Abstract:
A cautery device includes an elongated handpiece extending axially from a proximal end to a distal end and a cautery tip extending coaxially with the handpiece from the distal end of the handpiece. The tip defines a channel extending coaxially with the handpiece along an entire length of the cautery tip from a proximal open end to a distal open end. The device includes a gas supply connection extending from the proximal end of the handpiece for supplying gas to the cautery tip. The gas supply connection is fluidly coupled to the cautery tip. The device includes an electric supply connection extending from the proximal end of the handpiece for supplying electricity to the cautery tip. The electric supply connection is electrically coupled to the cautery tip. The gas supplied to the cautery tip is introduced to the channel at the proximal open end and exits the tip at the distal open end.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of priority under 35 U.S.C. §119(e) to provisional application 62/075,897, filed on Nov. 6, 2014, the entire contents of which are incorporated herein by reference in their entirety. 
     
    
     BACKGROUND 
       [0002]    1. Field 
         [0003]    The present invention relates to surgical instruments, and more particularly a cautery apparatus. 
         [0004]    2. State of the Art 
         [0005]    Cautery devices have been used in surgical procedures to perform cutting and coagulation of tissue and blood vessels. Typically, cautery devices are “pen”-like devices that a surgeon can grasp by the hand to use. The cautery device typically is connected to an electrical generator that outputs a level of current that is conducted to a tip of the device to achieve the desired cutting and/or coagulation effect during a surgical procedure. 
         [0006]    The use of cautery devices on tissue results in the generation of smoke and vapor, which are unwanted byproducts that reduce visibility in the area of the tip. Also, cautery devices have the potential to provide enough energy to cause fires in an operating room environment, which is typically a high oxygen environment. Approximately 500 operating room fires occur in the United States each year, the vast majority of which are related to a cautery device. 
       SUMMARY 
       [0007]    According to a first aspect, a cautery device includes an elongated handpiece extending axially from a proximal end to a distal end and a cautery tip extending coaxially with the handpiece from the distal end of the handpiece. The tip defines a coaxial channel extending from the handpiece and along an entire length of the cautery tip from a proximal open end to a distal open end. The device includes a gas supply connection extending from the proximal end of the handpiece for supplying gas to the cautery tip. The gas supply connection is fluidly coupled to the cautery tip. The device includes an electric supply connection extending from the proximal end of the handpiece for supplying electricity to the cautery tip. The electric supply connection is electrically coupled to the cautery tip. The gas supplied to the cautery tip is introduced to the channel at the proximal open end and exits the tip at the distal open end. 
         [0008]    According to a second aspect, the cautery device includes a multilumen tube extending from the proximal end of the handpiece. The tube defines a gas lumen extending along substantially the entire length of the tube and defining at least one electrical conductor lumen coextensive with the gas lumen. The gas lumen is in fluid communication with the cautery tip and supplies gas to the cautery tip. The gas supplied to the cautery tip is introduced to the channel at the proximal open end and exits the tip at the distal open end. The device also includes at least one electrical conductor extending through the at least one electrical conductor lumen. The electrical conductor is electrically coupled to the cautery tip for supplying electricity to the cautery tip. 
         [0009]    According to a third aspect, the cautery device includes a switch configured to regulate the supply of electric power to the cautery tip based on the position of the handpiece relative to a holder that is constructed to receive the handpiece. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1 a    is an isometric view of an embodiment of a cautery device. 
           [0011]      FIG. 1 b    is a detailed cutaway section view of the cautery device of  FIG. 1 a    with a portion of a housing removed for purposes of illustration. 
           [0012]      FIG. 2  is an assembly drawing of a valve train and an electrical unit of the cautery device shown in  FIGS. 1 a    and  1   b.    
           [0013]      FIG. 3  shows a view of the cautery device of  FIG. 1 a    along section  3 - 3  in  FIG. 1   a.    
           [0014]      FIG. 4  shows a view of a portion of the cautery device along section  4 - 4  in  FIG. 3 . 
           [0015]      FIG. 5 a    shows the cautery device of  FIG. 1 a    configured with an integrated multilumen gas and electrical conductor arrangement. 
           [0016]      FIG. 5 b    shows the multilayer tubing of  FIG. 5 a    along section  5   b - 5   b  in  FIG. 5   a.    
           [0017]      FIG. 6  is a schematic view of the electrical unit of  FIG. 2 , shown connected to a magnetic reed switch. 
