Vessel sealing instrument with cutting mechanism

An end effector assembly for use with an instrument for sealing and cutting tissue includes a pair of opposing first and second jaw members movable relative to the to grasp tissue therebetween. Each jaw member including a jaw housing and an electrically conductive surface adapted to connect to a source of electrosurgical energy such that the electrically conductive surfaces are capable of conducting electrosurgical energy through tissue held therebetween to effect a tissue seal. One of the electrically conductive surfaces including a channel defined therein and extending along a length thereof that communicates with a nozzle disposed in the jaw housing. The nozzle is configured to direct high pressure fluid from a fluid source into the channel for cutting tissue grasped between the jaw members.

BACKGROUND

The present disclosure relates to a forceps used for both endoscopic and open surgical procedures that includes a variety of electrode assemblies configured to allows a user to selectively treat and/or cut tissue. More particularly, the present disclosure relates to a forceps that includes a pair of opposing jaw members configured to grasp tissue and allow a user to selectively treat tissue utilizing electrosurgical energy and/or allow a user cut tissue utilizing one or more mechanical or electro-mechanical cutting mechanisms.

TECHNICAL FIELD

Open or endoscopic electrosurgical forceps utilize both mechanical clamping action and electrical energy to effect hemostasis. The electrode of each opposing jaw member is charged to a different electric potential such that when the jaw members grasp tissue, electrical energy can be selectively transferred through the tissue. A surgeon can either cauterize, coagulate/desiccate and/or simply reduce or slow bleeding, by controlling the intensity, frequency and duration of the electrosurgical energy applied between the electrodes and through the tissue. In order to effectively seal vessels or tissue, two predominant mechanical parameters must be accurately controlled: the pressure applied to the tissue; and the gap distance between the electrodes.

Vessel or tissue sealing is more than “cauterization” which involves the use of heat to destroy tissue (also called “diathermy” or “electrodiathermy”). Vessel sealing is also more than “coagulation” which is the process of desiccating tissue wherein the tissue cells are ruptured and dried, “Vessel sealing” is defined as the process of liquefying the collagen, elastin and ground substances in the tissue so that the tissue reforms into a fused mass with significantly-reduced demarcation between the opposing tissue structures.

Typically and particularly with respect to endoscopic electrosurgical procedures, once a vessel is sealed, the surgeon has to remove the sealing instrument from the operative site, substitute a new instrument through the cannula and accurately sever the vessel along the newly formed tissue seal. As can be appreciated, this additional step may be both time consuming (particularly when sealing a significant number of vessels) and may contribute to imprecise separation of the tissue along the sealing line due to the misalignment or misplacement of the severing instrument along the center of the tissue seal.

SUMMARY

The present disclosure relates to an end effector assembly for use with an instrument for sealing and cutting tissue and includes a pair of opposing first and second jaw members movable relative to the other from a first position wherein the jaw members are disposed in spaced relation relative to one another to a second position wherein the jaw members cooperate to grasp tissue therebetween. Each jaw member includes a jaw housing and an electrically conductive surface adapted to connect to a source of electrosurgical energy such that the electrically conductive surfaces are capable of conducting electrosurgical energy through tissue held therebetween to effect a tissue seal. One (or both) of the electrically conductive surfaces includes a channel defined therein that extends along a length thereof that communicates with a nozzle disposed in the jaw housing. The nozzle is configured to direct high pressure fluid from a fluid source into the channel for cutting tissue grasped between the jaw members.

In one embodiment, the nozzle communicates with one or more fluid conduits disposed within the jaw housing that are configured to convey high pressure fluid from a fluid source. One or more valves may be included that are configured to regulate the flow of high pressure fluid from the fluid source.

In another embodiment, each electrically conductive surface includes a channel defined therein that extends along a length thereof that communicates with a corresponding nozzle disposed within each respective jaw housing. The nozzle(s) may be tapered either longitudinally or transversally depending upon a particular purpose.

The present disclosure also relates to an end effector assembly for use with an instrument for sealing and cutting tissue and includes a pair of opposing first and second jaw members movable relative to the other from a first position wherein the jaw members are disposed in spaced relation relative to one another to a second position wherein the jaw members cooperate to grasp tissue therebetween. Each jaw member includes a jaw housing and an electrically conductive surface adapted to connect to a source of electrosurgical energy such that the electrically conductive surfaces are capable of conducting electrosurgical energy through tissue held therebetween to effect a tissue seal. An adhesive strip is disposed along a length of one (or both) of the electrically conductive surfaces. After electrical activation of the electrically conductive surfaces to effect a tissue seal, the adhesive strip is configured to retain a portion of the tissue seal to essentially tear the portion of the tissue seal away from remaining tissue when the tissue is removed from between the jaw members. The adhesive strip may be configured to include a heat-activated adhesive.

In one embodiment, the adhesive strip includes a plurality of nozzles disposed in the jaw housing operatively coupled to an adhesive fluid supply. The plurality of nozzles may be configured to communicate with one or more fluid conduits disposed within the jaw housing that convey the adhesive fluid from an adhesive fluid supply. One or more valves may be included that are configured to regulate the flow of adhesive fluid from the adhesive fluid supply. One or more of the plurality of nozzles may be tapered to direct the flow of the adhesive fluid onto the adhesive strip in a uniform and consistent manner to facilitate separation of tissue. The adhesive fluid supply may include a heat-activated adhesive fluid.

The present disclosure also relates to an end effector assembly for use with an instrument for sealing and cutting tissue and includes a pair of opposing first and second jaw members movable relative to the other from a first position wherein the jaw members are disposed in spaced relation relative to one another to a second position wherein the jaw members cooperate to grasp tissue therebetween. Each jaw member includes a jaw housing and an electrically conductive surface adapted to connect to a source of electrosurgical energy such that the electrically conductive surfaces are capable of conducting electrosurgical energy through tissue held therebetween to effect a tissue seal. A cutting mechanism with a sharpened leading edge is fixed between the jaw members near a proximal end thereof. The sharpened leading edge of the cutting mechanism is positioned to cut tissue between the jaw members upon forward movement of the jaw members along the tissue seal. A stop member may be disposed at the distal end of one of the jaw members that is dimensioned to maintain a gap distance between the jaw members during electrical activation of the electrically conductive surfaces.

In one embodiment, the stop member is operatively affixed to a guide rail-system disposed within one of the jaw housings that allows the jaw members and the cutting mechanism to move forward over the stop member to sever tissue along the tissue seal.

The present disclosure also relates to an end effector assembly for use with an instrument for sealing and cutting tissue and includes a pair of opposing first and second jaw members movable relative to the other from a first position wherein the jaw members are disposed in spaced relation relative to one another to a second position wherein the jaw members cooperate to grasp tissue therebetween. Each jaw member includes a jaw housing and an electrically conductive surface adapted to connect to a source of electrosurgical energy such that the electrically conductive surfaces are capable of conducting electrosurgical energy through tissue held therebetween to effect a tissue seal. One or both of the jaw members includes an elongated perforation strip that extends inwardly from the electrically conductive surface thereof. The elongated perforation strip is dimensioned to perforate the tissue upon closure of the jaw members against tissue and activation of the electrically conductive surfaces to effect a tissue seal. The perforation strips on each respective jaw member may be configured to intermesh with one another upon closure of the jaw members against tissue and activation of the electrically conductive surfaces to effect a tissue seal.

DETAILED DESCRIPTION

Referring initially toFIGS. 1A-1C, a bipolar forceps for use in connection with endoscopic surgical procedures is depicted. For the purposes herein, either an endoscopic instrument or an open instrument may be utilized with the various electrode assemblies described herein. Obviously, different electrical and mechanical connections and considerations apply to each particular type of instrument, however, the novel aspects with respect to the electrode assembly and the operating characteristics associated therewith remain generally consistent with respect to both the open or endoscopic designs.

Generally, the end effector designs depicted herein are used to cut tissue along a vessel seal. However, any one of the various designs may be utilized to cut tissue after electrically treating tissue in a different fashion (e.g., coagulating or cauterizing tissue) or for simply cutting tissue without necessarily electrically treating tissue.

Bipolar forceps10generally includes a housing20, a handle assembly30, a rotating assembly80, a switch assembly70and an electrode assembly105having opposing jaw members110and120that mutually cooperate to grasp, seal and divide tubular vessels and vascular tissue. More particularly, forceps10includes a shaft12that has a distal end16dimensioned to mechanically engage the electrode assembly100and a proximal end14that mechanically engages the housing20. The shaft12may include one or more known mechanically engaging components that are designed to securely receive and engage the electrode assembly100such that the jaw members110and120are pivotable relative to one another to engage and grasp tissue therebetween.

The proximal end14of shaft12mechanically engages the rotating assembly80to facilitate rotation of the electrode assembly100. In the drawings and in the descriptions which follow, the term “proximal”, as is traditional, will refer to the end of the forceps10which is closer to the user, while the term “distal” will refer to the end which is further from the user. Details relating to the mechanically cooperating components of the shaft12and the rotating assembly80are described in commonly-owned U.S. patent application Ser. No. 11/827,297 entitled “VESSEL SEALER AND DIVIDER”.

Handle assembly30includes a fixed handle50and a movable handle40. Fixed handle50is integrally associated with housing20and handle40is movable relative to fixed handle50to actuate the opposing jaw members110and120of the electrode assembly100as explained in more detail below.

As mentioned above, electrode assembly100is attached to the distal end16of shaft12and includes the opposing jaw members110and120. Movable handle40of handle assembly30imparts movement of the jaw members110and120about a pivot160from an open position wherein the jaw members110and120are disposed in spaced relation relative to one another, to a clamping or closed position wherein the jaw members110and120cooperate to grasp tissue therebetween.

Referring now toFIGS. 1B and 1C, enlarged views of an end effector assembly100of a prior device are shown in an open position for approximating tissue. Jaw members110and120are generally symmetrical and include similar component features which cooperate to permit facile rotation about pivot pin160to effect the sealing and dividing of tissue. As a result and unless otherwise noted, only jaw member110and the operative features associated therewith are describe in detail herein but as can be appreciated, many of these features apply to jaw member120as well.

Jaw member110also includes a jaw housing116, an insulative substrate or insulator114and an electrically conducive surface112. Insulator114is configured to securely engage the electrically conductive sealing surface112. This may be accomplished by stamping, by overmolding, by overmolding a stamped electrically conductive sealing plate and/or by overmolding a metal injection molded seal plate. All of these manufacturing techniques produce an electrode having an electrically conductive surface112that is substantially surrounded by an insulating substrate114.

As mentioned above, jaw member120includes similar elements which include: a jaw housing126; insulator124; and an electrically conducive sealing surface122that is dimensioned to securely engage the insulator124. Electrically conductive surface122and the insulator124, when assembled, form a longitudinally-oriented channel168defined therethrough for reciprocation of the knife blade205. Knife channel168facilitates longitudinal reciprocation of the knife blade205along a preferred cutting plane to effectively and accurately separate the tissue along the formed tissue seal. Although not shown, jaw member110may also include a knife channel that cooperates with knife channel168to facilitate translation of the knife through tissue.

Jaw members110and120are electrically isolated from one another such that electrosurgical energy can be effectively transferred through the tissue to form a tissue seal. Electrically conductive sealing surfaces112and122are also insolated from the remaining operative components of the end effector assembly100and shaft12. A plurality of stop members150may be employed to regulate the gap distance between the sealing surfaces112and122to insure accurate, consistent and reliable tissue seals.

FIGS. 2-7show various embodiments of different jaw member configurations for selectively cutting tissue disposed between opposing jaw members. Although is some instances only one jaw member, e.g., jaw member220,320and420is shown for the various envisioned embodiments, it should be understood that a complementary jaw member having similar operating components may be utilized for sealing purposes or to facilitate the cutting process.

FIG. 2shows one embodiment of a jaw member220for use with the forceps10described above. Jaw member220includes an insulative housing224having an electrically conductive surface222disposed thereon configured for conducting energy to tissue. A longitudinally-oriented channel225is defined within the electrically conductive surface222and extends from a proximal end of the conductive surface222to a distal end thereof. Channel225is configured to fluidly communicate with a nozzle227disposed in housing224, which is, in turn, operatively coupled to a high pressure fluid supply250via conduit235disposed through jaw member220. Nozzle227is configured to redirect the flow of fluid228from the high pressure fluid supply250and conduit235into the channel225. Nozzle227may be geometrically configured, e.g., longitudinally and/or transversally tapered, to increase the fluid pressure and/or mold or shape the fluid228exiting the nozzle227and channel225into a knife-like stream for cutting tissue disposed between the jaw members.

Jaw member220cooperates with an opposing jaw member (not shown) to approximate and seal tissue disposed therebetween. The opposing jaw member may be configured in a similar manner to direct a knife-like stream of fluid228into tissue to cut the tissue from an opposing direction to facilitate the cutting process. Configuring both jaw members in this manner may facilitate the cutting process and enhance the overall cutting effect. The opposing fluid channel (not shown) may be connected to the same or an independent fluid source (via a second conduit (not shown)) depending upon a particular purpose.

In use, the user initially energizes the opposing electrically conductive surface222and, for example, sealing plate112ofFIG. 1, to effectively seal tissue disposed between the jaw members as described above. Once the tissue is sealed or otherwise treated, a visual or audible warning is typically displayed or otherwise transmitted to the user to indicate completion of the treatment process. If desired, the user then initiates the cutting process to separate the tissue along the tissue seal (or treatment area) by opening one or more valves255to induce the high pressure fluid228through the conduit235to the nozzle227. The high pressure fluid228is directed into tissue225to effectively sever the tissue along the longitudinally-oriented channel in the sealing surface222.

As mentioned above, the opposing jaw member (not shown) may include a similar configuration to enhance the cutting effect by directing high pressure fluid228into tissue from the opposite direction. Alternatively, the tissue may be cut without initially sealing or otherwise treating tissue.

FIG. 3Ashows another embodiment of a jaw member320for use with the forceps10described above. Jaw member320includes an insulative housing324having an electrically conductive surface322disposed thereon configured for conducting energy to tissue. Similar to the embodiment of the jaw member described inFIG. 2above, jaw member320cooperates with an opposing jaw member (not shown) to approximate and seal tissue disposed therebetween. The opposing jaw member may be configured in a similar manner to tear tissue from an opposing direction to facilitate the cutting process.

Jaw member320is configured to include a longitudinally-oriented strip of adhesive325disposed along sealing surface322. Adhesive strip325is configured to both facilitate retention of tissue during the initial treatment of tissue (e.g., tissue sealing) and effectively grip the tissue along the center of the tissue seal to induce the tissue to tear therealong when the jaw members320(opposing jaw member not shown) are removed. The adhesive strip325may be a heat-activated adhesive or a heat-enhanced adhesive to facilitate the tearing, i.e., cutting, process.

FIG. 3Bshows a similar embodiment of a jaw member420for use with the forceps10which also utilizes an adhesive428to effectively tear tissue along a tissue seal. Jaw member420includes an insulative housing424having an electrically conductive surface422disposed thereon configured for conducting energy to tissue. Similar to the embodiments above, jaw member420cooperates with an opposing jaw member (not shown) to approximate and seal tissue disposed therebetween. The opposing jaw member may be configured in a similar manner to tear tissue from an opposing direction to facilitate the cutting process.

A longitudinally-oriented strip425is defined within the electrically conductive surface422and extends from a proximal end of the conductive surface422to a distal end thereof. Strip425is configured to include a plurality of nozzles426disposed in housing424, which are, in turn, operatively coupled to a fluid adhesive supply450via conduit435disposed through jaw member420. Nozzles426are configured to direct the flow of adhesive fluid428from the supply450and conduit435onto strip425through corresponding nozzle ports427arranged longitudinally along strip425. Nozzle ports427may be geometrically configured, e.g., longitudinally and/or transversally tapered, to direct the flow of the adhesive428fluid onto the strip in a uniform and consistent manner to facilitate separation of tissue.

Adhesive428is configured to both facilitate retention of tissue during the initial treatment of tissue (e.g., tissue sealing) and effectively grip the tissue along the center of the tissue seal to induce the tissue to tear therealong when the jaw members420(opposing jaw member not shown) are removed. The adhesive428may be a heat-activated adhesive or a heat-enhanced adhesive to facilitate the tearing, i.e., cutting, process. Moreover, the adhesive may be simultaneously or sequentially administered during or after the creation of a tissue seal. For example, the surgeon may initially energize the jaw members to seal tissue disposed therebetween and then open a valve to administer the adhesive428along the strip425. The adhesive428then cures and grips the tissue to promote separation thereof when the jaw members are removed. The conduit435may also be fluidly connected to a cleaning fluid supply (not shown) which dissolves the adhesive428on the strip425between uses such that the remaining tissue may be washed away after separation from the tissue seal.

FIG. 4Ashows yet another embodiment of a cutting mechanism for forceps10and includes end effector assembly500having opposing jaw members510and520that are moveable relative to one another to engage tissue therebetween to effect a tissue seal. Jaw members510and520include respective jaw housings516and524that support electrically conductive surface512and522, respectively. Each electrically conductive surface512and522is adapted to connect to an electrical energy source such that the electrically conductive surfaces512and522may conduct energy to tissue disposed therebetween to effectively treat, e.g., seal, tissue upon activation of the electrosurgical generator (not shown).

A cutting mechanism540is fixed between the jaw members510and520near a proximal end thereof. The cutting mechanism540includes a sharpened edge545at a distal end thereof. Once the tissue is treated, e.g., sealed, the surgeon relaxes the closing pressure of the jaw members510and520against the tissue (e.g., by relaxing the jaw handle40(SeeFIG. 1)) and simply moves the jaw members510and520forward such that the sharpened edge545of the knife540severs tissue along the tissue seal. A stop member550may be disposed at the distal end of one of the jaw members, e.g., jaw member520, to maintain a gap distance between the jaw members510and520during electrical activation to effectively seal tissue.

Alternatively and as shown inFIGS. 4B and 4C, the stop member550may operatively couple to a guide rail-system575that allows the jaw members510and520and the knife540to move forward over the fixed stop member550to sever tissue along the tissue seal. The knife540remains fixed relative to the jaw members510and520during distal movement of the jaw members510and520over the stop member550(seeFIG. 4C).

FIG. 5shows yet another embodiment of a cutting mechanism for forceps10and includes end effector assembly600having opposing jaw members610and620that are moveable relative to one another to engage tissue therebetween to effect a tissue seal. Jaw members610and620include respective jaw housings616and624that support electrically conductive surfaces612and622, respectively, that are each adapted to connect to an electrical energy source to conduct energy to tissue disposed between the jaw members to effectively seal tissue.

Each jaw member610and620includes an elongated perforation strip645aand645b, respectively, that extends inwardly from each respective electrically conductive surface612and622. The perforation strip645aand645bare aligned in general vertical registration relative to one another and each strip645aand645bincludes a series of teeth646aand646b, respectively, that are configured to intermesh with one another upon closure of the jaw members610and620. Alternatively, only one jaw member, e.g., jaw member620, may be configured to include the perforating strip645b.

In use, tissue is grasped between jaw members610and620and closed under a predetermined working pressure to effectively treat tissue, e.g., under a working pressure of about 3 kg/cm2 to about 16 kg/cm2 to seal tissue. The perforating strips645aand645bact to both grip the tissue for manipulation purposes and perforate the tissue along the center of the electrically conductive surface612and622. After electrosurgical activation of the electrically conductive surfaces612and622, the jaw members610and622are released revealing a perforated tissue line centrally-disposed between the conductive surfaces612and622. The surgeon thereafter tears the perforated tissue along the perforation to separate the two tissue halves.

The perforation strips645aand645bmay be insulative or electrically conductive depending upon a particular purpose or may be made from a reactive material which heats up during electrical activation to facilitate the perforation process.

From the foregoing and with reference to the various figure drawings, those skilled in the art will appreciate that certain modifications can also be made to the present disclosure without departing from the scope of the present disclosure. For example, it is contemplated that cutting mechanism may be dimensioned as a cutting wire or cutting blade that is selectively activatable by the surgeon to divide the tissue after sealing. More particularly, a wire or cutting blade is mounted within the insulator between the jaw members and is selectively energizable upon activation of a separate switch or simultaneously with the activation of the sealing switch.

Although the specification and drawings disclose that the electrically conductive surfaces may be employed to initially seal tissue prior to cutting tissue in one of the many ways described herein, it is also envisioned that the electrically conductive surfaces may be configured and electrically designed to perform any known bipolar or monopolar function such as electrocautery, hemostasis, and/or desiccation utilizing one or both jaw members to treat the tissue. Moreover, the jaw members in their presently described and illustrated formation may be energized or positioned to simply cut tissue without initially treating tissue which may prove beneficial during particular surgical procedures.