Vessel sealing instrument

ES 2 317 114 T3

DESCRIPTION

Instrument to seal vessels.

Background

The present invention relates to forceps used for open surgical procedures. More particularly, the present invention relates to a forceps that applies a combination of mechanical clamping pressure and electrosurgical current to seal tissue.

Technical field

A hemostat or forceps is a simple pincer-type tool that uses mechanical action between your jaws to constrict vessels and is commonly used in open surgical procedures to grasp, cut, and / or compress tissue. Electrosurgical forceps use both mechanical clamping action and electrical energy to perform hemostasis by heating tissue and blood vessels to coagulate, cauterize, and / or seal tissue.

Certain surgical procedures require sealing and cutting of blood vessels or vascular tissue. Some journal articles have described methods for sealing small blood vessels using electrosurgery. An article entitled "Studies on Coagulation and the Development of an Automatic Computerized Bipolar Coagulatof", J. Neurosurg., Volume 75, July 1991 describes a bipolar coagulator that is used to seal small blood vessels. The article states that it is not possible to safely coagulate arteries with a diameter greater than 2 to 2.5 mm. A second article entitled "Automatically Controlled Bipolar Electrocoagulation" - "COACOMp", Neurosurg. Rev (1984), pp. 187190, describes a method of interrupting electrosurgical energy to the vessel so that charring of the vessel walls can be avoided.

By using electrosurgical forceps, a surgeon can cauterize, coagulate / desiccate, reduce or retard bleeding, and / or seal vessels by controlling the intensity, frequency, and duration of electrosurgical energy applied to the tissue. Generally, the electrical configuration of electrosurgical forceps can be classified into two categories: 1) monopolar electrosurgical forceps; and 2) bipolar electrosurgical forceps.

Monopolar forceps utilize an active electrode associated with the clamping end effector and a remote patient return electrode or pad, which is typically attached externally to the patient. When electrosurgical energy is applied, the energy travels from the active electrode, to the operating site, through the patient, and to the return electrode.

Bipolar electrosurgical forceps use two generally opposed electrodes that are disposed on opposite interior surfaces of the end effectors and that are both electrically coupled to an electrosurgical generator. Each electrode is charged to a different electrical potential. Since tissue is a conductor of electrical energy, when effectors are used to grip tissue between them, electrical energy can be selectively transferred through tissue.

To perform a correct seal with large vessels, two predominant mechanical parameters must be precisely controlled - the pressure applied to the vessel and the gap between the electrodes, both of which affect the thickness of the sealed vessel. More particularly, the precise application of pressure is important to oppose the vessel walls, to reduce the impedance of the tissue to a value low enough to allow sufficient electrosurgical energy through the tissue, to overcome expansion forces during heating of the tissue. fabric and contribute to the final thickness of the fabric, which is an indication of a good seal. A fused vessel wall has been determined to be optimal between 0.0254 and 0.127 mm (0.001 and 0.005 inches).

Below this range the seal may shred or tear and above this range the lumens may not be properly or effectively sealed.

With respect to a small vessel, the pressure applied to the tissue tends to become less relevant, while the gap distance between the electrically conductive surfaces becomes more significant for effective sealing. In other words, the chances of two electrically conducting surfaces touching during activation increases as the vessels get smaller.

Electrosurgical methods can seal large vessels using an appropriate electrosurgical energy curve, coupled to an instrument capable of applying a large closing force to the vessel walls. The small vessel coagulation procedure is believed to be fundamentally different from that of electrosurgical vessel sealing. For the purposes of this specification, "coagulation" is defined as a process of tissue desiccation in which tissue cells are disrupted and dried and vessel sealing is defined as the process of liquefying collagen in the tissue so that it turn into a molten mass. Therefore, the coagulation of the small vessels is sufficient to permanently close them. Large vessels have to be sealed to ensure permanent closure.

Numerous bipolar electrosurgical forceps have been proposed in the past for various open surgical procedures. However, some of these designs may not provide a uniform reproducible pressure.

ES 2 317 114 T3 to the blood vessel and may result in an ineffective or non-uniform seal. For example, US Patent No. 2,176,479 to Willis, US Patent No. 4,005,714 and 4,031,898 to Hiltebrandt, US Patent No. 5,827,274; 5,290,287 and 5,312,433 to Boebel et al., US Patent Nos. 4,370,980; 4,552,143; 5,026,370 and 5,116,332 to Lottick, US Patent No. 5,443,463 to Stern et al., US Patent No. 5,484,436 to Eggers et al. and US Patent No. 5,951,549 to Richardson et al. all relate to electrosurgical instruments for coagulating, cutting and / or sealing vessels or tissue.

Many of these instruments include blade members or cutting members that simply cut tissue mechanically and / or electromechanically and are relatively ineffective for vessel sealing purposes. Other instruments rely only on clamping pressure to achieve the correct seal thickness and are not designed to take into account gap tolerances and / or parallelism and flatness requirements which are parameters that if properly controlled can ensure a tissue seal. consistent and effective. For example, it is known that it is difficult to adequately control the thickness of the resulting sealed tissue by controlling only the clamping pressure for either of two reasons: 1) If too much force is applied, there is a possibility that the two poles will touch and the energy will not. be transferred through the tissue, resulting in an ineffective seal; or 2) if too low a force is applied, a less reliable thick seal is created.

As mentioned before, to correctly and effectively seal large vessels, a greater closing force is required between the opposing jaw members. It is known that a large clamping force between the jaws typically requires a large pivot moment for each jaw. This is challenging because the jaw members are typically secured with pins that are positioned to have small moment arms relative to the pivot of each jaw member. A large force coupled to a small moment arm is undesirable because large forces can destroy the pins. Consequently, designers must compensate for these large closing forces by designing instruments with metal pins and / or designing instruments that at least partially discharge these closing forces to reduce the chances of mechanical failure. As can be appreciated, if metal pivot pins are employed, the metal pins must be insulated to prevent the pin from acting as an alternating current path between the jaw members which can be detrimental to effective sealing.

Increasing the closing forces between the electrodes can have other undesirable effects, for example, it can cause the opposing electrodes to come into intimate contact with each other, which can result in a short circuit and a small closing force can cause premature movement of the tissue during compression and prior to activation.

Therefore, there is a need to develop a bipolar forceps that effectively seals the vascular tissue and solves the problems mentioned above by providing an instrument that allows a large closing force between the opposing jaw members, reduces the chances of shorting the opposing jaws during activation and help manipulate, grasp, and retain tissue before and during activation.

US Patent 5,954,720 describes a bipolar electrosurgical instrument provided with a metal end effector and a ceramic end effector.

Compendium

The invention is defined by the independent claim, the preamble of which is based on WO 00/24330. The dependent claims are directed to preferred embodiments.

The present invention relates to a bipolar electrosurgical instrument for use in open surgery that includes a first and a second shaft, one of which can be connected to an electrosurgical power source. Each shaft includes a jaw member extending from its distal end and a handle disposed at its proximal end to effect movement of the jaw members relative to one another from a first open position, in which the jaw members are disposed spaced apart. one from the other, to a second closed position, in which the jaw members cooperate to grip the tissue between them. The electrical energy source produces a first and a second electrical potential in the respective jaw members, such that the jaw members are capable of selectively conducting energy through tissue held between them to make a seal.

Preferably, the first and second electrical potentials are created in the jaw members through the first axis. For example, in one embodiment, the first electrical potential is transmitted through the first shaft by a conductor having a terminal end that is electrically coupled to a distal connector that connects a first jaw member to the first electrical potential. The second electrical potential is transmitted through the first axis by means of a tube arranged within the first axis that connects the second jaw member to the second electrical potential.

The first and second jaw members are connected around a pivot pin. The distal connector is preferably interposed between the jaw members and includes a series of flanges that are dimensioned to prevent the emanation of leakage currents from the electrically conductive sealing surfaces of the jaw members during activation.

ES 2 317 114 T3

The distal connector includes a spring washer or wave washer that acts as an electrical intermediary between the terminal end and the jaw member. In one embodiment, the spring washer is chamfered to improve the electrical interface between the terminal end and the jaw member, that is, the chamfer causes the spring washer to rotate relative to the terminal end during movement of the jaw members from the first. to the second position, which provides self-cleaning and improved operating electrical contact between the terminal end and the jaw member.

Preferably, the distal connector is made of an insulating substrate and is disposed between the jaw members for electrical isolation of the first and second potentials. In one embodiment, the distal connector includes a first surface having at least one cavity defined therein that is dimensioned to receive at least a portion of the terminal end of the conductor.

In still another embodiment, one of the jaw members includes a flange that is dimensioned to prevent exposure of the terminal end during all angles of operation, that is, when the jaw members are arranged in the first position, the second position, and / or during operation movement between them.

The conductor preferably includes an inner core made of an electrically conductive solid or multi-stranded material, eg copper / aluminum wire that is surrounded by a non-conductive insulating coating, eg plastic. In one embodiment, the terminal or distal end of the electrically conductive material is flattened, ie, "flat shaped," and is dimensioned to substantially enclose a protrusion extending from the surface of the distal connector. Preferably, the boss is designed to electrically isolate the terminal end of the conductor from the pivot pin.

In another embodiment, at least one non-conductive stop member is disposed on an electrically conductive sealing surface of one of the jaw members. The stop members are designed to control / regulate the distance, ie the gap, between the jaw members when tissue is held between them during activation.

Brief description of the drawings

Various embodiments of the subject instrument are described herein with reference to the drawings in which:

Fig. 1 is a perspective view from the left of a forceps according to the present description;

fig. 2 is an enlarged, perspective view of an end effector assembly of the forceps of Fig. 1 shown in the open configuration;

fig. 3 is an enlarged perspective view of the end effector assembly of the forceps of Fig. 1 shown in the closed configuration;

fig. 4A is an exploded view of the forceps according to the present invention;

fig. 4B is an enlarged, exploded view of the end effector assembly of FIG. 4A, showing the electrical connection of a distal electrical connector for supplying electrical power to the end effector assembly;

fig. 5 is an enlarged, top perspective view of a lower jaw member of the forceps with the distal connector seated thereon;

fig. 6 is a right perspective view of the forceps of Fig. 1 shown grasping a tissue structure;

fig. 7 is an enlarged view of the indicated area of ​​detail in Fig. 4A, showing a proximal electrical connector / interface for supplying power to the end effector assembly; and fig. 8 is a cross section of the forceps of Fig. 6 showing the electrical feed path of a first conductor having a first electrical potential and showing the electrical connection of the proximal electrical interface of Fig. 7 with a second conductor that has a second electric potential.

Detailed description

Referring now to Figures 1-4, a forceps 10 for use with open surgical procedures includes elongated shaft portions 12a and 12b, each of which has a proximal end 16a and 16b, respectively, and a distal end 14a and 14b. , respectively. In the drawings and in the descriptions that follow, the term "proximal" refers, as is traditional, to the end of the forceps 10 that is closest to the user, while the term "distal" refers to the end that is furthest from the user. Username.

ES 2 317 114 T3

Forceps 10 includes an end effector assembly 100 that is attached to distal ends 14a and 14b of shafts 12a and 12b, respectively. As explained in more detail below, end effector assembly 100 includes a pair of opposing jaw members 110 and 120 that are pivotally connected about pivot pin 151.

Preferably, each shaft 12a and 12b includes a handle 17a and 17b disposed at its respective proximal end 16a and 16b, each defining a finger hole 18a and 18b, respectively, to receive therethrough a user's finger. As can be appreciated, finger holes 18a and 18b facilitate movement of shafts 12a and 12b relative to each other which, in turn, pivot jaw members 110 and 120 from an open position (Fig. 2), in which the jaw members 110 and 120 are disposed apart from one another, to another clamping or closed position (Fig. 3) in which the jaw members 110 and 120 cooperate to grip the tissue 400 between them (Fig. 6).

A ratchet 30 is preferably included for selective locking of jaw members 110 and 120 relative to each other in various positions during pivoting. As seen more clearly in Fig. 6, a first ratchet interface, for example 30a, extends from proximal end 16a of shaft member 12a toward a second ratchet interface 30b generally vertically aligned, such that the interior facing surfaces of each ratchet 30a and 30b abut each other in the closure around fabric 400. Preferably, each ratchet interface 30a and 30b includes a plurality of flanges 32a and 32b, respectively, projecting from the inward facing surface of each ratchet interface 30a and 30b, such that the ratchet interfaces 30a and 30b meet. lock each other in at least one position. In the embodiment shown in Fig. 6, the ratchet interfaces 30a and 30b lock together in different positions.

Preferably, each position associated with cooperating ratchet interfaces 30a and 30b maintains a specific, i.e. constant, deformation energy in shaft members 12a and 12b, which in turn transmits a specific closing force to jaw members 110 and 120. It is envisioned that the ratchet 30 may include graduations or other visual markings that allow the user to easily and quickly determine and control the amount of locking force desired between the jaw members. A design without a ratchet system or similar system would require the user to hold the jaw members 110 and 120 together by applying a constant force to the handles 17a and 17b, which could lead to erroneous results.

As illustrated more clearly in Fig. 1, one of the shafts, for example 12b, includes a proximal shaft connector 19 that is designed to connect the forceps 10 to an electrosurgical power source, such as an electrosurgical generator ( not shown). More particularly, the proximal shaft connector 19 is formed by a cover 19a and a flange 19b extending proximally from the shaft 12b. Preferably, cover 19a and flange 19b mechanically cooperate to secure an electrosurgical cable 210 to forceps 10, such that the user can selectively apply electrosurgical energy as needed.

The proximal end of cable 210 includes a plug 200 having a pair of pins 202a and 202b that are dimensioned for electrically and mechanically engaging the electrosurgical power generator. As will be explained in more detail below with respect to FIG. 8, the distal end of wire 210 is secured to the proximal shaft connector 19 of shaft 12b by a plurality of finger-type clamping members 77a and 77b and a crimp crimp. cable having opposing fingers 76a and 76b. The interior of cable 210 houses a pair of conductors 210a and 210b that conduct the different electrical potentials from the electrosurgical generator to jaw members 110 and 120 as explained in greater detail below.

As seen more clearly in Figures 2-4B, the two opposing jaw members 110 and 120 of end effector assembly 100 are pivotal about pin 151 from the open position to the closed position to grip tissue 400 between them. Jaw members 110 and 120 are generally symmetrical and include similar component features that cooperate to allow easy rotation about pivot pin 151 to grip and seal tissue 400. Accordingly and unless otherwise noted, the jaw member 110 and the operating characteristics associated therewith will be initially described in detail herein and similar component characteristics with respect to the jaw member 120 will be briefly summarized below.

Jaw member 110 includes an insulated outer casing 114 that is dimensioned to mechanically engage an electrically conductive sealing surface 112 and a proximally extending flange 130 that is dimensioned to seat a distal connector 300 which is described in more detail. below with respect to Figures 4A, 4B and 5. Preferably, outer insulating housing 114 extends the entire length of jaw member 110 to reduce AC or leakage current paths during incidental sealing and / or burning of tissue 400. The interior facing surface Flange 130 includes an electrically conductive plate 134 (FIG. 4B) that conducts electrosurgical energy to electrically conductive sealing surface 112 upon activation.

Similarly, jaw member 120 includes similar elements including: an outer casing 124 that engages an electrically conductive sealing surface 122; a proximally extending flange 140 that seats the opposite face of distal connector 300; an electrically conductive plate 144 that conducts electrosurgical energy to the electrically conductive sealing surface 122 upon activation.

One of the jaw members, for example 110, is envisioned to include at least one stop member 150 disposed on the inwardly facing surface of the electrically conductive sealing surface 112 (and / or 122).

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The stop member (s) is (are) preferably designed to facilitate grasping and manipulation of tissue 400 and define a gap "G" (Fig. 6) between opposing jaw members 110 and 120 during sealing. A detailed discussion of these and other anticipated stop members 150, as well as various fabrication and assembly procedures for securing, discarding, depositing, and / or securing stop members 150 to electrically conductive sealing surfaces112, 122 are described in commonly assigned and pending US Application Serial No. 10 / 338,953 entitled "Bipolar Electrosurgical Forceps with Non-conductive Stop Members" published as US 2003 181910.

FIG. 4A shows an exploded view of the various components of forceps 10 and the operating relationships between them. More particularly and in addition to the components described above with respect to the preceding Figures 1-3, the shaft 12a is preferably hollow to define a longitudinal channel 15a disposed therethrough having dimensions to receive a tube 6a therein. Tube 60a includes a proximal end 64a, a distal end 62a, and at least one mechanical interface 61a disposed therebetween. Shaft 12a also includes a cover plate 50 that is designed for a press fit application within an opening / cavity 45a defined through the outer surface of shaft 12a. Cover plate 50 includes a series of opposing flanges 51a and 51b extending therefrom that are dimensioned to secure tube 60a within shaft 12a as described below. A second flange 52 secures the cover plate 50 to the shaft 12a.

During assembly, proximal end 64a of tube 60a is slidably incorporated into channel 15a so that mechanical interface 61a is balanced for engagement with cover plate 50. Cover plate 50 is then snapped on. within cavity 45a, such that flanges 51a and 51b secure tube 60a within shaft 12a. It is envisioned that the cavity 45a of the shaft 12a may include at least one pawl (not shown) that engages the mechanical interface 61a disposed along the outer surface of the tube 60a to limit / prevent the rotation of the tube 60a with respect to the axis. 12a, This cooperative relationship is shown by example with respect to fasteners 75a and 75b and interfaces (eg notches) 61b of shaft 12b in Fig. 8. In this case, flanges 51a and 51b (like flanges 42a and 42b of cover plate 40 in Fig. 8) retain fasteners 75a and 75b in Fig. 8 in secure engagement within the notch (s) ( s) 61a to prevent rotational and / or longitudinal movement of tube 60a within channel 15a.

Preferably, the most proximal end of tube 60a includes a slot-type interface 65a that mechanically engages a corresponding tab 88a extending from the inner surface of shaft 12a within cavity 45a. The tab 88a is intended to also prevent rotational movement of the tube 60a within the axis 12a. Alternatively, a slot 65a may be formed to allow radial contraction and expansion of tube 60a to facilitate friction fit application between tube 60a and shaft 12a. Other interfaces are also envisaged that facilitate the application of shaft 12a and tube 60a, for example, press fit, spring lock, locking tabs, screw type interface, tongue and groove, etc.

Distal end 62a of tube 60a is preferably sized to engage jaw member 120, that is, distal end 62a includes a slot-type interface 66a that facilitates simple, secure friction-fit engagement of tube 60a with jaw member. 120. More particularly and as mentioned above, jaw member 120 includes a proximally extending flange 130 having sleeve 128 extending proximally therefrom and which is dimensioned such that upon insertion of sleeve 128 into distal end 62a , the slot-type interface 66a expands radially outwardly and securely locks the jaw member 120 to the tube 60a. Again, other fixing methods are envisaged that could serve the same purpose, for example, snap-fit ​​locks, locking tabs, spring locks, screw-type interface, tongue and groove, etc.

As can be appreciated from the present description, the arrangement of shaft 12b is slightly different from that of shaft 12a, as seen more clearly in Figures 4B, 7 and 8. More particularly, shaft 12b is also hollow to define a channel 15b through it and is sized to receive a tube 60b therein. Tube 60b includes a proximal end 64b and a distal end 62b that are generally similarly attached to their mating components with respect to axis 12a. For example, proximal end 64b of tube 60b is slidably incorporated into channel 15b, such that a mechanical interface 61b disposed on the outer surface of tube 60b is balanced for engagement to a cover plate 40 (Figures 4A and 8 ).

Preferably and since forceps 10 is uniquely designed to incorporate all electrical connections and interfaces within and along a single axis, eg, 12b, axis 12b includes a slightly larger cavity 45b defined therein to house and secure the various electrical connections associated with forceps 10, as defined above. For example, cover plate 40 is dimensioned slightly differently from cover plate 50 for the most part due to spatial considerations that must be taken into account for incorporation of the various internally arranged electrical connections. However, cover plate 40 snaps onto shaft 12b, such that a pair of flanges 42a and 42b secure tube 60b within shaft 12b in a similar manner as described above. For example, Fig. 8 shows a pair of fasteners 75a and 75b disposed within cavity 45b of shaft 12b that engage a corresponding number of mechanical interfaces 61b disposed along the outer surface of tube 60b to limit / prevent the rotation of tube 60b with respect to axis 12b. When assembled, each flange 42a and 42b is pushed into a corresponding slot 73a and 73b, respectively, which effectively hold / retain fasteners 75a and 75b in secure engagement within notches 61b to prevent rotational and / or longitudinal movement. of tube 60b into channel 15b.

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End 64b of tube 60b also includes a slot-type interface 65b that mechanically engages a corresponding tab 88b extending from the inner surface of shaft 12b within cavity 45b. Tab 88a is intended to also prevent rotational movement of tube 60b within axis 12b. Alternatively, slot 65b may be formed to allow radial contraction and expansion of tube 60b to promote friction fit application between tube 60b and shaft 12b.

Unlike tube 60a, tube 60b is designed as an electrical conduit for transmitting electrosurgical energy to jaw member 110, which is discussed in more detail below with respect to Figures 7 and

8. Distal end 62b of tube 60b is preferably sized to engage jaw member 110, that is, distal end 62b includes a slot-type interface 66b that facilitates simple, secure friction fit engagement of tube 60b with the jaw member. 110. This is illustrated more clearly in FIG. 4B showing flange 130 extending proximally of jaw member 110 having an end sleeve 138 extending therefrom. End sleeve 138 is dimensioned such that as end sleeve 138 is inserted into distal end 62b, slot-type interface 66b expands radially outward and securely locks jaw member 110 to tube 60b.

As can be appreciated, terminal end 138 is made at least partially of an electrically conductive material so that an electrosurgical potential is effectively conducted from tube 60b, through terminal sleeve 138, through plate 134 and into the tube. electrically conductive sealing plate 112 upon activation. As mentioned above, the outer insulating housing 114 of the jaw member 110 effectively eliminates electrical leakage currents and incidental tissue burning through the projected electrical path.

As seen more clearly in FIG. 4B, jaw member 110 includes a conduit channel 135 that extends proximally from flange 130 that includes end sleeve 138 at its most proximal end. End sleeve 138 connects to conduit tube 60b disposed within shaft 12b as described above. Conduit 135 serves two purposes: 1) to provide electrical continuity from terminal sleeve 138, through electrically conductive plate 134 and to electrically conductive sealing surface 112; and 2) providing a channel to guide lead 210a to distal connector 300 as described below.

The insulated outer casing 114 is dimensioned to securely engage the electrically conductive sealing surface 112. It is envisioned that this can be accomplished by stamping, by overmolding, by overmolding of an electrically conductive stamped sealing plate and / or by overmolding of a metal injection molded sealing plate. All of these manufacturing techniques produce an electrode having an electrically conductive surface 112 that is substantially surrounded by an insulated outer casing 114.

It is envisioned that the jaw member may also include a second insulator (not shown) disposed between the electrically conductive sealing surface 112 and the outer insulated housing 114. The insulated outer casing 114 and the electrically conductive sealing surface 112 (and the other insulator if used) are preferably sized to limit and / or reduce many of the known undesirable effects related to tissue sealing, eg, discharges. disruptive, thermal extension and leakage current dissipation.

It is also envisioned that the electrically conductive sealing surface 112 may include a constriction arrangement (not shown) that facilitates the secure application of the electrically conductive surface 112 to the insulated outer casing 114 and also simplifies the entire fabrication procedure. . It is also contemplated that the electrically conductive sealing surface 112 may include an outer peripheral edge having a radius and the insulated outer casing 114 meets the electrically conductive sealing surface 112 along an adjacent edge that is generally tangential to the radius and / or along the radius. Preferably, at the interface, the electrically conductive surface 112 is elevated relative to the insulated outer casing 114. These and other anticipated embodiments are discussed in US application Serial No. 10 / 474,168, filed herewith, commonly released and pending, titled "Electrosurgical Instrument Reducing Collateral Injury to Adjacent Tissue" by Jonson et al., published as US 2005 021 025.

As most clearly illustrated in the exploded view of Fig. 4B, the inner periphery of tube 60b is preferably dimensioned to accommodate conductor 210a therethrough, so that an electrically different potential can be efficiently transmitted. jaw member 120. More particularly and as mentioned above, cable 210 houses two conductors 210a and 210b having different electrical potentials. The first conductor 210a is disposed through the tube 60b and conducts the first electrical potential to the jaw member 120, as described in more detail below. Second conductor 210b is electrically coupled to tube 60b at a proximal connector 80 (FIG. 7) that includes a series of electrical crimps 85, 87, and 89 to secure conductor 210b to tube 60b. As a result, tube 60b carries the second electrical potential therethrough for final connection to jaw member 110 as defined above.

Conductor 210a preferably includes an insulating coating 213 that surrounds an inner core or electrical conductor 211 (eg, wire) disposed therein to isolate electrical conductor 211 from tube 60b during activation. It is envisioned that the wire 211 may be made of an electrically conductive solid or multi-stranded material, for example copper / aluminum that is surrounded by a non-conductive insulating coating 213, for example plastic.

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Wire 211 includes a terminal end 212 that is dimensioned to electrically couple with jaw member 120. Preferably, terminal end 212 is "flat-shaped" in a generally arcuate shape to enclose a corresponding projection 314 extending upwardly from the distal connector 300 toward jaw member 120, as described above. The distal connector 300 is envisioned to perform at least two functions : 1) isolate the jaw member 110 from the jaw member 120; and 2) providing a working electrical connection for conductor 210a to jaw member 120.

More particularly, the distal connector 300 is generally shaped to mate with the entire profile of the electrically conductive faceplates 134 and 144 of the jaw members 110 and 120, respectively, so that upon assembly, the outer surfaces 302 and 304 of distal connector 300 abut against corresponding plates 134 and 144 of jaw member 110 and 120, respectively. The exterior facing surface 302 of distal connector 300 is envisioned to act as a driving surface that facilitates pivotal movement of jaw member 120 about pivot pin 151 relative to jaw member 110. Preferably, distal connector 300 it is made of an insulating substrate such as plastic or some non-conductive material.

The distal connector includes a series of flanges 322 and 326 that extend toward jaw member 120 and a second series of flanges 324 and 328 that extend toward jaw member 110. These flanges 322, 324, 326, and 328 isolate the other operating components of forceps 10 and the patient from electrical leakage currents emanating from electrically conductive plates 134 and 144 during activation. Flanges 322 and 328 may also be dimensioned to limit / restrict expansion of tissue 400 beyond sealing surfaces 112 and 122 during activation. Flanges 326 and 324 are preferably sized to isolate the forceps during all angles of operation, ie, pivoting of jaw members 110 and 120.

As mentioned above, distal connector 300 includes a protrusion 314 that extends toward jaw member 120 and is dimensioned to secure terminal end 212 of lead 210a. Preferably, the boss is designed to electrically isolate the terminal end of the conductor from the pivot. The boss 314 preferably defines an opening 316 therethrough to receive the pivot pin 151 and allow pivotal movement of the jaw member 120 about the pivot 151 and the boss 314 relative to the jaw member 110.

A continuous series of cavities 312, 318, and 319 are formed around and proximate boss 314 to seat flat-shaped terminal end 212, wire 211, and insulated portion of conductor 210a, respectively. This also secures lead 210a to the distal connector and limits movement of the distal connector (210a). In some cases it may be preferable to include a piece of silicone or other non-conductive material in the joint between the wire and the terminal end 212 as an added and / or alternative insulating protection. It is also envisioned that flange 326 may include a notch (not shown) disposed therethrough, which facilitates mounting of lead 210a on distal connector 300. As can be appreciated, this eliminates the step of forming arcuate end 212 upon insertion through channel 318. As mentioned above, a piece of silicone or the like can be added over / into the notch for isolation purposes. after terminal end 212 is seated within distal connector 300.

The most proximal portion of the distal connector 300 includes a finger 320 that is dimensioned to seat within a channel 137 formed within the conduction channel 135, such that the distal connector 300 moves in connection with the jaw member 110 during pivoting. Channel 135 may be formed during a molding process, subsequently drilled after conduit channel 135 has been formed, or by any other known forming method. The uppermost edge of protrusion 314 is preferably sized to seat within a corresponding cavity (not shown) formed within plate 144. Likewise and although not shown, the opposite end of protrusion 314 is envisioned to extend toward plate 134 and is seated within a cavity 131 formed within plate 134. Cavity 131 is envisioned to facilitate engagement of distal connector 300 to jaw member 110.

Distal connector 300 also includes a spring washer or wave washer 155 that is preferably sized to enclose boss 314 on terminal end 212. In assembly, washer 155 is interposed / wedged between terminal end 212 and conductive plate 144 of the jaw member 120. Washer 155 is intended to improve the connection between the terminal end and plate 144. More particularly, washer 155 is preferably shaped such that washer 155 provides self-cleaning and electrical operating contact between terminal end 212 and jaw member 120. It is contemplated that washer 155 "self-cleaning" due to frictional contact and friction. relative movement of washer 155 with respect to terminal end 212 during pivoting of jaw members 110 and 120. The self-cleaning action can be attributed to washer 155 rubbing, scratching, and / or digging against terminal end 212 and / or plate 144 during pivoting of jaw members 110 and 120.

The outer casing of each of the jaw members 110 and 120 preferably includes a further cavity or circular groove 129 that receives a ring-type insulator 153b and 153a, respectively. Insulators 153a and 153b isolate pivot pin 150 from jaw members 110 and 120 when forceps 10 is mounted. Preferably, pivot pin 150 is hammered to secure jaw members 110 and 120 during assembly and may include outer flanges 151a and 151b, at least one being hammered or hammered.

ES 2 317 114 T3 formed after jaw members 110 and 120 are mounted around pivot pin 150, as seen more clearly in FIG. 4B.

On activation, the first electrical potential is carried by conductor 210a through tube 60b to terminal end 212. Washer 155 of distal connector 300 then conducts the first potential to face plate 144 which carries the first potential to the end plate. seal 122 disposed on the inward facing surface of jaw member 120. The second potential is carried by conductor 210b which is electrically coupled to tube 60b (via crimps 85, 87, and 89) to conduct the second potential to terminal sleeve 138 of jaw member 110. Terminal sleeve 138 is electrically connected to the sealing surface 112 through faceplate 134.

LaFig. 8 shows the connection of cable 210 within cavity 45b of shaft 12b. As mentioned before, a series of finger-like elements 77a and 77b and crimps 76a and 76b secure cable 210 within shaft 12b. Preferably, cable 210 is secured at an angle alpha (a) relative to a longitudinal axis "A" disposed along axis 12b. It is envisaged that tilting the cable 210 in an inward direction, that is, towards the axis 12a, facilitates the handling of the forceps 10 and the cable 210 during surgery, that is, the inclined arrangement of the cable 210 when it exits the forceps 10. tends to reduce cable tangling and / or cable interference during handling.

Preferably at least one of the jaw members 110 and 120 includes a flange-like feature 126 and 136, respectively, that is dimensioned to prevent exposure of the terminal end 212 or wire 211 during all angles of operation, that is, when the jaw members 110 and 120 are arranged in the first open position, the second closed position, and / or during operating movement between them.

It is envisioned that by making the forceps 10 disposable, the forceps 10 is less likely to be damaged since it is designed for single use, and therefore does not require cleaning or sterilization. Consequently, the functionality and consistency of vital sealing components, for example conductive surfaces 112 and 122, stop member (s) 150, and insulated housings 124 and 114 will ensure a quality, uniform seal.

From the foregoing and with reference to the various figures in the drawing, those skilled in the art will appreciate that certain modifications can be made to the present invention without departing from the scope of the present invention. For example, it may be preferable to include a tail that facilitates manipulation of the forceps 10 during surgery.

Furthermore, although the electrical connections are preferably incorporated with the lower shaft 12b and the instrument is intended for use with the right hand, it is contemplated that electrical connections may be incorporated with the other shaft 12a depending on a particular purpose and / or facilitate the left-handed user manipulation.

It is also contemplated that a contraction tube may be employed over proximal connector 80 and / or the various other soldered and / or crimp connections 85, 87 and 89 associated with proximal connector 80 cooperate with connector wire 210b. This provides additional insulation protection during assembly. It is also contemplated that the forceps 10 (and / or the electrosurgical generator used in connection with the forceps 10) may include a sensor or feedback mechanism (not shown) that automatically selects the appropriate amount of electrosurgical energy to effectively seal the tissue 400 of particular size gripped between jaw members 110 and 120. The sensor or feedback mechanism may also measure impedance through the tissue during sealing and provide an indicator (visual and / or audible) that an effective seal has been created between jaw members 110 and 120.