           [0018]      FIG. 7  shows a cautery device disposed in a holder. 
       
    
    
     DETAILED DESCRIPTION 
       [0019]      FIG. 1A  shows an embodiment of a cautery device  100  that includes an elongated housing  102  that extends longitudinally along an axis A-A from a proximal end  104  to a distal end  106 . The device  100  also includes a removable hollow cautery tip  108  that extends longitudinally from the housing coaxially with axis A-A. The cautery tip  108  defines an open channel  110  that extends axially completely through the tip  108 . The open channel  110  is preferably coaxial with the axis A-A. The housing  102  defines a handpiece  112  that is arranged so that it may be grasped in a user&#39;s hand like a writing instrument to direct the cautery tip  108  during a surgical procedure while also allowing a user of the device  100  to actuate buttons  114 ,  116  that extend from the housing  102 . As will be described in greater detail below, the cautery tip  108  receives electric power to operate the tip  108  so that it can be used to perform various cautery tool procedures, such as cutting and coagulation. Also, the cautery device  100  is constructed to selectively permit gas to flow through the open channel  110  of the cautery tip  108 . 
         [0020]    The cautery device  100  is operated in various modes in response to selective actuation of one or more of the buttons  114 ,  116 , as will be described in greater detail below. Each of the buttons  114 ,  116  may operate the cautery device  100  in a corresponding mode of operation, such as a coagulation mode and a cutting mode. Also, one or more of the buttons  114 ,  116  may be a multi-function button. For example, each respective button  114 ,  116  may be arranged to both control a gas flow of a gas through the cautery tip  108 , as well as control power output to the cautery tip  108  based on the mode of operation corresponding to each button  114 ,  116 . More specifically, in one embodiment, a first button  114  may correspond to the cutting mode and a second button  116  may correspond to the coagulation mode. In such an embodiment, selectively actuating the first button  114  may set a first gas flow rate through the cautery tip  108  and a power level corresponding to the cutting mode, while selectively actuating the second button  116  may set a second gas flow rate to the cautery tip  108  and a power level corresponding to the coagulation mode. Thus, a user of the device  100  may select the operating mode of the device by selecting and pressing a corresponding button  114 ,  116 . 
         [0021]    A power cord  118  and a gas tube  122  extend from the proximal end  104  of the cautery device  100 . The power cord  118  supplies electric power to the device  100  from an electric power supply  120 . The gas tube  122  supplies a gas to the device  100  from a source of pressurized gas  124 . The gas may be an inert gas such as carbon dioxide or nitrogen. Preferably, the gas is heavier than oxygen to drive away oxygen from the area proximate to the cautery tip  108  so that the gas issuing from the cautery tip  108  can create a non-flammable zone around the tip  108 . 
         [0022]      FIG. 1B  shows the cautery device  100  with a portion of the housing  102  removed for purpose of illustrating some housed elements of the device  100 . The device  100  includes a valve train  126  coupled to the buttons  114 ,  116 . The valve train  126  has a proximal end  128  that is formed as a barbed male coupler  130  for coupling to a distal end of the tubing  122  ( FIG. 1A ). The valve train  126  also has a distal end  132  that may be formed as a female quick-connect tube coupler  134  for removably coupling to a proximal end  136  of the cautery tip  108 . 
         [0023]    In the embodiment shown in  FIG. 1B , the valve train  126  includes a first valve  138  that may be actuated by the first button  114  and includes a second valve  140  that may be actuated by the second button  116 . In one embodiment the valves  138 ,  140  are biased so that they are normally-closed valves such that the user must depress the respective button to open the valves  138 ,  140 . When the cautery tip  108  is fluidly coupled to the valve train  126 , the valve train  126  controls the flow of pressurized gas through the tip assembly by operation of the valves  138 ,  140 , which are actuated using the buttons  114 ,  116 . 
         [0024]    The cautery tip  108  is removably coupled in a collet  144  that is provided at the distal end of the handpiece  112 . The cautery tip  108  extends through the collet  144 . More specifically, when the cautery tip  108  is fully coupled to the handpiece  112 , as shown in  FIG. 1B , the cautery tip  108  is fluidly coupled to the valve train  126  and is electrically coupled to an electrical unit  146  (shown partially concealed beneath the valve train  126  in  FIG. 1B ) via an electrical coupler  148 , as will be described in greater detail below. 
         [0025]    In the embodiment shown in  FIGS. 1A and 1B , the cautery tip  108  has a generally cylindrical, proximal portion  150  that extends through the collet  144  and to the fluid and electrical couplers  134 ,  148 . The cautery tip  108  also has a flattened distal portion  152 . The cylindrical proximal portion  150  tapers to the flattened distal portion  152  distally of the collet  144 . The cautery tip  108  is formed of a metal that is coated with a conductive polymer. A silicone cover may also be applied to a portion of the tip  108  between the flattened portion  152  and the collet  144 . The flattened distal portion  152  has a generally rectangular cross-sectional profile. It will be appreciated, however, that the cautery tip  108  may have other profiles than that shown in  FIG. 1B . The cautery tip  108  is removably coupled to the handpiece  112  to facilitate tip replacement and interchanging different cautery tips (e.g., with different forms) with the same handpiece  112 . To provide such interchangeability, the electrical and fluid couplers  148  and  134  may be constructed as removable couplers, such as a fluid quick-connect coupler and an electrical socket, respectively. 
         [0026]    The electrical unit  146  is electrically connected to the wire  118 . The electrical unit  146  controls the flow of electrical power to the tip  108  to operate the device  100  in one of its operating modes through actuation of the aforementioned buttons  114 ,  116 . 
         [0027]    As shown in  FIG. 2 , in one embodiment, the electrical unit  146  may be constructed as a printed circuit board  200  having a plurality of circuits  202 ,  204  from the power source to the electric coupler  148 . Each of the circuits  202 ,  204  may correspond to a respective one of the buttons  114 ,  116  and, therefore, to a mode of operation of the device  100 . Specifically, circuit  202  includes a first switch  206  that may be actuated by the first button  114  and circuit  204  includes a second switch  208  that may be actuated by the second button  116 . Each circuit  202 ,  204  may be constructed to regulate the power level delivered to the cautery tip  108  when the respective switches  206 ,  208  are actuated. For example, a first circuit  202  may be activated by the first switch  206  to energize the tip  108  so that it can cut tissue (e.g., a cutting mode), while the second circuit  204  may be activated by the second switch  208  to energize the tip  108  so that it can coagulate fluid (e.g., a coagulation mode). 
         [0028]    By way of example, in one embodiment, button  114  may be used to operate the device  100  in a cutting mode and button  116  may be used to operate the device  100  in a coagulation mode. A surgeon may press button  114  to simultaneously open the first valve  138  to allow for the gas to flow at a first flow rate to the tip assembly  142  and to energize the first circuit  202  to supply electrical energy to the tip  108  sufficient for operating the device  100  in a cutting mode. Similarly, a surgeon may press the second button  116  to open the second valve  140  to allow for a second gas flow rate to the tip assembly  142  and to simultaneously energize the second circuit  204  to supply electrical energy to the tip  108  sufficient for operating the device  100  in a coagulation mode. The first and second flow rates may be the same or different based on the operating mode selected by pressing the associated buttons  114 ,  116 . The first and second flow rates are sufficient to supply the gas at least in a quantity to the open end of the tip  108  to create a zone about the tip which is not flammable when the device is operated in any of its operating modes, e.g., coagulation or cutting. Also, each of the first and second flow rates may be variable based on the range of motion (distance the button is depressed) of the switch button. 
         [0029]    In one embodiment, the flow of gas and electricity to the cautery tip  108  may be interlocked together so that a flow of gas is initiated only when the tip  108  is energized in one of its operating modes (e.g. cutting or coagulation). Also, in another embodiment, the flow of gas may be initiated without (independently of) energizing the tip  108 . For example, the buttons  114  and/or  116  may have a range of motion in which an initial range of motion (i.e., of button depression) of the button may only permit gas to flow and a secondary range of motion (i.e., further button depression) of the button may cause both gas and electricity to flow to the tip. The flow of gas and electricity may thus occur together or without electricity (i.e., gas only). 
         [0030]    The construction of the valve train and the operation of the gas and electricity flow will now be described in greater detail.  FIG. 3  shows cutaway section views of the valve train  126  shown in  FIG. 1B . 
         [0031]      FIG. 3  shows a section view of the device  100  along section  3 - 3  in  FIG. 1A . As shown in  FIG. 3 , the valves  138  and  140  are arranged as gate valves. The construction of valve  138  will now be described. It will be appreciated that the construction of valve  140  may be the same, although dimensions may be different. Valve  138  has a valve body  302  that is disposed in the first channel  402  ( FIG. 4 ) of the valve train  126 . Valve  138  has a valve stem  304  that is received in a vertical bore  306  of the body  302  that intersects with the first channel  402  ( FIG. 4 ). The valve stem  304  has a teardrop shaped port  308  formed therein, which is tapered towards the bottom of the valve stem  304  and is enlarged toward the top of the valve stem  304 . The valve stem  304  is coupled to the first button  114 . A coil spring  310  is interposed between the button  114  and the body  302  to bias the valve stem  304  in an upward, closed position in which the port  308  is not in communication with the first channel  402 , as is shown in  FIG. 3 . When the valve stem  304  is positioned as shown in  FIG. 3 , the stem  304  is seated in the housing and fully blocks the port  308  to maintain the valve  138  in a closed position. The valve stem  304  is constructed to move vertically in the vertical bore  306  so as to progressively open and close the flow of gas through the port  308  and the first gas channel  402 . 
         [0032]    The electrical unit  146  is shown below the valve train  126 . The first switch  206  is aligned with the valve stem  304 . A first coil spring  312  extends upward from the first switch  206 . When the first valve  138  is in the fully closed position, the spring is spaced from the bottom of the valve stem  304 . The first switch  206  may be constructed to actuate in response to compression of the first coil spring  312 . 
         [0033]    The valve stem  304  may be moved downward from the closed position by pushing on the button  114  against the force of the spring  310 . As the valve stem  304  moves downward, the bottom of the port  308  will begin to come into fluid communication with the first gas channel  402 , creating a relatively small opening for gas to flow between the port  308  and the first channel  402 . Also, as the bottom of the valve stem  304  moves downward it begins to compress the first coil spring  312 , which causes the first switch  206  to actuate (i.e., to close the first circuit  202 ), permitting power to flow through the first circuit  202  to the cautery tip  108  at a power level regulated by the first circuit  202  and corresponding to a first operation mode. 
         [0034]    As the valve stem  304  is moved progressively further downward, the port  308  is progressively moved further downward enlarging the opening between the port  308  and the first channel  402  until the top of the port  308  is aligned with the top of the channel  402 , in which case the valve  138  is considered to be in a fully open position. The further movement of the valve stem  304 , however, does not change the state of the first circuit  202 , which remains energized owing to the further compression of the first coil spring  312 . Thus, in view of the foregoing description it will be appreciated by one of skill in the art that in at least one embodiment of the cautery device  100  a user can regulate the flow rate of gas through the valve train  126  and the cautery tip  108  by adjusting the travel distance of the button  114 . Such flow regulation may be useful for a surgeon to adjust the flow rates around tissue vessels of different sizes. For example, for blowing gas around small vessels, a user may desire only a relatively small wisp of gas, while for blowing gas around larger vessels, a user may desire a relatively larger flow to displace fluid from the area. 
         [0035]      FIG. 4  shows a detailed section view of the device  100  across section  4 - 4  in  FIG. 3 . The valve train  126  defines the first gas channel  402  in which the stem  304  of the first valve  138  is received and a second gas channel  404  in which a second valve stem  305  ( FIG. 3 ) of the second valve  140  is received. The first and second channels  402 ,  404  both extend from the proximal end  128  to the distal end  132  of the valve train  126 . The first gas channel  402  has a first opening  406  that is aligned with the first bore  306  of the first valve  138 . The first opening  406  receives the first valve stem  304 . The second gas channel  404  has a second opening  410  that is aligned with a second bore  307  ( FIG. 3 ) of the second valve  140 . The second opening  410  receives the second valve stem  305  ( FIG. 3 ) of the second valve  140 . The first valve stem  304  is constructed to move vertically in the opening  406  to actuate the first switch  206  of the first circuit  202  of the electrical unit  146 , which is below the valve train  126 . Similarly, the second valve stem  305  is constructed to move vertically in the opening  410  to actuate the second switch  208  of the second circuit  204  of the electrical unit  146 . The first and second valves  138 ,  140  may be of the same construction or may be different. 
         [0036]    In one embodiment of the device  100 , the first and second buttons  114 ,  116  may be pressed independently of one another and both can be pressed partially between the open and closed valve positions. However, the cautery tip  108  may be configured to operate in only a single operating mode, such as cutting or coagulating. For example, in one embodiment the electrical unit  146  may be constructed to ignore the actuation of all pressure switches (e.g.,  206 ,  208 ) other than the switch that is actuated first in time. In another embodiment, however, the electronic unit  146  may be constructed to ignore the actuation of all pressure switches (e.g.,  206 ,  208 ) other than the switch that sets the highest power output to the cautery tip  108 . In any event, it will be appreciated based on the foregoing disclosure that the independent opening of multiple valves (e.g.,  138 ,  140 ) will increase the gas flow rate issuing from the cautery tip  108  relative to if only a single valve was opened. Alternatively, in one embodiment, instead of independent operation of buttons  114 ,  116 , the two buttons  114 ,  116  shown in  FIG. 1B  may be covered by a cover and connected together with a rocker arm (not shown) so that only one button ( 114  or  116 ) may be depressed at a time. 
         [0037]    In a further aspect, the tube  122  and electrical wire  118  extending from the handpiece  112  in  FIG. 1 a    may be integrally formed into a multilumen tubing  500 , as show for example in  FIGS. 5 and 6 . The multi-lumen tubing  500  defines a central lumen  502  for carrying the gas, and defines circumferentially spaced lumens  504  around the central lumen  502  for carrying electrical conductors  506 . The electrical conductors  506  may be bare conductors or may be insulated inside the lumens  504 . The tubing  500  is preferably constructed of an electrically insulated material. The tubing  500  may extend from a first end  508 , at the proximal end  104  of the housing  102  of the device  100 , to a second end  510  proximal of the first end  508 . The second end  510  of the tubing  500  may have terminations to connect to the fluid and electrical power supplies  516  and  522 . In one embodiment, a push-on barbed fitting  512  is inserted into the central lumen  502  and the barbed fitting  512  is connected to a tube  514  for fluid coupling to a supply of gas  516 . Also, in one embodiment, the conductors  518  extend beyond the second end  510  of the multilumen tubing  500  a certain distance and terminate in an electrical connector  520 , such as a three prong plug, for electrical coupling to a mating electrical receptacle  522 . 
         [0038]    In yet another aspect, the device  100  may include a safety switch  600  ( FIG. 6 ) that may be electrically connected in series with the electrical unit  146  to cut off power to the cautery tip  108  when the device  100  is disposed in a designated holder  700  ( FIG. 7 ) that is constructed to hold the device  100  when it is not in use (i.e., not being actively handled by a user). In one embodiment, a magnetic reed switch  600  is coupled between the electrical unit  146  and the electrical supply  120 . The magnetic reed switch  600  may be a normally closed switch that will normally energize the electrical unit  146  when it is not in the presence of a magnetic field. 
         [0039]    The holder  700  may include an elongated, open receptacle  701 , shown in  FIG. 7 , which can receive the device  100 . Also, the holder  700  may include a permanent magnet  702  mounted to the receptacle  701  so that a magnetic field may be generated by the magnet  702  inside the receptacle  701 . Preferably, the permanent magnet  702  is mounted at a position inside the receptacle  701 , such that the magnetic field will open the reed switch  600  when the device  100  is disposed in the receptacle  701 . In one embodiment, the cautery device  100  is disposed vertically or at a downward angle within the receptacle  701  with the tip  108  pointed down towards a bottom of the receptacle  701 . The magnet  702  is positioned in the receptacle  701  so that the magnet  702  is at or near the location of the reed switch  600  when the device  100  is disposed in the receptacle  701  with the tip  108  pointed down. When the device  100  is placed inside the receptacle  701 , the magnetic field generated by the magnet  702  will open the reed switch  600  and prevent closure of the activating circuits. Thus, when the device  100  is disposed in the holder, the cautery tip  108  cannot receive power and cannot heat up, which may prevent accidental fires. 
         [0040]    There have been described and illustrated herein several embodiments of a cautery device. While particular embodiments of the invention have been described, it is not intended that the invention be limited thereto, as it is intended that the invention be as broad in scope as the art will allow and that the specification be read likewise. Thus, while particular button and cautery tip arrangements have been disclosed, it will be appreciated that other button and tip arrangements may be employed as well. In addition, while a particular type of safety switch has been disclosed, it will be understood that other switches having the same or similar functionality can be used. For example, and not by way of limitation, GMR (Giant Magneto Resistive), AMR (Anisotropic Magneto Resistive), and Hall Effect switches may be used. Also, while a particular multi-lumen geometry has been disclosed, other geometries are possible. Also, while carbon dioxide may be preferred as an inert gas, it will be recognized that other gases that are non-flammable may be used. It will therefore be appreciated by those skilled in the art that yet other modifications could be made to the provided invention without deviating from its spirit and scope as claimed.