Abstract:
A gas-enhanced electrosurgical method and apparatus for coagulating tissue. The apparatus includes a first tube with a proximal end and a distal end. The proximal end of the first tube is configured to receive pressurized ionizable gas. The distal end of the first tube is configured to deliver ionized gas towards a treatment area. The apparatus also includes at least one electrode positioned to selectively ionize the pressurized ionizable gas before the pressurized ionizable gas exits the distal end of the first tube. The electrode is adapted to operatively couple to an electrical energy source. The apparatus also includes a second tube with proximal and distal ends. The second tube is configured to selectively evacuate the ionized gas and dislodged tissue material from the treatment area.

Description:
CROSS-REFERENCED TO RELATED APPLICATION 
       [0001]    This application is a Continuation application of U.S. patent application Ser. No. 11/370,287 filed on Mar. 8, 2006, the entire contents of which is incorporated herein by reference in its entirety. 
     
    
     TECHNICAL FIELD 
       [0002]    The present disclosure relates to gas-enhanced electrosurgical methods and devices. More particularly, the present disclosure relates to a gas-enhanced electrosurgical device and method for supplying gas to and removing gas from a surgical site. 
       BACKGROUND OF RELATED ART 
       [0003]    Over the last several decades, more and more surgeons are abandoning traditional open methods of gaining access to vital organs and body cavities in favor of endoscopes and endoscopic instruments that access organs through small puncture-like incisions. Endoscopic instruments are inserted into the patient through a cannula, or a port that has been made with a trocar. Typical sizes for cannulas range from about three millimeters to about twelve millimeters. Smaller cannulas are usually preferred, and this presents a design challenge to instrument manufacturers who must find ways to make surgical instruments that fit through the cannulas and operate in a safe and effective manner. 
         [0004]    Devices for arresting blood loss and coagulating tissue are well known in the art. For example, several prior art instruments employ thermic coagulation (heated probes) to arrest bleeding. However, due to space limitations, surgeons can have difficulty manipulating an instrument to coagulate, desiccate, fulgurate and/or cut tissue. Other instruments direct high frequency electric current through the tissue to stop the bleeding. Eschar adherence may also be a problem with these instruments. In both types of instruments, the depth of the coagulation is difficult to control. 
         [0005]    Using these instruments to treat certain more sensitive tissue sites may be impractical since the constant and/or direct emission of ionized gas/plasma at the tissue may cause unintended results. Moreover, simply controlling the pressure of the gas from the source may not be effective or yield a desired result. 
       SUMMARY 
       [0006]    The present disclosure relates to an electrosurgical apparatus and method for coagulating tissue. An electrosurgical apparatus includes a first tube with a proximal end and a distal end. The proximal end is configured to receive pressurized ionizable gas and the distal end is configured to deliver ionized gas towards a treatment area. The electrosurgical apparatus also includes at least one electrode positioned to selectively ionize the pressurized ionizable gas prior to the pressurized ionizable gas exiting the distal end of the first tube. The electrode is adapted to be operatively coupled to an electrical energy source. The electrosurgical apparatus also includes a second tube with proximal and distal ends. The second tube is configured to selectively evacuate the ionized gas and dislodged tissue material from the treatment area. 
         [0007]    In one embodiment, the first tube is concentrically disposed within the second tube. 
         [0008]    In an exemplary embodiment, the distal end of the first tube extends distally relative to the distal end of the second tube. 
         [0009]    The electrode may be activated with a first electrical potential and the electrical energy source may include a remote patient pad that is energized to a second electrical potential. 
         [0010]    In an embodiment of the disclosure, the electrosurgical apparatus is configured for use in a bipolar mode wherein the first tube is activated with a first electrical potential and the second tube is activated with a second electrical potential. 
         [0011]    In an exemplary embodiment, the electrosurgical apparatus includes a regulator which regulates the flow of pressurized argon through the first tube. The regulator is disposed between a gas supply of the pressurized argon and the proximal end of the first tube. 
         [0012]    In another embodiment of the disclosure, the electrosurgical apparatus includes a fluid agitator, which may be disposed within the first tube, to impart non-laminar flow characteristics to the pressurized ionizable gas. Here, the pressurized ionizable gas may be used to cool tissue. 
         [0013]    The present disclosure also relates to an electrosurgical apparatus for coagulating tissue that is configured to use in a bipolar mode. In this embodiment, an electrode control mechanism that controls the current intensity to the electrode is disclosed. 
         [0014]    The present disclosure also relates to a method for coagulating tissue. The method includes the steps of providing an electrosurgical apparatus including a first tube configured to receive pressurized ionizable gas and to deliver ionized gas towards a treatment area, at least one electrode positioned to selectively ionize pressurized ionizable gas prior to the pressurized ionizable gas exiting the first tube, and a second tube being configured to selectively evacuate the ionized gas and dislodged tissue material from the treatment area. The remaining steps include inserting the electrosurgical apparatus into tissue; delivering ionizable gas to the first tube; ionizing pressurized ionizable gas; delivering pressurized ionized gas through the first tube towards the treatment area; and removing pressurized ionized gas from the treatment area via the second tube. Additionally, a step of inserting an introducer into the tissue is disclosed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]      FIG. 1  is a perspective view of an electrosurgical instrument according to an embodiment of the present disclosure; 
           [0016]      FIG. 2  is an enlarged, side sectional view of one embodiment of the present disclosure showing a first tube and a second tube inserted into tissue; 
           [0017]      FIG. 3  is an enlarged, side sectional view of the area of detail shown in  FIG. 2 ; 
           [0018]      FIG. 4  is an end cross-sectional view of the first tube and the second tube according to one embodiment of the present disclosure; 
           [0019]      FIG. 5  is an enlarged, schematic sectional view of the first tube and the second tube illustrating ionized gas treating a tissue surface; 
           [0020]      FIG. 6  is an enlarged, schematic sectional view of the first tube and the second tube illustrating a helically-shaped baffle located with the first tube for causing ionizable gas and/or ionized gas to exit the first tube with predetermined flow characteristics; 
           [0021]      FIG. 7A  is an enlarged, schematic sectional view of the first tube and the second tube wherein the first tube includes a rotating plenum having an aperture therein for causing ionizable gas and/or ionized gas to exit the first tube with predetermined flow characteristics; 
           [0022]      FIG. 7B  is a cross-sectional view of the embodiment of  FIG. 7A  taken along line  7 B- 7 B; 
           [0023]      FIG. 8A  is an enlarged, schematic sectional view of the first tube and the second tube wherein the first tube includes a pair of elongated flaps therein for causing ionizable gas and/or ionized gas to exit the first tube with predetermined flow characteristics; and 
           [0024]      FIG. 8B  is a cross-sectional view of the embodiment of  FIG. 8A  taken along line  8 B- 8 B. 
       
    
    
     DETAILED DESCRIPTION 
       [0025]    Referring to  FIG. 1 , a gas-enhanced tissue coagulator generally identified by reference numeral  10  is shown extending through a working channel of an endoscope  12 . The coagulator  10  may be employed with a variety of suitable endoscopes, such as those manufactured by Olympus, Pentax and Fujinon. As such, only the basic operating features of the endoscope  12  that work in combination with the present disclosure need to be described herein. 
         [0026]    Generally, the endoscope  12  includes a hand piece  26  having a proximal end  27  and a distal end  29 . The proximal end  27  is mechanically coupled to a supply  19  of pressurized ionizable gas, e.g., inert gas, via hose  20  and electrically coupled to an electrosurgical generator  22  by way of cable  24  to supply electrosurgical energy, e.g., high frequency coagulation current, to the endoscope  12 . The electrosurgical generator  22  may be configured to selectively control the amount of electrosurgical energy transmitted to an electrode during a surgical procedure. The supply  19  of pressurized ionizable gas may be configured to selectively control the rate of flow of gas, which is typically greater than 1 liter per minute. 
         [0027]    As shown in  FIGS. 1 and 2 , a long, generally flexible tubular member  13  having a first tube  100  located within a second concentric tube  200  is mechanically coupled to the distal end  29  of the hand piece  26 . First tube  100  includes a proximal end  110  and a distal end  120  and second tube  200  includes a proximal end  210  and a distal end  220 . As best illustrated in  FIG. 4 , first tube  100  and second tube  200  are concentrically oriented, such that first tube  100  is disposed within second tube  200 . First tube  100  and second tube  200  may include insulation coatings  102 ,  202 , respectively, to electrically isolate tubes  100  and  200  from one another. Distal end  120  of the first tube  100  extends distally from the distal end  220  of the second tube  200 , the purposes of which are explained in more detail below. 
         [0028]    Turning now to  FIG. 2 , an enlarged, side sectional view of one embodiment of the coagulator  10  is shown. First tube  100  and second tube  200  are shown inserted into tissue, generally designated as “N.” The first tube  100  is configured to deliver ionizable gas towards a treatment area “T” out of its distal end  120 . The proximal end  110  of the first tube  100  is configured to receive ionizable gas from the supply  19 . Second tube  200  is configured to remove or evacuate gas and/or waste from the treatment area “T” through distal end  220 . The gas and/or waste exits through proximal end  210  and is typically collected in a known manner such as a suitable medical waste container or a waste containment system. An introducer  300  may be utilized to facilitate the insertion of the coagulator  10  into the tissue “N”. 
         [0029]    With continued reference to  FIGS. 1 and 2 , ionizable gas, e.g., argon, is supplied to the proximal end  110  of the first tube  100  by a gas conduit (not explicitly shown) located inside tubular member  13 . Ionizable gas  19  may be supplied to the first tube  100  at a selectable, predetermined flow rate. The flow rate of the ionizable gas may be selectively adjustable and/or regulated via a pressure regulator  21  depending upon a particular purpose or a particular surgical condition. 
         [0030]    As mentioned above, the ionizable gas is supplied under pressure to the proximal end  110  of the first tube  100  and flows generally within the first tube  100  towards distal portion  120 . An electrode  48  (see  FIG. 5 ) discharges an electrosurgical current, e.g., radio frequency (RF), which ionizes the gas prior to the gas being expelled from the distal end  110  of the first tube  100  towards tissue “N.” (Ionizable gas is illustrated as dashed arrows  18  in  FIG. 5  and the resulting ionized gas is illustrated by the area designated as reference numeral  46 .) The stream of ionized gas  46  conducts current to the tissue  50  while effectively scattering blood away from the treatment site allowing the tissue  50  to readily coagulate and arrest bleeding. The ionized gas  46  along with any vaporized material  52  is then suctioned away from the tissue (in the direction indicated by arrows A) through distal end  220  of second tube  200  via a suitable suctioning device (not explicitly shown). As best shown in  FIG. 5 , the generally wide ionized gas area allows a surgeon to effectively coagulate a wide tissue area. This is commonly referred to as a “coagulative painting.” 
         [0031]    Electrode  48  is connected by way of an electrical conduit disposed within the first tube  100 , which is ultimately connected to the electrosurgical generator  22 . The electrode  48  may be ring- or pin-type and is spaced from the distal opening  110  of the first tube  100  such that the electrode  48  does not come into contact with the tissue “N” or tissue  50  during the surgical procedure. In one embodiment of the present disclosure, an electrode control mechanism  60  allows an operator to control the current intensity to the electrode  48  during surgical procedures. 
         [0032]    Ionizable gas  18  is controlled/manipulated such that it flows through the first tube  100  in a generally non-laminar or turbulent manner. However, various systems may be employed to cause the ionizable gas  18  to flow more or less turbulently or with other predetermined flow characteristics through the first tube  100 . The gas flow may be used to cool tissue, thus reducing thermal margins or areas of ablated tissue during coagulation. 
         [0033]    A fluid agitator, for example, such as a ribbon  62  (see  FIG. 1 ), may be positioned within the first tube  100  to cause ionizable gas  18  and/or ionized gas  46  to swirl therewithin prior to the ionizable gas  18  and/or ionized gas  46  exiting the distal end  110  of the first tube  100 . Additionally, with reference to  FIG. 6 , a generally helically-shaped baffle  64  may be positioned within the first tube  100  to cause ionizable gas  18  and/or ionized gas  46  to swirl within first tube  100  prior to the gas  18  or  46  exiting distal end  120  of first tube  100 . 
         [0034]    A rotatable plenum  66  is illustrated in  FIGS. 7A and 7B , which includes at least one aperture  68  located therethrough. In this embodiment, the force of the ionizable gas  18  and/or ionized gas  46  flowing through aperture  68  causes the plenum  66  to rotate, which in turn causes the ionizable gas  18  and/or ionized gas  46  to swirl with predetermined flow characteristics. It is envisioned that the user can control the rotational speed of the plenum  66  by varying the pressure of ionizable gas  18  and/or ionized gas  46  flowing through first tube  100 . It is also envisioned that the rotational speed of the plenum  66  is controlled by a separate mechanism that is independent of the ionizable gas  18  and/or ionized gas  46 , e.g., a regulator (not explicitly shown). 
         [0035]      FIGS. 5A and 8B  illustrate a flow system that includes a pair of rods  70  disposed within first tube  100  for supporting a pair of elongated flaps  72 . Under flow conditions, flaps  72  attenuate/extend from rods  70  and flutter within the stream of ionizable gas  18  and/or ionized gas  46 , It is envisioned that the force of ionizable gas  18  and/or ionized gas  46  flowing through first tube  100  causes each flap  72  to flutter, which in turn causes ionizable gas  18  and/or ionized gas  46  to move in a more turbulent manner. It is also envisioned that the rate/frequency of the flutter is directly related to the pressure of ionizable gas  18  and/or ionized gas  46  flowing through first tube  100 . Any suitable number of flaps  72  can be employed to create certain flow conditions, e.g., a series of flaps  72  can be positioned at various positions along first tube  100  to create a more turbulent flow of ionizable gas  18  and/or ionized gas  46 . Moreover, the length of each flap  72  may be varied to create additional flow effects. 
         [0036]    Coagulator  10  may be configured for monopolar and/or bipolar modes. In the monopolar mode, the first tube  100  may be the active electrode and a patient pad  17  ( FIG. 5 ) may be the return electrode. In the monopolar mode, an arcing pattern  410  ( FIG. 3 ) may radiate out from the distal end  120  of the first tube  100 . In the bipolar mode, the first tube  100  may be the active electrode and the second tube  200  may be the return electrode. In the bipolar mode, the conductive path, represented by dashed lines  420 , would be relatively self-contained at the distal end  120  of the first tube  100  due to the proximity of the active electrode and the return electrode. In one embodiment, monopolar and bipolar modes may be alternated a plurality of times per second during use, which would enable the conductive path in monopolar mode to arc into the surrounding tissue  50  causing desiccation and vaporization of the tissue  50  in close proximity to the distal end  120  of the first tube  100 . The conductive path in bipolar mode further desiccates material that has been separated from the tissue  50  as the conductive path enters the second tube  200 . 
         [0037]    In operation, the introducer  300  may be inserted through the body and placed into tissue “N.” A stylet (not shown) may facilitate the insertion of the introducer  300  into the tissue “N” by taking impedance readings. The stylet may then be removed upon confirmation of a desired impedance reading. Tubular member  13  of the coagulator  10  may then be inserted into the introducer  300 , providing free access to the tissue “N.” Once tubular member  13  is place in the tissue “N,” the gas flow may be selectively initiated and the electrode  48  is thereafter selectively activated. A corona electrode may be used for inducing ignition of the ionizable gas  18 . Ionized gas  46  flows out of the first tube  100  and is suctioned back into the second tube  200 . When argon gas is used, the argon restricts the amount of tissue affected to the material that is adjacent the distal end  120  of the first tube  100 . Nuclear material near the distal end  120  of the first tube  100  is thus vaporized and removed via the second tube  200 . 
         [0038]    From the foregoing and with reference to the various figures, those skilled in the art will appreciate that not only can the coagulator  10  of the present disclosure be used to arrest bleeding tissue, but the present disclosure can also be employed for desiccating and/or removing the surface tissue, eradicating cysts, forming eschars on tumors or thermically marking tissue. Those skilled in the art will also appreciate that certain modifications can be made to the present disclosure without departing from the scope of the present disclosure. 
         [0039]    For example, the coagulator  10  of the present disclosure may include articulating qualities. In addition, tubular member  13 , or at least a portion thereof, may have an arcuate shape. Moreover, the coagulator  10  of the present disclosure may be used while performing liposuction and/or for treating tumors. In such tumor-treating embodiments, a level of coagulation may be achieved and the second tube  200  may remove material, as opposed to coagulating the tissue and leaving it in the body. Furthermore, certain aspects of the present disclosure may be utilized with a portable device and a portable argon supply. 
         [0040]    There is described and illustrated herein several embodiments of a gas-enhanced electrosurgical device that supplies gas to and removes gas from a treatment area. While particular embodiments of the disclosure have been described, 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 various embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto.