WO1999045854A1

WO1999045854A1 - Conjunctive electrosurgical device

Info

Publication number: WO1999045854A1
Application number: PCT/US1999/004476
Authority: WO
Inventors: Mark A. De Stefano; Glenn H. Stahl; W. Keith Stoneback; David C. Downey
Original assignee: Surgical Laser Technologies, Inc.
Priority date: 1998-03-12
Filing date: 1999-03-02
Publication date: 1999-09-16
Also published as: WO1999045854A9; AU2976699A

Abstract

The present invention provides an electro-surgical device (14) by which electrical energy, typically radio frequency, can be affixed to or integrated with a disposable or reposing surgical instrumentation (4). The electro-surgical device comprises an electrode arrangement (32) having a first end for connection to an electro-surgical generator (18), a second end remote from the first end for engaging tissue to be electro-surgically treated, and a carrier (22) overlying at least some portion of the external surface of the primary instrument (4). The carrier (22) supports the electrode arrangement (32) and positions the electrode arrangement at a location on or in the external surface of the primary instrument (4).

Description

CONJUNCTIVE ELECTROSURGICAL DEVICE

Field of the Invention The present invention relates generally to electrosurgical devices. More particularly, the present invention relates to an electrosurgical device for use in conjunction with a non-electrosurgical device through either permanent affixation to the non-electrosurgical device or integration therewith.

Background of the Invention Surgeons have a wide variety of instruments to use in performing surgery. Some instruments, as for example scalpels, have no external power source other than the surgeon's own hand. A number of other such mechanical instruments have moving parts that are driven by an external power source. Among such instruments are atherectomy devices used for opening clogged blood vessels in cardiovascular surgery and debriders for use on polyps in ear, nose and throat surgery. Still other instruments deliver special forms of energy to the tissue to be treated. Such other instruments include, for example, surgical laser systems, cryosurgical systems, and electrosurgical systems.

Surgeons frequently turn to electrosurgical ("ESU") systems to cut and/or coagulate tissue, and often do so to supplement other instruments they may be using. Electrosurgical systems can be particularly effective in stanching blood ("hemostasis") from severed vessels ("bleeders") of all sizes up to approximately 2 mm in diameter, as are often encountered in surgery. Hemostasis through ESU capability reduces the number of occasions that time- consuming and cumbersome ligatures must be used to tie off such bleeders. Electrosurgical systems can be especially effective for bleeders in areas difficult to reach and in endoscopic or minimally invasive procedures. If hemostasis is promptly effected, then the patient benefits from less blood loss and the surgeon benefits from a clearer field of view.

Still, if ESU systems are used in conjunction with other instrumentation, it can be cumbersome and time-consuming in endoscopic procedures to withdraw the other instrumentation, introduce the ESU system, use it, then withdraw it, and finally re-introduce the other instrumentation. Minimizing the time that the patient is undergoing any surgical procedure minimizes the attendant risks. Coupling ESU capability to other instrumentation would help minimize the time in the operating room, since less time is spent in switching instruments . When the underlying instrumentation is a powered cutting device operating in a blood-rich environment, surgical complications arising from bleeding can become acute and at times force a premature conclusion to the procedure. Prompt hemostasis can reduce such complications.

It can also be important to the surgeon to have a dedicated and controlled path for the delivery and return of the electric energy. Monopolar ESU capability depends upon grounding pads contacting the patient's buttocks in order to complete the return circuit of the electrical energy. The electrical energy will take the path of least resistance from the active, delivery electrode to the grounding pad; such path may pass through organs and tissues best left untraversed by the electrical energy. Similarly, if the electrical energy is delivered to or returned from the surgical site by using other instrumentation to double as a conductive path, a greater risk of leakage, capacitance and inductance results, if special precautions are not taken.

It is also important that the surgeon should not have to relearn or to compromise in how the non-electrosurgical instrument is used, especially in endoscopy, simply in order to gain prompt hemostasis. The ESU capability should not interfere with the use of the other instrument or disturb the surgeon's line of sight

Several known systems have included ESU capability with other surgical instruments. Some of these are disclosed and described in the following U.S. Patents and other prior art:

US Patent No. 4,375,218 to DiGeronimo discloses a combination scalpel and forceps which may apply a monopolar ESU capability. The scalpel is retractable to the interior surface of one of the arms of the forceps. Electric current can be passed through the forceps arms to the tips of the forceps so that the tips, when gripping tissue, can coagulate the tissue under pressure.

US Patent No. 4,640,279 to Beard discloses a combination surgical scalpel and monopolar electrosurgical instrument. The device includes an electrode, the tip of which is canted away from the scalpel blade. The tip of the scalpel projects beyond the tip of the electrode. The back of the scalpel blade is clipped to the shank of the electrosurgical electrode. The connection between the shank of the electrode and the back of the scalpel thus forms an axis of rotation. By rotating the instrument 180 degrees about the axis, the user can bring the electrode or the scalpel into contact with the tissue of interest. The scalpel and electrode form a single, disposable item. While suitable for open surgery, this invention is unsuitable for endoscopic surgery.

US Patent No. 4,651 ,734 to Doss et al. discloses in combination a surgical instrument that uses pressure on the tissue to cut (e.g. scalpel) and an electrosurgical electrode. The electrode is attached by means of bulky clips to the back of the scalpel which allows adjustment of the electrode. The pressure- cutting means also acts as an electrosurgical electrode that is the bipolar counterpart to the other electrode. The tip of the electrode and the tip of the scalpel terminate abreast of each other. This invention though suitable for open surgery is unsuitable for endoscopic surgery.

An electrode assembly that can be detachably combined with an aspiration/ irrigation cannula is disclosed in US Patent No. 5,662,647 to Crow et al. The electrode assembly slides within the cannula to reach the surgical site. The patent also discloses an electrosurgical method employing the apparatus described in the patent. The electrode assembly has the disadvantage that it uses up valuable space in the cannula, and does little to conform its structure to the structure of the cannula.

US Patent No. 5,164,945 to Long et al. describes a tapered laser probe that has adjunctive ESU capability. The mid-section of the probe has a zone encircling the taper that is coated with a conductive element that has enough resistance to generate ohmic heating from current supplied by electrical leads. Using ohmic heating, this device heats a broad zone, rather than passing current in a more controlled fashion between two discrete contact points; this device also maladroitly locates the zone in the middle of the taper, as opposed to adjacent the operative region of the probe, thus making it difficult to engage the tissue of interest.

US Patent No. 5,647,867 to Neuberger et al. describes a side-fire laser probe that has an internally retractable loop scraper. The laser first coagulates a broad swath of tissue; the scraper being an ohmically heated wire, resects the tissue that has just been coagulated. The scraper demands a significant amount of internal space within the device. Further, neither the scraper nor the laser probe offers selective, spot coagulation.

Alternative current pathways for a bipolar surgical cutting tool are disclosed in US Patent No. 5,531 ,744 to Nardella et al. A drawback from such a device is if the user decides to use the stapler as electrosurgical electrodes, than all the tissue within the stapler is coagulated, whether or not it is required. It does not lend itself to selective, spot coagulation.

US Patent No. 4,862,890 to Stasz et al. discloses an electrode arrangement that has a ceramic substrate that serves as an insulative layer between an active and a return electrode. The substrate is shaped and tapered like a spatula, surrounded by an edge that is blunt, and not sharp. Metallized patterns are placed onto the ventral and dorsal sides of the substrate, up to the blunt edge, which is ground to be free of metal traces. This invention cuts tissue by the flow of electrical energy from one metallized side of the substrate, over the blunt edge, to the other metallized side. The blunt edge, being ceramic and therefore able to withstand greater heat than a metal edge, provides incidental coagulation to the cut tissue, though it does so through thermal conduction, and not by electrical flow. In this invention, the primary — and only — instrument is the electrosurgical device, which is designed to be a cutter for use in open surgery. Moreover, this instrument does not offer selective, spot coagulation.

US Patent No. 5,514, 134 to Rydell et al. discloses a bipolar electrosurgical scissors. A layer of non-conductive material is applied to surfaces of the underlying blade members, thereby insulating and defining the coacting blade surfaces that act as bipolar electrodes. A drawback of this device is that if the user decides to use the scissors as electrosurgical electrodes, than all of the tissue within the scissors is coagulated whether required or not. A further drawback is that by insulating the coacting scissors with ceramics, the structure and functionality of the non-electrosurgical instrument is altered in order to accommodate the ESU adjunct. US Patent No. 5,389,104 to Hahnen et al. discloses an arthro- scopic jaw arrangement housed by a hollow tube. The jaws act as a surgical cutter, but can be adapted to act as a punch. An electrical current is supplied to the jaws through the tube and thus provides monopolar ESU capability to the jaws. The tube is insulated by means of plastic or ceramic that is shrink-wrapped onto the tube. If the user decides to use the jaws as electrosurgical electrodes, then all the tissue within the jaws is coagulated, whether it requires coagulation or not.

On balance, each of the devices known in the prior art suffers from one or more drawbacks. A number of the devices fail to control the flow of electrical energy through dedicated conduits, relying on monopolar ESU capability and/or dragooning other instruments into service as conductive paths without special precautions. In other devices, the ESU capability lacks precise coagulation, thereby causing a less discriminate necrosis. Yet other devices deploy the ESU capability such that it cannot be simply and readily brought to the surgical site. Some other devices are so constructed that the ESU capability interferes with the line of sight or the operation of the other instrument. Indeed, in some devices, the demands imposed by ESU capability compel the underlying instrument to be constructed of suboptimal materials. What is needed is a device that can address all these shortcomings, and be robust enough and safe enough to meet increased demands imposed by powered instrumentation used in endoscopy.

It is therefore desirable to have an ESU device which can be economically manufactured and integrated with and/or affixed to another instrument before use in the sterile surgical field. Permanently affixing the ESU device to the other instrument enables safe, immediate, and conjunctive use when necessary.

Summary of the Invention The present invention provides an electrosurgical device by which electrical energy, typically at radio frequency, can be affixed to or integrated with a disposable or resposable surgical instrument and used concurrently therewith.

The present invention comprises an electrosurgical device for application to or integration with a primary, non-electrosurgical instrument. The present invention comprises an electrode arrangement having a first end for connection to an electrosurgical generator and a second end remote from the first end for engaging tissue to be electrosurgically treated, and a carrier lying on or in an external surface of the primary instrument. The carrier supports the electrode arrangement and positions the electrode arrangement at a location on the external surface of a disposable or resposable portion of the primary instrument, such location being adjacent an operative region thereof. The carrier thereby brings the second end of the electrode arrangement into close proximity with tissue being operated on by the primary instrument, whereby a person operating the primary instrument can treat tissue by a selected one of the electrode arrangement and the primary instrument.

The term "primary instrument" is not intended to describe the non- electrosurgical instrument as having a greater importance or as necessarily being used before the ESU device. The term is merely meant to generically label an instrument which can be used in conjunction with the ESU device. The present invention provides an electrosurgical device constructed such that it can be affixed to or integrated with other surgical instruments without degrading the visibility of the surgical field or interfering with the operation of the primary instrument, especially in endoscopy. The ESU capability should add little extra weight to a surgeon's handpiece as any additional weight contributes to fatigue.

The present invention also provides an ESU device which controls the flow of electrical energy and can accurately enable a surgeon to coagulate selected, discrete areas of tissue through quick and simple direction of the device to the tissue that requires coagulation. The present invention further provides an ESU device which, when affixed to a portion of the primary instrument that is designed for a single use (disposable) or for limited use (resposable) can be effectively used for as many times as the primary instrument and therein by necessity providing an ESU device which can be resterilized for reuse.

Brief Description of the Drawings

For the purpose of illustrating the invention, there are shown in the drawings forms which are presently preferred; it being understood, however, that this invention is not limited to the precise arrangements and instrumentalities shown. Figure 1 illustrates a surgical system incorporating the present invention including a primary surgical instrument and an electrosurgical device.

Figures 2A-2C illustrate an enhanced side view, bottom view, and front view, respectively of the ESU device of Figure 1. Figures 3A-3C illustrate a side view, a bottom view and a front view, respectively of another embodiment of an ESU device of the present invention.

Figures 4A-4C illustrate a side view, a bottom view, and a front view, respectively of another embodiment of an ESU device of the present invention.

Figures 5A-5C illustrate a side view, a bottom view, and a front view, respectively of another embodiment of an ESU device of the present invention.

Figures 6A-6C illustrate a side view, a bottom view, and a front view, respectively of another embodiment of an ESU device of the present invention.

Figures 7A-7C illustrate a side view, a bottom view, and a front view, respectively of another embodiment of an ESU device of the present invention. Figures 8A-8C illustrate a side view, a bottom view and a front view of another embodiment of an ESU device of the present invention.

Detailed Description of the Preferred Embodiments

While the invention will be described in connection with preferred embodiments, it will be understood that it is not intended to limit the invention to those embodiments. On the contrary, the following description is intended to cover all alternatives, modifications, and equivalents as may be included within the spirit and scope of this invention as defined by the appended claims.

Turning now to the Figures, illustrated in Figure 1 is a system which incorporates an ESU device in conjunction with a primary, non- electrosurgical instrument, generally indicated at 2. The system 2 includes a primary instrument 4, for example, a powered surgical cutter or debrider. The ESU device may be used with a wide variety of non-electrosurgical devices other than a debrider. for example, a drill, a burr, a scalpel, an ultrasonic aspirator, and any other surgical instruments which result in bleeding. The debrider 4 includes a debrider tip 6 which is attached to a debrider handpiece 8. The debrider handpiece 8 is attached to a debrider control box 10. Also connected to the debrider control box 10 is a foot pedal 12 for controlling the operation of the debrider 4. In this embodiment an ESU device 14 is attached to the debrider tip 6. Extending from a proximal end of the ESU device 14 are connecting cables 16 that lead to an ESU generator 18. An exemplary ESU generator that can be used with the preferred embodiment is a Force IB, made by Valleylab, Inc. of Boulder, Colorado. Among such generators are those made by Conmed, Erbe, Everest, and Valley Forge Scientific. Also attached to the ESU generator 18 is a foot pedal 20 for controlling the operation of the ESU device 14.

Figures 2A-2C illustrate a first preferred embodiment of the present invention. As illustrated, the ESU device 14 comprises a skin or carrier 22. In this embodiment, the carrier 22 is fit over the debrider tip 6. The carrier 22 should be of a material which allows it to conform to the surface of the debrider tip 6. The carrier 22 is preferably made of a polyimide and is conformably affixed to the debrider tip 6. The carrier 22 should generally conform to the surface to which it is affixed and should minimize the amount by which it augments the cross-sectional dimensions of the primary instrument in order not to obstruct a surgeon's line of sight of the tissue being treated or interfere with the operation of the primary instrument. Furthermore, the carrier 22 should add very little extra weight to the primary instrument.

Typically the primary instrument has an operative region at its distal end. The primary instrument may include a disposable or resposable portion. If so, the operative region will be within the disposable or resposable portion. Such disposable or resposable portion will connect to a non-disposable or non-resposable portion of the primary instrument (similar to handpiece 8). The carrier 22 has a distal portion that adheres to the distal portion of the disposable or resposable portion, but will not envelop the operative region thereof. The carrier 22 also has a proximal portion that adheres to the proximal portion of the disposable or resposable portion of the primary instrument. Between the distal and proximal portions of the carrier 22 is a shank or body portion, adhering to the middle portion of the primary instrument. Typically, the shank and proximal portions of the carrier 22 will girdle the primary instrument and thus gain a sure grip to the primary instrument. A housing 24 for the debrider tip 6 is a cylindrical tube, typically terminating in a rounded distal end 26. A window 28 is cut out of the distal end tip 26 in order to provide the operative region and to allow access to tissue under consideration. At the window 28 tissue is severed by a cutting mechanism (not shown) located at the distal end of the debrider housing 24. An example of a debrider for use in the present embodiment is a Hummer 1 (SSE4 arthroscopic shaving system), made by Stryker Corporation, Kalamazoo, Michigan. Other examples of a debrider which may be used with the present invention include the Hummer 2, also made by Stryker, the Wizard and the XPS Straightshot, made by Xomed Surgical Products, Inc. (Jacksonville, Florida); the ESSential, made by Smith & Nephew (Andover, Massachusetts); and the Rhinotech, made by Linvatec Corporation (Largo, Florida). (Hummer 1 , Hummer 2, Wizard, XPS Straightshot, ESSential and Rhinotech are trademarks or trade names of their respective manufacturers.) Some debrider tips are manufactured to present a curved contour. It is also possible that in the course of the surgical procedure the debrider tips may be bent or reshaped. The debrider tip will typically include a method for aspirating the severed tissue. The carrier 22 is preferably semirigid or flexible and made of a polymeric material (e.g., polyimide, polyethylene), silicone or other plastic of similar strength, firmness and electrical resistivity. In the preferred embodiment, such material is generally targeted to be no more than 0.5 mm thick, with some special sectors, for example the areas maintaining the conductors 30a, 30b having thickness no more than 1.0 mm. Carriers of such thickness has a strength necessary to withstand the heat and abrasion encountered in surgery. Keeping the carrier to this thickness minimizes the radial augmentation thereby preserving the visibility of the surgical site. However, even with thicknesses in the special sectors up to 2.0 mm, there can still be an adequate line of sight. The carrier should be able to tolerate a temperature range of -10°C to at least 100 °C. The carrier should be able to withstand 30% to 100% relative humidity. Given that some primary instruments may be flexed or bent during the surgical procedure, the carrier 22 should be semi-rigid or malleable, similar to a flexible catheter. Furthermore, the carrier 22 should be able to insulate against power levels up to 150 watts (as may be required in bi-polar implementations) . The particular polymeric material selected should be bio-compatible and non-reflective. It should also be sterilizable by ethylene oxide (EtO) and steam autoclaving, which are in common use in the health care industry.

The carrier 22 will be as thin as possible, yet be thick enough to insulate the electrodes from leaking to the primary instrument or to the external environment excluding, of course, intended discharge at the surgical site. Where the carrier 22 directly encompasses the electrode arrangement and provides necessary insulation, it will usually be thicker than in its other sectors.

The carrier 22 preferably matches the length of the debrider tip 6. For example, the carrier 22 for use with the Hummer 1 shaver tip would be approximately 80 mm long from its hub to the distal end of the tip. When affixed, the carrier 22 will lie forward of the point where the debrider tip 6 enters the handpiece 8. The distal end of the carrier 22 will conform to the rounded shape of the distal end of the debrider tip 6. A portion of the fore end of the carrier 22 is open to correspond with and not occlude the window 28 of the debrider tip 6. The edge of the carrier 22 surrounding the window 28 may be chamfered or radiused to be smooth or it may be flat-cut. In the preferred embodiment, the cut-out measures about 11.5 mm in length and about 2.1 mm deep. This provides that the cut-out of the carrier 22 does not extend to the very perimeter of the window 28. Preferably the cut-out of the carrier 22 will be no closer than about 0.35 mm to the edge of the window 28.

The carrier 22 is firmly and permanently affixed to the debrider housing 24 by an adhesive material. The carrier 22 should be affixed to the debrider housing 24 such that no pockets are formed between the carrier 22 and the debrider housing 24 and the carrier 22 is smooth and wrinkle-less to prevent contaminants from intruding and being lodged between the debrider housing 24 and the carrier 22.

The adhesive materials used in conjunction with the carrier 22 should not be brittle or frangible. They should be able to withstand flexing or bending of the underlying instrument. Furthermore, the materials of the present invention can withstand temperatures of at least 100 degrees C, will not readily degrade and emit "outgassing" and are resterilizable under such common means as steam autoclaving or exposure to such sterilants as EtO.

The adhesion between the carrier 22 and the primary instrument should exclude blood and other contaminants from becoming lodged therebetween. Heat-shrunk means, while satisfactory for single-use devices, may permit contaminants to enter between the layers during surgery and thus preclude re-sterilization.

Still referring to Figures 2A-2C, in this embodiment two conductors 30a, 30b are imbedded in the carrier 22. Either one of the two conductors 30a, 30b conducts radio frequency current to the surgical site and the other conductor returns the current to the ESU generator 18. Each conductor may be a wire of approximately 0.63 mm (0.28 inches) diameter (23 AWG). Exemplary wires are copper, in either flat or round cross-section. The wire should be robust enough to withstand powers up to 150 watts. The wires run between a proximal end of the carrier 22 and a distal end of the carrier 22. Each conductor 30a, 30b terminates in a contact point 32a, 32b, respectively.

The electrode can be wire, cable or similar conductor of proper composition, gauge and shape. Alternatively, the electrode can be a conductive film, ring or layer placed on an insulative substrate. The electrode has at its proximal end a connector (e.g. a connecting cable with a plug) by which the conductor can be connected to an ESU generator. The distal end of a conductor has a contact point which comes in near contact or direct contact with the tissue and couples the electrical energy into the tissue, or since the mode is bipolar, from the tissue. A portion of the primary instrument can be used as a return electrode, provided that in view of such risks as leakage, capacitance and inductance, special precautions are taken to ensure that such return path is as safe as a return path provided by conductive wires or films.

At least one of the conductors delivers electrical energy to the surgical site, and at least one of the conductors is a return conductor. A gap is left between the distal ends of the conductors leading the electrical energy to the site. Electrical energy flows across the gap and, depending upon the waveform and electrical power density selected, the flow of energy may either cut, coagulate, shrink or fuse the tissue, though coagulation is the primary use foreseen for the ESU device. The size, shape and location of the distal ends of the conductors will vary according to the nature of the tissue and the nature of the surgical effect that is desired.

The conductors 30a, 30b are imbedded within a dorsal region of the carrier 22. As illustrated in Figure 2C, the portion of the dorsal wall encompassing the conductors 30a, 30b is thicker than other portions of the carrier 22. The contact points 32a, 32b emerge from the distal end of the carrier 22 generally midpoint on the slope between the fore end of the carrier 22 and the dorsal wall. The contact points 32a, 32b may be circular, rectangular or shaped pads resembling nodules or nubbins. The contact points 32a, 32b are preferably soldered to the conductor 30a, 30b, respectively. However, the contact points 32a, 32b may also be integrally joined to the conductors, clamped, welded or connected by any other well known means. If the contact points 32a, 32b are flat, they may be flush with the carrier surface or preferably will extend outward slightly from the carrier surface. The contact points 32a, 32b may also be recessed from the carrier surface. When the contact points 32a, 32b extend outward from the carrier surface, they tend to enhance the ready and precise flow of energy between the contact points 32a, 32b thereby facilitating the reduction of coagulum. If a coagulum of tissue accumulates in the region of the carrier 22 about the contact points 32a, 32b, it may be brushed or chipped off and energy may be applied to remove any remaining traces. The contact points 32a, 32b are preferably no further than approximately 3 mm from the distal end of the carrier 22 and will lie on a slope of the carrier 22 that gives them access to tissue lying in front of the carrier 22 tip and to tissue lying on a side of the debrider tip 6. The contact points 32a, 32b, preferably have a cross-sectional diameter of approximately 0.6 mm and are at a minimum approximately 0.8 mm from each other. The contact points 32a, 32b are composed of electrically conductive material which is also bio-compatible (e.g., stainless steel, gold, silver, nickel or copper). They may also be coated with a suitable conductive, yet low-friction coating.

Adjacent the proximal end of the carrier 22 is a hub 34 which supports the proximal end of the carrier 22. The proximal end of the conductors 30a, 30b are connected to the distal ends of the connecting cable 16 at the hub 34. One of the connecting cables 16 is connected to each one of the conductors 30a, 30b. The connecting cables 16 transfer energy from the ESU generator 18 to the conductors 30a, 30b. The connecting cables 16 may be up to 10 feet long. At the proximal end of the connecting cable 16 is a standard "banana" connector 36 which plugs into the ESU generator 18. The connecting cables 16 should be strong enough to withstand powers of up to 150 watts. The connecting cable 16 may be connected to the conductors 30a, 30b using conventional connection devices. Figures 3A-3C illustrate another embodiment of the present invention. Therein the carrier 22 is permanently affixed to a dorsal side of the debrider tip 6. The carrier 22 extends distally along the debrider tip 6 to a point where the debrider tip begins to form its distal rounded contour. The conductors 30a, 30b extend along the carrier 22 terminating in contacts 32a, 32b. The contacts emerge from the carrier 22 in semi-rounded contact points that are convex towards the dorsal side of the debrider tip 6. A dorsal region of the carrier 22 is chamfered, as may be necessary.

In this embodiment, the carrier 22 comprises a first layer or substratum of film or tape 36a of adhesive/insulating material which is permanently adhered to the dorsal region of the debrider tip 6. The electrode arrangement comprises the conductors 30a. 30b which are affixed to the tape 36a and extend along the tape 36a terminating in contact points 32a, 32b. The tape 36a insulates the conductors 32a, 32b from the debrider housing 24. Another layer or superstratum of film or tape 36b, is applied to, overlays, and covers the conductors 30a, 30b and is affixed to the first tape 36a. The second tape 36b insulates the conductors 30a, 30b from the external environment. The tape 36a extends slightly further in a distal direction along the debrider tip 6 than the second tape 36b. As such, the contact points 32a, 32b emerge from the carrier 22 and are exposed towards the dorsal side of the debrider tip 6. The substratum can be polymeric or ceramic coating. These materials bond well with surgical-grade stainless steel, which is commonly used for many surgical instruments.

Where the primary instrument is made of a material other than steel, it may be necessary first to apply a separate layer of adhesive material (a first substratum) for example a two-part biocompatible epoxy (e.g., Epotek ND- 353), to the primary instrument surface. Thereafter, a layer of insulative material (a second substratum) is applied to the adhesive layer. The electrode arrangement and the second layer of insulating material is applied as described above.

Depending upon which embodiment of the present invention is used in conjunction with a primary instrument, as described above, the substratum will cover significant amount of the external surface of the primary instrument The substratum will be applied more thickly where the electrode arrangement is laid onto the substratum. The superstratum will preferably cover at least area of the substratum where the electrode arrangement is laid on. and may also extend to cover the entire substratum.

Figures 4A-4C illustrate another embodiment of the present invention including ESU capability in conjunction with a non-electrosurgical device. This embodiment includes a pair of conductors 30a, 30b embedded in the carrier 22. To minimize radial augmentation, the conductors may be flat or rectangular, as opposed to round. One of the conductors 30a extends in a distal direction in the carrier 22 forming a hook portion 38 at its end. The other conductor 30b extends in a distal direction within the carrier 22 terminating at a point within the hook portion 38 of the conductor 30a. The conductor 30a includes a plurality of contacts 42a, 42b, 42c, 42d positioned about the hook portion 38, with contacts 42b and 42c on the slope and the other contacts on the dorsal sidewalk The conductor 30b terminates in a single contact point 43. All of the contact points 42a-42d, 43 are flush with the carrier 22. Figures 5A-5C illustrate another embodiment of the present invention including an ESU device in conjunction with a surgical instrument. In this embodiment, conductors 30a, 30b are embedded in the carrier 22 and extend along the carrier terminating in jutting contacts 32a, 32b. The carrier 22 extends distally along the dorsal region of the debrider tip 6 terminating at the bottom of the slope which begins to form the contoured end of the debrider tip 6. The contacts 32a, 32b extend from the carrier 22.

Figures 6A-6C illustrate another embodiment of the present invention including ESU capability in conjunction with a non-electrosurgical instrument. This embodiment includes a pair of conductors 30a, 30b which are embedded in the carrier 22. The conductors 30a, 30b flank the dorsal side of the debrider tip 6. The conductors 30a, 30b terminate at contact points 32a, 32b respectively in a mid-portion of the slope which forms the forward contour of the debrider tip 6. It is also possible and may be desirable to complement the primary instrument and ESU capability with visualization capability for image- guided surgery. Such capability may be added by means of a sensor 46 at the distal end of the primary instrument, so that it can provide visibility of the location of the primary instrument and the ESU adjunct. Like the contact points 32a, 32b, the sensor 46 may be protected from surgical rigors by the carrier 22, and its connection to a control device may run parallel with the ESU conductors 30a, 30b. Exemplary sensing devices are manufactured by Biosense, Inc. (Tel Aviv, Israel) and Visualization Technology, Inc. (Woburn, MA).

Figures 7A-7C illustrate another embodiment of the present invention. This embodiment includes a pair of conductors 30a, 30b which are embedded in the carrier 22. The conductors 30a, 30b extend along the dorsal side of the debrider tip in a distal direction up along the contour of the forward portion of the debrider tip 6 terminating in contact points 32a, 32b at the forward end of the debrider tip. The contacts 32a, 32b are slightly tilted towards each other and extend slightly from the surface of the carrier 22. In yet another embodiment of the present invention, shallow grooves may be formed in the external surface of the primary instrument to accommodate the conductors and their necessary insulation. Such an arrangement improves the line of sight for the surgeon and reduces the bulk of the instrument. To further improve the line of sight, deep grooves may be etched into the primary instrument which may receive the full thickness of the conductors 30a, 30b and necessary insulation. The grooves should not be so deep as to communicate with the inside of the tubing of the primary instrument.

In still another embodiment, a slit that communicates with the inside of the outer tubing of the primary instrument is cut in the primary device. Figures 8A-8C illustrate a side view, a bottom view and front view of a primary instrument having an outer tube housing 24 into which a slit 60 has been cut into the dorsal side of the shank portion. The slit 60 is just wide enough to accommodate the two conductors 30a, 30b. The conductors 30a, 30b are packed into the slit 60 such that they do not impinge into the interior of the outer tube 24 or the interior of the debrider tip 6. The conductors 30a, 30b will not interfere with any internal elements within the tube 24. A biocompatible epoxy- base adhesive (not shown) is used to fix the conductors 30a, 30b in the slit 60. Suitable adhesives are available that will provide as much strength to the tubular housing as the basic material of the housing provides. For example, Epotek ND- 353 or Master Bond EP42HT can be used for this purpose.

The conductors 30a, 30b pass from the proximal hub 34, into the slit 60. In this embodiment, the conductors 30a, 30b extend along the tip 6 and terminate in splayed contact points 32a, 32b located in the distal portion of the tip 6. A layer of insulating material may be attached to the tip 6 between the contact points 32a, 32b and the housing 24. This insulation prevents any inadvertent discharge between the contacts 32a, 32b and the housing 24. By integrating the ESU capability into the primary instrument by means of the slit 60, the primary instrument has minimal augmentation and maintains its essential structure. In other surgical procedures, magnetic resonance imaging ("MRI") is used to guide the surgeon in other surgical procedures, especially in neurosurgery (e.g. open MRI). However, when MRI is used, the surgical instruments should have minimal distortion or interference on the magnetic field. Stainless steel, for example, can have excessive interference. On the other hand, titanium can be used with MRI without significantly impairing the magnetic field . For such procedures, the primary instrument should therefore be made of non- distortive materials, such as titanium, and the conductors and contact points of the ESU device should likewise mae use of non-distortive materials. Polymeric materials used for the carrier do not interfere with the magnetic field. A preferred embodiment of the present invention is used in the following manner. The carrier 22 will have been packaged in sterile condition. The carrier 22 is opened in the sterile field and attached to the debrider tip 6 before surgery.

In the usual case, the debrider tip 6 will sever some blood vessels in the course of surgery through the cutting mechanism in the window 28. The surgeon will identify where the vessel in question has been severed and will bring the window (ventral) side of the debrider tip 6 to the vessel.

Then the surgeon will rotate the debrider tip 6 and carrier 22 to a position such that the contact points 30a, 30b are apposed to the portion of the vessel that is to be coagulated and stanched. In a preferred embodiment, the contact points 30a, 30b jut out slightly from the distal end of the carrier 22. The contact points 30a, 30b are then gently pushed against the tissue, causing the tissue of interest to lie between the jutting contact points 30a, 30b. The electrical energy is then released at the appropriate power. The bleeding should stop promptly. The same process may be repeated as necessary for several bleeders.

By forming the surgical defect in this bipolar manner the system benefits from the path of the energy being direct from a first point to a second point, with less detour and therefore less collateral tissue damage, both in depth and in breadth. Tissue may be cut in the above manner, with variations in the power and waveform. Furthermore, the device may be applied to tissue before the debrider removes the tissue. In this manner, the flow of blood may be anticipated and prevented. The device may also be used to remove tags of tissue and seal up any remaining bleeders. After the procedure has been completed, the connecting cables 16 are detached from the electrode arrangement and the debrider tip 6 and the carrier 22 can be re-sterilized.

The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and, accordingly, reference should be made to the appended claims, rather than to the foregoing specification, as indicating the scope of the invention.

Claims

1. A bipolar electrosurgical device for use in conjunction with a non-electrosurgical instrument, comprising: an electrode arrangement having a first end for connection to an electrosurgical generator and a second end, remote from the first end, for engaging tissue to be electrosurgically treated, and a carrier for supporting and permanently affixing the electrode arrangement to the non-electrosurgical instrument, the whole device adapted to provide selective coagulation in endoscopic surgery.

2. A device as set forth in claim 1, wherein the carrier is affixed to the non-electrosurgical instrument at a location adjacent an operative region thereof such that the second end of the electrode arrangement is in close proximity to tissue being operated on by the non-electrosurgical instrument.

3. A device as set forth in claim 1 , wherein the electrode arrangement comprises two electrical conductors extending between the first end and the second end, each conductor terminating at the second end in at least one contact element.

4. A device as set forth in claim 1, wherein the carrier includes an adhesive element which affixes it to the non-electrosurgical instrument.

5. A device as set forth in claim 1, wherein the electrode arrangement comprises a plurality of electrodes.

6. A surgical instrument combining bipolar electrosurgical capability and non-electrosurgical capability, comprising: a generally cylindrical housing having a distal end and a proximal end; a non-electrosurgical operative element positioned at the housing distal end; a bipolar electrosurgical element comprising a pair of conductors traversing the length of the housing, integrated with the housing, each of the conductors terminating at the housing distal end in a contact element.

7. A device as set forth in claim 6, wherein the contact elements are splayed from each other at the distal end.

8. A device as set forth in claim 7, further comprising a layer of insulating material on positioned on the distal end of the housing separating the housing distal end from the contact elements.

9. A device as set forth in claim 6, wherein the contact elements are flush with the housing distal end.

10. A device as set forth in claim 6, wherein the contact elements jut out from the housing distal end.

11. A surgical method by which electrosurgical energy may be used conjunctively with other surgical apparatus in the same surgical intervention, the method comprising the steps of: cutting tissue apposed to the operative region of such other surgical apparatus, thereby causing said tissue to bleed; rotating the surgical apparatus on its longitudinal axis such that an operative region of an affixed electrosurgical element is apposed and aligned with the cut and bleeding tissue; gently pushing the operative region of the affixed electrosurgical element into said tissue, such that said tissue lies between electrosurgical contact points jutting from the electrosurgical element; and causing electrical energy to be discharged between the contact points, thereby stanching the flow of blood.