Abstract:
The present disclosure relates to a method for performing electrosurgery. The disclosed method includes providing a wireless, bite-activated switch configured for use within a surgeon&#39;s mouth. The disclosed switch includes an activator, a transponder, and an antenna. The switch communicates with an electrosurgical energy source, such as without limitation, an electrosurgical RF or microwave generator, to convey the state of the switch and activate the generator. The disclosed method provides providing the wireless switch with a unique identifier and associating the generator with the unique switch to ensure only the intended switch can control the electrosurgical generator.

Description:
BACKGROUND 
       [0001]    1. Technical Field 
         [0002]    The present disclosure relates to electrosurgical systems and more particularly, a wireless bite-activated control device for controlling electrosurgical generators, electrosurgical instruments, and systems related thereto. 
         [0003]    2. Background of Related Art 
         [0004]    Minimally invasive surgical techniques have been developed wherein the surgical site is accessed by instruments inserted through small incisions in the body, as compared to traditional open surgical procedures where much larger incisions are required to expose the surgical site. Minimally invasive surgical procedures, also known generally as laparoscopic or endoscopic procedures, are often performed in conjunction with electrosurgical techniques. Throughout the present disclosure, the term “minimally invasive” should be understood to encompass both endoscopic and laparoscopic procedures, and the terms “minimally invasive”, “endoscopic”, and “laparoscopic” are to be construed equivalently. Minimally invasive surgical procedures are performed through access devices such as a cannula that is inserted percutaneously into a patient&#39;s body. The cannula has a central opening through which surgical objects are introduced and manipulated during the course of the procedure. 
         [0005]    Electrosurgical techniques employ radiofrequency (RF) electrical signals in the approximately 200 kHz-3.3 mHz range in connection with surgical instruments, to cut, ablate, or coagulate biologic tissue endogenically. Typically, electrosurgical signals are operated at 100% duty cycle for maximal cutting effect, and are pulse modulated at duty cycles ranging from 50% to 25% for less aggressive cutting, also referred to as blending, or, at a substantially lower duty cycle of approximately 6%, for coagulating. The electrosurgical signal can be applied to the patient via electrodes in either bipolar mode, or monopolar mode. In bipolar mode, both the active and return electrodes are at the surgical site, effectuated by, for example, both jaws of a pair of forceps, such that the electrosurgical signal passes through only the tissue that is held between the jaws of the instrument. In monopolar mode, the active electrode is the surgical instrument at the surgical site, and the return electrode is elsewhere on the patient, such that the electrosurgical signal passes through the patient&#39;s body from the surgical site to the return electrode. 
         [0006]    Typically, the instrument has at a distal end thereof an end effector, such as a blade, forceps, snare, loop, or suction coagulator, that is positioned at the surgical site. The proximal end of the instrument is coupled to a source of electrosurgical energy, such as an electrosurgical generator. After the instrument is positioned, the surgeon actuates a control, typically a handswitch on the instrument, or a footswitch, which causes electrosurgical energy to be applied through the end effector to the operative site to tissue to achieve a desired result, e.g., cutting, coagulating, ablation, or fusion. Often, requirements of a surgical procedure dictate that a surgeon manipulate one or more instruments using both hands. 
       SUMMARY 
       [0007]    The present disclosure provides a wireless switch having a resilient housing for actuation by a user, such as a surgeon, during for example, an electrosurgical procedure. The disclosed switch may be bite-activated. The switch includes an activator, such as without limitation, a pushbutton, disposed within the housing and activatable in response to a compressive force applied to at least one of the top surface and the bottom surface, e.g., in response to biting force. The disclosed switch further includes an antenna configured to at least one of transmit and receive a radiofrequency signal. The antenna may be adapted to connect to a transponder included within the switch that is configured to receive a radiofrequency interrogatory signal. In response to the radiofrequency interrogatory signal the transponder senses the state of the activator (e.g., whether the activator is activated/pressed or deactivated/released) and transmits a radiofrequency response signal conveying the state of the activator to an electrosurgical energy source, 
         [0008]    In embodiments, the activator may include conductive resilient material, such as without limitation electrically-conductive silicone. In embodiments, the activator may include a snap dome switch, membrane switch, pushbutton switch, or other suitable switch. 
         [0009]    In another aspect, an electrosurgical system is provided that includes an electrosurgical system unit. The electrosurgical system unit includes an interrogator adapted to communicate with a bite-activated wireless switch as described herein. In use, the interrogator transmits a radiofrequency interrogatory signal to the transponder included in the bite-activated switch. The transponder responds by sensing the state of the activator included within the wireless switch assembly (e.g., whether the surgeon is biting down on the switch) and transmitting a signal to the interrogator conveying the switch state. The electrosurgical system unit may include a controller, which may include a processor, for performing a set of executable instructions for performing, at least in part, a method of electrosurgery using a wireless bite-activated switch as disclosed herein. The electrosurgical system unit further includes an electrosurgical instrument coupled to an electrosurgical generator configured to selectively provide electrosurgical energy thereto, and a user interface, such as without limitation, input controls and output indicators, to facilitate interaction with the user e.g., the surgeon. 
         [0010]    In yet another aspect, the present disclosure provides a method for performing electrosurgery. The disclosed method includes the steps of providing a bite-activated wireless switch as disclosed herein, providing an electrosurgical system unit as disclosed herein causing to be transmitted an interrogatory signal to a transponder included within the bite-activated wireless switch, receiving the interrogatory signal at the transponder, causing to be transmitted in response the interrogatory signal a response signal conveying the state of the pushbutton; receiving the response signal at the electrosurgical system unit, activating the electrosurgical generator in response to a response signal conveying an actuated pushbutton state, and deactivating the electrosurgical generator in response to a response signal conveying a de-actuated pushbutton state. 
         [0011]    The present disclosure further provides a method of activating the source of electrosurgical energy wherein a first activation of a wireless switch activates the electrosurgical generator and a second activation of a wireless switch deactivates the electrosurgical generator (e.g., a push-on/push-off mode of operation). In another embodiment, a single activation of the wireless switch causes the electrosurgical generator to be activated for a predetermined period of time, after which the electrosurgical generator automatically is deactivated. Other embodiments are contemplated wherein the electrosurgical generator is deactivated if the wireless switch is activated before the fixed period of activation time elapses. In this embodiment, the disclosed system operates in a primarily push-on/push-off mode with a safety timeout feature. 
         [0012]    In still another aspect, the present disclosure provides a method of associating a bite-activated wireless switch with an electrosurgical system unit that includes the steps of providing a unique identifier for the bite-activated switch, transmitting in response to an interrogatory signal a response signal conveying the unique identifier of the bite-activated switch to the electrosurgical system unit, storing the unique identifier of the bite-activated switch, comparing the stored unique identifier to a unique identifier conveyed in a subsequent response signal, and ignoring a subsequent response signal if the unique identifier thereof differs from the stored unique identifier. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    The above and other aspects, features, and advantages of the present disclosure will become more apparent in light of the following detailed description when taken in conjunction with the accompanying drawings wherein: 
           [0014]      FIG. 1  is a schematic view of an embodiment of a wireless bite-activated switch in accordance with the present disclosure; 
           [0015]      FIG. 2A  is a top, side view of an embodiment of a wireless bite-activated switch in accordance with the present disclosure; 
           [0016]      FIG. 2B  is a front, side view of an embodiment of a wireless bite-activated switch in accordance with the present disclosure; 
           [0017]      FIG. 2C  is a right, side view of an embodiment of a wireless bite-activated switch in accordance with the present disclosure; 
           [0018]      FIG. 2D  is a perspective view of an embodiment of a wireless bite-activated switch in accordance with the present disclosure; 
           [0019]      FIG. 3A  is a top, cutaway view of an embodiment of a wireless bite-activated switch in accordance with the present disclosure; 
           [0020]      FIG. 3B  is a front, cutaway view of an embodiment of a wireless bite-activated switch in a quiescent state in accordance with the present disclosure; 
           [0021]      FIG. 3C  is a front, cutaway view of an embodiment of a wireless bite-activated switch in an activated state in accordance with the present disclosure; 
           [0022]      FIG. 4  is a schematic view of an electrosurgical system having an embodiment of a wireless bite-activated switch in accordance with the present disclosure; 
           [0023]      FIG. 5A  is a perspective view of yet another embodiment of a wireless bite-activated switch in accordance with the present disclosure; and 
           [0024]      FIG. 5B  is a perspective view of still another embodiment of a wireless bite-activated switch in accordance with the present disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0025]    Particular embodiments of the present disclosure will be described hereinbelow with reference to the accompanying drawings; however, it is to be understood that the disclosed embodiments are merely exemplary of the disclosure, which may be embodied in various forms. Well-known functions or constructions are not described in detail to avoid obscuring the present disclosure in unnecessary detail. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present disclosure in virtually any appropriately detailed structure. 
         [0026]    In the drawings and in the descriptions that follow, the term “proximal,” as is traditional, shall refer to the end of the instrument that is closer to the user, while the tern “distal” shall refer to the end that is farther from the user. 
         [0027]    With reference to  FIG. 1  and  FIGS. 2A-2D , a bite-activated wireless switch  110  is held between the teeth T of a surgeon S. Wireless switch  110  includes a housing  112  having an upper cover  125  and a lower cover  126 . In some embodiments, housing  112  has a generally pillow-like rectangular shape having radiused corners  115  as best illustrated in  FIG. 2A . The present disclosure also contemplates that housing  112  may be any shape, including without limitation circular, oval, and crescent-shaped. In embodiments, housing  112  is formed from a resilient or elastomeric material, such as without limitation, vinyl, rubber, silicone, thermoplastic elastomer (e.g., C-Flex®), polyurethane, or polypropylene. Housing  112  may be formed from biocompatible material suitable for use within the mouth and/or capable of uncompromised passage through a digestive tract in the event the wireless switch  110  is ingested. 
         [0028]    In embodiments, upper cover  125  and lower cover  126  are joined at the respective perimeters thereof by seam  120 , which may be formed by any suitable maimer of bonding, e.g., heat welding, ultrasonic welding, chemical welding, adhesive, and the like. In embodiments, upper cover  125  and lower cover  126  may be formed integrally. In embodiments upper cover  125  and/or lower cover  126  may have a textured surface (not explicitly shown) adapted to facilitate placement and retention of wireless switch  110  within the mouth and/or jaw of the user. In embodiments, the textured surface may be contoured to engage at least one of the user&#39;s teeth. Wireless switch  110  may be reusable, disposable, or partially disposable. In embodiments, the housing  112  is flavored, e.g., mint-flavored, chocolate-flavored, fruit-flavored, and so forth. 
         [0029]    With reference now to  FIGS. 3A and 3B , wireless switch  110  includes a support member  140  disposed within the housing  112 . In embodiments, support member  140  may be a circuit board constructed of any suitable material, for example without limitation, phenolic cotton paper (e.g., FR-2), cotton paper and epoxy (e.g., FR-3, CEM-1, CEM-2), woven glass and epoxy (e.g., FR-4, FR-5, G-10, CEM-3, CEM-4), matte glass and polyester (FR-6), or woven glass and polyester (CEM-5). 
         [0030]    Support member  140  includes transponder  160  that is operably coupled to antenna  165  and contacts  150 . In embodiments, transponder  160  may be an integrated circuit, such as without limitation, an RFID tag. Advantageously, transponder  160  may be a passive RFID tag that is powered by the electrical current induced in antenna  165  by the radiofrequency interrogation signal. Transponder  160  may contain read-only data, such as without limitation, a unique identifier, a model number, a compatibility identifier, and/or an expiration date. Such read-only data may be stored in an encrypted format. In embodiments, transponder  160  is operably coupled to contacts  150  by conductors  152 . Contacts  150  are in operable communication with pushbutton  170  to communicate the activation state of pushbutton  170  to transponder  160 . Pushbutton  170  may be a momentary contact switch, or a toggle contact switch (e.g., push on/push off). In embodiments, pushbutton  170  is formed from resilient conductive material, such as without limitation graphite-impregnated silicone that is adapted to cause, in response to compressive force applied to pushbutton  170 , and/or top surface  171  of pushbutton  170 , a change in resistance, e.g., a decrease in resistance, in a conductive path formed by contacts  150  and pushbutton  170 . In embodiments, pushbutton  170  is configured to provide tactile feedback to the user, for example without limitation, a clicking, snapping, or vibratory sensation. Wireless switch  110  may include a resilient member  175  configured to act as a counterpart to pushbutton  170  and provide a generally equal distribution of bite forces imposed on housing  125  and/or wireless switch  110 . In embodiments, resilient member  175  may be a switch (e.g., a pushbutton) to provide, for example without limitation, redundancy with pushbutton  170 , or to provide additional or alternative sensing modalities (e.g., increased pressure sensing range, and/or sensing related to side-to-side jaw motion). In embodiments, resilient member may be operatively coupled to pushbutton  170  and/or transponder  160  via conductors (not explicitly shown). 
         [0031]    In embodiments, wireless switch  110  includes a power source (not explicitly shown), such as without limitation, a battery, a saline fuel cell, or a thermoelectric device. In embodiments, the power source may be initially provided in an inactive state, for example, during manufacture, shipping, and storage. It in envisioned the power source may be activated prior to using the wireless switch by the first application of force sufficient to compress and/or deform resilient housing  112 , as further described hereinbelow. 
         [0032]    In use, e.g., during an electrosurgical procedure, wireless switch  110  may be held between the user&#39;s teeth, e.g., between the maxillary and mandibular teeth of the user (e.g., the surgeon). Initially, wireless switch  110  may be held between the teeth using minimal force, e.g., force sufficient to retain wireless switch  110  in place without significant compression and/or deformation of resilient housing  112 . Thereafter, the user may bite down on wireless switch  110  using increased force, e.g., force sufficient to compress and/or deform resilient housing  112 , which in turn activates pushbutton  170  as best illustrated in  FIG. 3C . In response, transponder  160  communicates the switch state to an interrogator  225  included in an electrosurgical system unit  210  (described hereinbelow) which consequently activates an RF generator  240  that is operably coupled to an electrosurgical instrument  250  to deliver electrosurgical energy to tissue. In embodiments, the pushbutton  170  is configured to sense and/or measure continuous pressure imposed thereon and convey a signal proportionate thereto. 
         [0033]    In another aspect, the present disclosure provides an electrosurgical system  200  having an electrosurgical system unit  210  that includes a controller  230  in operative communication with an interrogator  225 , a generator  240 , and a user interface  220 . Controller  230  may include a processor (not explicitly shown) for executing a set of program instructions stored in memory (not explicitly shown) such as without limitation, SRAM, DRAM, flash memory, disk memory, EEPROM, or any other suitable memory now or in the future known. Additionally or alternatively, controller  230  may include a suitable analog circuit. Electrosurgical system unit  210  includes a user interface  220  which may include an input control (e.g., hand-switch, footswitch, rotary control, button, touchscreen, and the like), output indicators (e.g., visual displays, audio tones, haptic devices, and the like). 
         [0034]    Electrosurgical system unit  210  includes a generator  240  that is configured to deliver electrosurgical energy to electrosurgical instrument  250 . Generator  240  and/or electrosurgical instrument  250  may be configured for monopolar and/or bipolar modes of operation. Electrosurgical system unit  210  includes a controller  230  that is configured and/or programmed to control the operation of generator  240 , including without limitation the intensity, duration, and waveshape of the generated electrosurgical energy, and/or accepting input, such as without limitation user input and sensor input. Generator  240  may generate any suitable energy, such as without limitation RF (radio frequency), microwave, ultrasound, infrared, ultraviolet, laser, thermal energy or other energy. 
         [0035]    Generator  240  may be operably coupled to electrosurgical instrument  250  by cable  255 , which includes at least one conductor (not explicitly shown). In embodiments, cable  255  may couple a sensor (not explicitly shown) included in electrosurgical instrument  250  to generator  240  configured to convey a biological property at the operative site, for example without limitation, temperature, pressure, and/or impedance, to electrosurgical system unit  210 . It is contemplated that generators such as those sold by Valleylab, a division of Covidien, located in Boulder, Colo. may be used as a source of electrosurgical energy, e.g., Ligasure® Generator, FORCE EZ® Electrosurgical Generator, FORCE FX® Electrosurgical Generator, FORCE 1C™, FORCE 2™ Generator, SurgiStat® II, FORCETRIAD® or other envisioned generators which may perform different or enhanced functions. One such system is described in commonly-owned U.S. Pat. No. 6,033,399 entitled “ELECTROSURGICAL GENERATOR WITH ADAPTIVE POWER CONTROL.” Other systems have been described in commonly-owned U.S. Pat. No. 6,187,003 entitled “BIPOLAR ELECTROSURGICAL INSTRUMENT FOR SEALING VESSELS.” 
         [0036]    Electrosurgical system unit  210  includes an interrogator  225  and antenna  215  configured to wirelessly communicate with transponder  160 . In use, electrosurgical system unit  210  may be powered up by a user (e.g., typically, a surgeon or clinician). The controller  230  may perform a power-on self test (POST) to verify proper operation of electrosurgical system unit  210 . In one aspect, electrosurgical system unit  210  may be operably associated (e.g., “married”) with a unique wireless switch  110  such that wireless activation of electrosurgical system unit  210  is only possible by actuation of a designated unique wireless switch  110 . Such association may be desirable to eliminate the risk of inadvertent actuation by a superfluous wireless switch  110  that may be within operating proximity of electrosurgical system unit  210  (e g., present in an adjacent operating room, for example). In embodiments, a wireless switch  110  may be associated with electrosurgical system unit  210  by a “marrying” process consisting of receiving a user input indicating the marrying process is to be initiated, transmitting an identification request from the interrogator  225  to a wireless switch  110 , responding to the identification request by transmitting from the wireless switch  110  an identification response, and storing the identification response. In embodiments, the marrying process may include the steps of actuating the wireless switch  110  in a predetermined manner, such as without limitation, three actuations within a three seconds period of time, or, as another example, one long actuation having a duration of about one second, followed by one short actuation having a duration of about one-quarter of a second, followed by one long actuation having a duration of about one second. 
         [0037]    In embodiments, the electrosurgical system unit  210  is selectively operable in a standby mode or an active mode. In standby mode, the activation of electrosurgical RF generator  240  is inhibited, e.g., actuation of wireless switch  110  will not cause activation of electrosurgical RF generator  240  and/or electrosurgical energy. In embodiments, actuation of wireless switch  110  while electrosurgical system unit  210  is in a standby mode will cause an output indication e.g., a visual, audio, or tactile indication. Such an indication may allow to user to confirm operation of the system (e.g., that the wireless switch  110  was successfully “married” to the electrosurgical system unit  210 ) prior to commencement of surgery. In active mode, actuation of wireless switch  110  causes activation of electrosurgical RF generator  240  and/or electrosurgical energy. In embodiments, actuation of wireless switch  110  while electrosurgical system unit  210  is in an active mode will cause an output indication e.g., a visual, audio, or tactile indication. In embodiments, an output indication issued while in standby mode is distinct from an output indication issued while in active mode. By way of example only, a standby mode actuation indication may be characterized by a pulsed beep tone, while an active mode actuation indication may be characterized by a continuous beep tone. 
         [0038]    In one aspect, interrogator  225  may communicate with transponder  160  in a continuous poll and response fashion. An interrogation signal is communicated from interrogator  225  to wireless switch  110  (e.g., polling). The interrogation signal is received by antenna  165  and consequently delivered to transponder  160 . In embodiments, the interrogation signal includes an identifier derived at least in part from the association (e.g., “marrying”) procedure previously described. In response to an interrogation signal, transponder  160  senses the state of switch  170 , and generates a response signal that conveys the switch state (e.g., the response). The response signal is received by antenna  215  and communicated to interrogator  225 , which, in turn, conveys the switch status to controller  230 . The poll and response cycle may repeat iteratively. In embodiments, the poll and response cycle repeats at a rate in the range of about once per second to about a thousand times per second. In embodiments, the poll and response cycle repeats at a rate of about one hundred time per second. Advantageously, the poll and response cycle is repeated such that system latency is negligible, e.g., a delay between actuating/deactuating switch  170  and the corresponding activation/deactivation of generator  240  is imperceptible to the surgeon, and/or clinically unremarkable. In embodiments, at least part of the energy of the interrogation signal induces an electrical current in antenna  165  sufficient to power transponder  160 . 
         [0039]    In embodiments, interrogator  225  and antenna  215  may be included within electrosurgical system unit  210 . In yet other envisioned embodiments, interrogator  225  and antenna  215  may configured as an independent unit adapted to interoperate with existing electrosurgical generators (e.g., in a piggyback or retro-fit configuration). 
         [0040]    Turning now to  FIG. 5A , an embodiment of a bite-activated wireless switch  310  in accordance with the present disclosure includes a housing  340  that is included in a substantially mouthguard-shaped support  320 . In embodiments, the mouthguard-shaped support  320  may be custom-fitted to a user&#39;s mouth, incorporating, for example, a custom-fitted biting surface  330  formed from an impression of the user&#39;s teeth. Housing  340  may be integrally formed with mouthguard-shaped support  320 , or, alternatively, housing  340  may be detachably coupled to mouthguard-shaped support  320 .  FIG. 5B  illustrates yet another embodiment of a bite-activated wireless switch  410  in accordance with the present disclosure that includes a housing  440  that is included in support member  420  that is contoured in a truncated mouthguard-like shape that is adapted to be held between, for example, the user&#39;s maxillary and mandibular incisors, canines, or molars. 
         [0041]    While several embodiments of the disclosure have been shown in the drawings and/or discussed herein, it is not intended that the disclosure be limited thereto, as it is intended that the disclosure be as broad in scope as the art will allow and that the specification be read likewise. Therefore, the above description should not be construed as limiting, but merely as exemplifications of particular embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto.