depending upon the particular algorithm being utilized. Other configurations including multi-mode switches, other separate switches, etc. may alternatively be provided. Cross reference is made to U.S. Provisional Patent Application Ser. No. 62/952,232 the entire contents of which being incorporated by reference herein. 
     A sensor  700  ( FIGS.  1  and  2   ) may be disposed within the housing  20 , handle  50  or generator  500  that senses when the jaw members  110 ,  120  are disposed in the open configuration and automatically configures the forceps  10  (or forceps  210 ) for open monopolar dissection. The sensor  700  may be designed to automatically configure the sealing plates  113 ,  123 , plasma blade  130  and possible a return pad  600  for monopolar use upon sensing the jaw members  110 ,  120  are disposed in an open configuration. Moreover, the sensor  700  may cut power to the bipolar switch  80  and allow only switch  90  to be operable upon sensing the jaw members  110 ,  120  are disposed in an open configuration or, with a single switch system, automatically configure the instrument  10 ,  210  for bipolar sealing or monopolar dissection depending on the position of the jaw members  110 ,  120 . 
       FIG.  9    shows an end effector  1000  that is generally similar to end effector  100  and as such will only be described in sufficient detail to note the differences therebetween. End effector assembly  1000  includes first and second jaw members  1110 ,  1120  each including respective jaw housings  112 ,  122  and tissue-treating plates  1113 ,  1123  defining the respective tissue-treating surface  1114 ,  1124  thereof. 
     Tissue sealing plate  1123  is generally open T-shaped to define a longitudinally-extending slot  1125  therealong for housing the plasma blade  1130  therein. Longitudinally-extending slot  1125  is defined through tissue-treating plate  1123  and is positioned to oppose insulative member  1115  of jaw member  1110  in the approximated position. Slot  1125  may extend through a portion of jaw housing  1122  and/or other components of jaw member  1120  to enable receipt of the plasma blade  1130  at least partially within slot  1125 . 
     Plasma blade  1130  is partially covered on either side with an insulative material  1128  along a length thereof to direct the energy (electrical and thermal) to exposed surfaces, e.g., a top surface  1130   b  of the plasma blade  1130 . In embodiments or methods, the plasma blade  1130  may be encapsulated in glass via a so-called dip and cure method or alternatively the glass may be screen printed thereon. In other embodiments or methods, a ceramic may be sprayed onto the sides of the plasma blade  1130  leaving the edge  1130   b  exposed. The ceramic may be deposited onto the plasma blade  1130  via electrolytic oxidation. 
     In yet other embodiments or methods, a polyamide such as the polyamide sold under the trademark Kapton® may be taped or film coated onto the sides of the plasma blade  1130  leaving edge  1130   b  exposed. In other embodiments or methods, molded engineering plastics may be disposed on either side of the plasma blade  1130 , e.g., plastics such as polyphthalamide (PPA) such as that sold under the trademark Amodel®, polyetheretherketone (PEEK), polybenzimidazole (PBI), etc. A synthetic fluoropolymer such as polytetrafluoroethylene (PTFE) may also be disposed on either side of the plasma blade  1130 . In still other embodiments, silicone may be molded on either side of the plasma blade  1130 . In some of the above applications or methods, post grinding may be necessary reveal the exposed edge  1130   b . In other instances, one or more techniques may be utilized to automatically expose the edge  1130   b  during the process of insulating the sides of the plasma blade  1130 . 
     Plasma blade  1130  may be configured to contact insulative member  1115  in the approximated position and may be configured to regulate (or contribute to the regulation of) a gap distance between tissue-treating surfaces  1114 ,  1124  in the approximated position. In addition to using a return pad or REM pad (not shown), the insulative member  1115  may be configured to direct electrical energy away from the sealed tissue. For example, a return electrode  1175  may be embedded into the insulative member  1115  and connected to the electrical return. As such, the embedded electrode  1175  directs electrical energy from the plasma blade  1130  away from the seal plates and tissue. Other configurations and methods of directing electrical energy may also be employed, e.g., utilizing a monolithic opposing jaw, e.g., jaw member  1110 , to act as the electrical return or the opposing seal plate, e.g., seal plate  1113 . 
     In other aspects according to the present disclosure, a coating  1177  may be applied to the inner peripheral edges of the seal plates  1113 ,  1123  to impede electrical energy towards the tissue. For example, a high temperature silicone such as SiO2 may be employed for this purpose. 
     Referring back to  FIGS.  1 - 6    and as mentioned above, plasma blade  130  is surrounded by an insulative material  128   a ,  128   b  disposed within slot  125  or attached to the plasma blade  130  to both electrically the isolate plasma blade  130  from tissue-treating plate  123  and to direct energy to the exposed edge or top surface  130   b  for cutting tissue. Plasma blade  130  and insulative material  128   a ,  128   b  may similarly or differently be substantially (within manufacturing, material, and/or use tolerances) coplanar with tissue-treating surface  124 , may protrude from tissue-treating surface  124 , may be recessed relative to tissue-treating surface  124 , or may include different portions that are coplanar, protruding, and/or recessed relative to tissue-treating surface  124 . The insulative materials  128   a ,  128   b  may be directed deposited onto the plasma blade  130 , may be taped onto the plasma blade  130 , may be configured to encapsulated or cover the plasma blade  130 , may form a pocket for receiving the plasma blade  130 , may be molded to the plasma blade  130  or in any other fashion known in the art. 
     While several embodiments of the disclosure have been shown in the drawings, it is not intended that the disclosure be limited thereto, as it is intended that the disclosure be as broad in scope as the art will allow and that the specification be read likewise. For example, the plasma blade  130  may be segmented along the length of the jaw members  110 ,  120  and independently activatable depending upon a particular purpose. Therefore, the above description should not be construed as limiting, but merely as exemplifications of particular embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto.