Abstract:
The present disclosure is directed to electrosurgical pencils having variable controls. In one aspect, the electrosurgical pencil, includes an elongated housing, an electrocautery blade supported within the housing and extending distally from the housing, the electrocautery blade being connected to a source of electrosurgical energy, an activation button supported on the housing, the activation button being movable from a first position to at least a subsequent position, and a transducer electrically connected between the activation button and the source of electrosurgical energy. The transducer is configured to transmit an electrical output signal to the electrosurgical energy source correlating to the movement of the activation button. The source of electrosurgical energy correspondingly supplies an amount of electrosurgical energy to the electrocautery blade dependant upon the electrical output signal.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   The present application claims the benefit of and priority to U.S. Provisional Application Ser. No. 60/424,352 filed on Nov. 5, 2002, the entire contents of which are incorporated herein by reference. 

   BACKGROUND 
   1. Technical Field 
   The present disclosure relates generally to electrosurgical instruments and, more particularly, to an electrosurgical pencil having a single button variable control. 
   2. Background of Related Art 
   Electrosurgical instruments have become widely used by surgeons in recent years. Accordingly, a need has developed for equipment and instruments which are easy to handle, are reliable and are safe in an operating environment. By and large, most electrosurgical instruments typically include a hand-held instrument, or pencil, which transfers radio-frequency (RF) electrical energy to a tissue site. The electrosurgical energy is returned to the electrosurgical source via a return electrode pad positioned under a patient (i.e., a monopolar system configuration) or a smaller return electrode positionable in bodily contact with or immediately adjacent to the surgical site (i.e., a bipolar system configuration). The waveforms produced by the RF source yield a predetermined electrosurgical effect known generally as electrosurgical fulguration. 
   In particular, electrosurgical fulguration includes the application of electric spark to biological tissue, for example, human flesh or the tissue of internal organs, without significant cutting. The spark is produced by bursts of radio-frequency electrical energy generated from an appropriate electrosurgical generator. Generally, fulguration is used to either coagulate, cut or seal body tissue. Coagulation is defined as a process of desiccating tissue wherein the tissue cells are ruptured and dehydrated/dried. Electrosurgical cutting, on the other hand, includes applying an electrical spark to tissue in order to produce a cutting effect. Meanwhile, sealing is defined as the process of liquefying the collagen in the tissue so that it forms into a fused mass. 
   As used herein the term “electrosurgical pencil” is intended to include instruments which have a handpiece which is attached to an active electrode and which is used to coagulate, cut and/or seal tissue. Typically, the electrosurgical pencil may be operated by a handswitch or a foot switch. The active electrode is an electrically conducting element which is usually elongated and may be in the form of a thin flat blade with a pointed or rounded distal end. Alternatively, the active electrode may include an elongated narrow cylindrical needle which is solid or hollow with a flat, rounded, pointed or slanted distal end. Typically electrodes of this sort are known in the art as “blade”, “loop” or “snare”, “needle” or “ball” electrodes. 
   As mentioned above, the handpiece of the electrosurgical pencil is connected to a suitable electrosurgical energy source (i.e., generator) which produces the radio-frequency electrical energy necessary for the operation of the electrosurgical pencil. In general, when an operation is performed on a patient with an electrosurgical pencil, electrical energy from the electrosurgical generator is conducted through the active electrode to the tissue at the site of the operation and then through the patient to a return electrode. The return electrode is typically placed at a convenient place on the patient&#39;s body and is attached to the generator by a conductive material. 
   Current electrosurgical instrument systems allow the surgeon to change between two pre-configured settings (i.e., coagulation and cutting) via two discrete buttons disposed on the electrosurgical pencil itself. Other electrosurgical instrument systems allow the surgeon to increment the power applied when the coagulating or cutting button of the instrument is depressed by adjusting or closing a switch on the electrosurgical generator. The surgeon then needs to visually verify the change in the power being applied by looking at various displays and/or meters on the electrosurgical generator. In other words, all of the adjustments to the electrosurgical instrument and parameters being monitored during the use of the electrosurgical instrument are typically located on the electrosurgical generator. As such, the surgeon must continually visually monitor the electrosurgical generator during the surgical procedure. 
   Accordingly, the need exists for electrosurgical instruments which do not require the surgeon to continually monitor the electrosurgical generator during the surgical procedure. In addition, the need exists for electrosurgical instruments whose power output can be adjusted without the surgeon having to turn his vision away from the operating site and toward the electrosurgical generator. 
   SUMMARY 
   The present disclosure is directed to an electrosurgical instrument having variable controls. In accordance with one aspect of the present disclosure the electrosurgical instrument, includes an elongated housing, an electrocautery blade supported within the housing and extending distally from the housing, the electrocautery blade being connected to a source of electrosurgical energy, an activation button supported on the housing, the activation button being movable from a first position to at least a subsequent position, and a transducer electrically connected between the activation button and the source of electrosurgical energy. The transducer is configured to transmit an electrical output signal to the electrosurgical energy source correlating to the movement of the activation button. The source of electrosurgical energy correspondingly supplies an amount of electrosurgical energy to the electrocautery blade dependant upon the electrical output signal. 
   In one aspect, the activation button is depressed to initiate transmission of the electrical output signal. Preferably, the activation button is movable from a first position to a series of discrete, subsequent positions wherein each subsequent position corresponds to a specific amount of electrosurgical energy being transmitted to the electrocautery blade. 
   It is envisioned that the transducer is a pressure-sensitive transducer. Preferably, the pressure transducer produces at least two output signals based upon the movement of the activation button. It is further envisioned that one of the at least two signals of the pressure transducer transmits a signal to the electrosurgical generator corresponding to the emission of energy having a cutting-type waveform and the other of the at least two signals of the pressure transducer transmits a signal to the electrosurgical generator corresponding to the emission of energy having a coagulating-type waveform. 
   Preferably, the pressure transducer transmits a range of output signals to the source of electrosurgical energy in response to the position of the activation button. The range of output signals corresponds to a range of energy emission from the source of electrosurgical energy to the electrocautery blade. 
   In a further aspect, the activation button includes a slide-switch which is slidingly supported on the housing and is configured for selective movement along a slide path formed in the housing. The transducer is configured to produce an output signal to the source of electrosurgical energy which corresponds to the movement of the slide-switch within the slide path of the housing. 
   Preferably, the slide-switch transmits a range of output signals to the source of electrosurgical energy in response to the position of the slides-witch, the range of output signals varying from when the slide-switch is at a proximal-most position to when the slide switch is at a distal-most position. The slide-switch is configured and adapted to be depressed to initiate movement thereof and activation of the electrocautery blade. 
   In another aspect of the present disclosure, the electrosurgical pencil further includes a control pendent operatively coupled to the housing and electrically connected to the source of electrosurgical energy. The control pendent includes at least one control knob operatively supported thereon, wherein the at least one control knob is configured and adapted to enable selection of a particular emission signal from the electrosurgical generator. 
   Preferably, the at least one control knob is electrically connected to the activation button. It is envisioned that the at least one control knob is electrically connected to the source of electrosurgical energy. 
   It is contemplated that the control pendent is configured and adapted to be removably attached to at least one of a user&#39;s wrist, user&#39;s garment and operating table. It is further contemplated that the control pendent includes at least one knob for selecting a function of the electrosurgical instrument and at least one other knob for selecting a power output of the source of electrosurgical energy. 
   These and other objects will be more clearly illustrated below by the description of the drawings and the detailed description of the preferred embodiments. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, and together with a general description of the invention given above, and the detailed description of the embodiments given below, serve to explain the principles of the invention. 
       FIG. 1  is a partially broken, side elevational view of one embodiment of an electrosurgical pencil in accordance with the present disclosure; 
       FIG. 2  is a partially broken, side elevational view of an alternate embodiment of the electrosurgical pencil, in accordance with the present disclosure, shown in a first position; 
       FIG. 3  is a partially broken, side elevational view of the electrosurgical pencil of  FIG. 2  shown in a second position; and 
       FIG. 4  is a perspective view of another alternate embodiment of an electrosurgical pencil shown being held in the hand of a surgeon (shown in phantom). 
   

   DETAILED DESCRIPTION 
   Embodiments of the presently-disclosed electrosurgical pencil will now be described in detail with reference to the drawing figures wherein like reference numerals identify similar or identical elements. In the drawings, and in the description which follows, the term “proximal”, as is traditional, will refer to the end of the electrosurgical pencil which is closest to the operator, while the term “distal” will refer to the end of the electrosurgical pencil which is furthest from the operator. 
     FIG. 1  sets forth a partially broken, side elevational view of an electrosurgical pencil constructed in accordance with one embodiment of the present disclosure and generally referenced by numeral  100 . While the following description will be directed towards electrosurgical pencils it is envisioned that the features and concepts of the present disclosure can be applied to any electrosurgical type instrument. Electrosurgical pencil  100  includes an elongated housing  102  configured and adapted to support a blade receptacle  104  at a distal end thereof which, in turn, receives a replaceable electrocautery blade  106  therein. A distal end portion  108  of blade  106  extends distally from receptacle  104  while a proximal end portion  110  of blade  106  is retained within the distal end of housing  102 . Preferably, electrocautery blade  106  is fabricated from a conductive type material, i.e., stainless steel or is coated with an electrically conductive material. 
   As shown, electrosurgical pencil  100  is coupled to a conventional electrosurgical generator “G” via a cable  112 . Cable  112  includes a transmission wire  114  which electrically interconnects the electrosurgical generator “G” with the proximal end portion  110  of blade  106 . Cable  112  further includes a control loop  116  which electrically interconnects an activation button  124 , supported on an outer surface  107  of the housing  102 , with the electrosurgical generator “G”. 
   By way of example only, electrosurgical generator “G” may be any one of the following, or equivalents thereof: the “FORCE FX”, “FORCE 2” or “FORCE 4” generators manufactured by Valleylab, Inc. a division of Tyco Healthcare, LP, Boulder, Colo. Preferably, the electrosurgical generator “G” can be variable in order to provide appropriate first RF signals (e.g., 1 to 120 watts) for tissue cutting and appropriate second RF signals (e.g., 1 to 300 watts) for tissue coagulation. Preferably, an exemplary electrosurgical generator “G” is disclosed in commonly assigned U.S. Pat. No. 6,068,627 to Orszulak, et al., the entire content of which are hereby incorporated by reference. The electrosurgical generator disclosed in the &#39;627 patent includes, inter alia, an identifying circuit and a switch therein. In general, the identifying circuit is responsive to information received from a generator and transmits a verification signal back to the generator. Meanwhile, the switch is connected to the identifying circuit and is responsive to signaling received from the identifying circuit. 
   Turning back to  FIG. 1 , as mentioned above, electrosurgical pencil  100  includes activation button  124  which is supported on an outer surface  107  of housing  102 . Activation button  124  is operatively connected to a pressure transducer  126  (or other variable power switch) which, in turn, controls the RF electrical energy supplied from generator “G” to electrosurgical blade  106 . More particularly, pressure transducer  126  electrically couples to control loop  116  and is configured to regulate (or variably control) the amount of RF energy transmitted to electrocautery blade  106  and/or to variably control the waveform output from electrosurgical generator “G”. 
   In use, pressure transducer  126  converts input energy of one form into output energy of another. For example, pressure transducer  126  initially converts a pressure input from activation button into an output signal which is transmitted to electrosurgical generator “G”. In turn, generator “G” transmits a corresponding amount of energy (or an appropriate waveform output) to electrocautery blade  106  via transmission wire  114 . As such, by selectively applying pressure to switch  124  to apply pressure to pressure transducer  126 , the surgeon can variably control the amount of energy and/or the waveform output of the electrosurgical generator “G”. For example, by applying a relatively light pressure against activation button  124 , and, in turn, to pressure transducer  126 , in the direction of arrow “P” in  FIG. 1 , thus depressing pressure transducer  126  a relatively small amount, a “cutting-type” waveform is transmitted. By applying a relatively heavy pressure against activation button  124 , thus depressing pressure transducer  126  a relatively large amount, a “coagulating-type” waveform is transmitted. As can be appreciated, an intermediate pressure applied against activation button  124  will produce varying combinations of “cutting-type” waveforms and “coagulating-type” waveforms. 
   More particularly and in use, when activation button  124  is depressed in direction “P”, pressure is applied against transducer  126  which, in turn, converts the input pressure into a corresponding electrical signal. The electrical signal is transmitted, via control loop  116 , to electrosurgical generator “G”. Electrosurgical generator “G”, in turn, processes the electrical signal received from pressure transducer  126  and transmits an output signal (i.e., RF energy, waveform, power, voltage, current, duty, cycle, frequency and the like), via transmission wire  114 , to electrocautery blade  106 . As can be appreciated, the pressure “P” applied to activation button  124  against the pressure transducer  126 , directly determines the overall level of output of electrosurgical generator “G” and, in turn, the ultimate function of electrocautery blade  106 . Since activation button  124  can be depressed to a variety of positions the surgeon is able to create a pallet of varying therapeutic effects ranging from a pure “cutting” mode to a pure “coagulating” mode and variations therebetween. It is envisioned that the switch  124  may include a plurality of incremental steps (not shown) to provide better tactile feedback to the surgeon. It is also contemplated that the incremental steps may include audible feedback to further enhance the surgeon&#39;s tactile feedback. 
   As such, the surgeon need not visually verify the new setting of electrosurgical pencil  100  by continuously checking the display, meters or gauges on electrosurgical generator “G”. In particular, the surgeon will be able to make changes to the electrosurgical pencil, as needed, from the operative field. 
   It is contemplated that activation button  124  can included other electromechanical sensors, e.g., optical sensors, pneumatic sensors, accelerometer, position sensors, etc. to provide sensory feedback to generator “G”. As mentioned above, the activation button  124  may also include some measure of tactile feedback which is felt by the surgeon&#39;s finger and/or some measure of audible feedback produced by the activation button  124  (e.g., a “click”), by the electrosurgical generator “G” (e.g., a “tone”) and/or an auxiliary sound-producing device such as a buzzer (not shown). 
   While RF energy and waveforms have been disclosed as being controlled by the position of or pressure applied to pressure transducer  126 , it is envisioned that other electrosurgical parameters can be controlled by pressure transducer  126 , such as, for example, power, voltage, current, duty, cycle and/or frequency. 
   Turning now to  FIGS. 2–3 , an alternate electrosurgical pencil  200  is shown and includes a slide-switch  224  which is slidably supported atop a slide bed  228  disposed within the outer surface  107  of housing  102 . Preferably, slides-witch  224  is operatively connected to transducer  226  which is, in turn, electrically connected to control loop  116  in a similar manner as described above. 
   In the present embodiment, as slide-switch  224  is displaced, either proximally or distally along activation line “X”, transducer  226  converts the degree of displacement of slide-switch  224  into a signal which is transmitted to electrosurgical generator “G” via transmission line  116 . Generator “G”, in turn, transmits a corresponding amount of RF energy (or an appropriate waveform output) to electrocautery blade  106 . As such, slide-switch  224 , in combination with transducer  226 , allows the surgeon to variably control the amount of energy and/or the waveform output of electrosurgical generator “G”. For example, when slide-switch  224  is in a proximal-most position, as seen in  FIG. 2 , a “cutting-type” waveform is selected. Meanwhile, by displacing slide-switch  224  to a distal-most position, as seen in  FIG. 3 , a “coagulating-type” waveform is selected. It is envisioned that positioning slide-switch  224  at discrete locations along the length of slide bed  228  will induce a combination of “cutting-type” waveforms and “coagulating-type” waveforms. Accordingly, the surgeon can select the therapeutic effect desired by simply displacing slide-switch  224  to an appropriate position along slide bed  228 . 
   It is envisioned that slide bed  228  may be configured such that slide-switch  224  “clicks” into discrete positions along slide bed  228  from the proximal-most position to the distal-most position. The “clicking” provides the surgeon with both tactile and audible feedback as to the location of slide-switch  224 . It is further envisioned that electrosurgical pencil  200  may be activated and deactivated (i.e., energized or de-energized) by depressing and then releasing sliding button  224 . 
   Turning now to  FIG. 4 , an alternate embodiment of an electrosurgical pencil  300  is shown and includes at least one activation button  324  supported on the outer surface  107  of housing  102 . It is envisioned that two activation button  324 ,  325  may also be employed. In accordance with this embodiment, electrosurgical pencil  300  preferably includes a pendent  350  which is configured and adapted to be removably attached to or stuck to the surgeons wrist or coat sleeve “C” (as seen in  FIG. 4 ), the patients drapes or robe, or a Mayo stand. It is envisioned that the pendent  350  may also be removably attached by any known means such as clips, Velcro™, band, belt, elastic, or the like. 
   As seen in  FIG. 4 , pendent  350  is electrically connected to electrosurgical pencil  300  via a connecting wire  352 . Optionally, pendent  350  can be electrically connected to electrosurgical generator “G” via a connecting wire  354  (shown in phantom in  FIG. 4 ). Pendent  350  preferably includes at least some of, if not all of, the variable controls  356  of electrosurgical pencil  300 . Variable controls  356  permit the surgeon to select the function desired (i.e., cutting or coagulating) and to vary the power being supplied by electrosurgical generator “G” to electrosurgical pencil  300 . Variable controls  356 , include, but are not limited to knobs, buttons, switches, dials, slides, touch screens, etc. 
   In use, the surgeon can select the function and level of power from pendent  350  instead of electrosurgical generator “G”. The surgeon then uses or activates and deactivates electrosurgical pencil  300  in a conventional manner by depressing and releasing activation button  324  or  325 . Accordingly, during use of electrosurgical pencil  300 , if the surgeon desires to vary or adjust the output or function of electrosurgical pencil  300 , the surgeon simply needs to adjust variable controls  356  of pendent  350 . As such, the surgeon does not need to adjust the controls of the electrosurgical generator “G” or take his/her focus and/or attention away from the patient and the surgical procedure being performed. In addition, in combination or alternatively, a status monitor may also be employed to provide visual and audible indications corresponding to the operational status of the generator “G”. For example, one such status monitor is described in commonly owned U.S. Pat. No. 6,402,741 entitled “CURRENT AND STATUS MONITOR”, the entire contents of which are hereby incorporated by reference herein. 
   While embodiments of electrosurgical instruments according to the present disclosure have been described herein it is not intended that the disclosure be limited there and the above description should be construed as merely exemplifications of preferred embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the present disclosure.