Laparoscopic apparatus for performing electrosurgical procedures

[0001] 1. Technical Field

[0002] The present disclosure relates generally to an apparatus and method for performing laparoscopic electrosurgical procedures, and more particularly, to an apparatus for controlling suction and irrigation cycles during laparoscopic electrosurgical procedures.

[0003] 2. Background of Related Art

[0004] During electrosurgery, a source or active electrode delivers energy, such as radio frequency (RF) energy, from an electrosurgical generator to a patient and a return electrode or a plurality thereof carry current back to the electrosurgical generator. In monopolar electrosurgery, the source electrode is typically a hand-held instrument placed by the surgeon at the surgical site and the high current density flow at this electrode creates the desired surgical effect of ablating, cutting or coagulating tissue. The patient return electrodes are placed at a remote site from the source electrode and are typically in the form of pads adhesively adhered to the patient.

[0005] Bipolar electrosurgery is conventionally practiced using electrosurgical forceps-type device, where the active and return electrodes are housed within opposing forceps' jaws. The return electrode is placed in close proximity to the active (i.e., current supplying) electrode such that an electrical circuit is formed between the two electrodes (e.g., electrosurgical forceps). In this manner, the applied electrical current is limited to the body tissue positioned between the electrodes.

[0006] During electrosurgical procedures, byproducts form at the surgical site from coagulated and/or cut flesh (e.g., debris, smoke, etc.). This debris may be removed by irrigating the site, where an irrigation fluid is supplied to the surgical site and then withdrawn through suction. Conventional irrigation mechanisms have been controlled mechanically with the mechanical controls disposed within a handle holding the electrosurgical instrument. Such designs could not achieve a desired level of suction and/or irrigation and moreover, these designs were not compact and ergonomic.

[0007] Therefore, there is a need for an electrosurgical apparatus having an irrigation system controlled through electrical means and disposed outside the apparatus' handle.

[0008] The present disclosure provides for a system and apparatus for irrigating a surgical site during an electrosurgical procedure. The system includes a hand piece for controlling an electrosurgical generator and an irrigation system having an irrigation tube for supplying irrigation fluid and a suction tube for withdrawing irrigation fluid and smoke. The hand piece's controls are connected to a hardware module which controls irrigation and suction valves disposed within a valve cassette which adjusts the flow of the irrigation fluid and suction. In addition, the irrigation fluid is used to cool the electrode.

[0009] According to one embodiment of the present disclosure, a system for irrigating a surgical site during an electrosurgical procedure is provided. The system includes a hand piece having an elongated housing connected to a multilumen tube extending proximally from the housing and having an irrigation tube for delivering irrigation fluid, a suction tube for withdrawing irrigation fluid, and electrical wiring, the hand piece further includes first controls for adjusting flow of irrigation fluid within the irrigation tube and second controls for adjusting flow of irrigation fluid within the suction tube, the first and second controls transmitting first and second control signals through the electrical wiring; a valve cassette connected to the multilumen tube, the cassette including an irrigation valve configured to control the flow within the irrigation tube and a suction valve configured to control the flow within the suction tube, the irrigation tube further connected to an irrigation fluid source and the suction tube further connected to a vacuum source; and a hardware control module connected to the electrical wiring for receiving the first and second control signals and controlling the irrigation valve through an irrigation servo actuator based on the first control signals and controlling the suction valve through a suction servo actuator based on the second control signals.

[0010] According to another embodiment of the present disclosure, an apparatus for controlling irrigation at a surgical site during an electrosurgical procedure is provided. The apparatus includes an elongated housing, a multilumen tube extending proximally from the housing and having an irrigation tube for delivering irrigation fluid including an irrigation check valve, a suction tube for withdrawing irrigation fluid including a suction check valve, and electrical wiring, first and second controls configured for adjusting flow of irrigation fluid within the irrigation tube and for adjusting suction within the suction tube respectively, the first and second controls transmitting first and second control signals, the multilumen tube connected to a valve cassette, the cassette including an irrigation valve configured to control the flow within the irrigation tube and a suction valve configured to control the flow within the suction tube, the irrigation tube further connected to an irrigation fluid source and the suction tube further connected to a vacuum source, and a hardware control module configured to receive the first and second control signals and controlling the irrigation valve through an irrigation servo actuator based on the first control signals and controlling the suction valve through a suction servo actuator based on the second control signals.

[0023] Embodiments of the present disclosure are described below with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail to avoid obscuring the present disclosure in unnecessary detail.

[0024] The foregoing disclosure describes embodiments with reference to a monopolar laparoscopic surgical instrument. However, principles of the present disclosure may be utilized in a bipolar instrument as well as suitable open instruments.

[0025] An electrosurgical system and method to be used to perform cautery procedures, hemostatis, and other suitable procedures are provided. The system provides irrigation and/or suction (e.g., a vacuum line), which may be performed contemporaneously with the electrosurgical procedure or after the procedure is complete. In some embodiment, the irrigation fluid may be used to cool the electrosurgical cautery electrode to reduce eschar build-up, modify tissue effect, and/or prevent inadvertent burns from a heated electrode.

[0026] Embodiments of the presently disclosed electrosurgical system will now be described in detail with reference to the drawings wherein like reference numerals identify similar or identical elements. As used herein, the term “distal” refers to that portion that is further from the user while the term “proximal” refers to that portion that is closer to the user.

[0027] FIG. 1 shows an electrosurgical system including a generator 10, a hand piece 12 (e.g., an electrosurgical pencil) having an active electrode 14 at a distal end thereof which is brought in contact with a patient P to effect a cut and/or coagulation procedure depending upon the selected operating mode. The active electrode 14 is an electrically conducting element that 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 14 may include an elongated narrow cylindrical needle which is solid or hollow with a flat, rounded, pointed or slanted distal end.

[0028] Attached to the patient P is a return electrode 16 that returns the electrosurgical current from the patient P to the generator 10. The hand piece 12 is coupled to the generator 10 via a multilumen tube 18 extending from a proximal end of the hand piece 12. In one embodiment, the multilumen tube 18 includes electrical wires for supplying the electrosurgical energy to the active electrode 14 as well as electrical power for the controls of the hand piece 12.

[0029] The active electrode 14 may be used laparoscopically, e.g., inserted into a body cavity through a percutaneous incision. To accomplish this, the electrode 14 may be introduced into a body cavity through a suitable trocar (not shown). The trocar may include an elongated tube that penetrates the body cavity with its distal end and the electrode 14 is introduced thereto through its proximal end. In addition, the trocar may include a hemostatic valve disposed at its proximal end to prevent backflow of gases.

[0030] The hand piece 12 also includes an irrigation tip that irrigates the surgical site, the details of which will be described below. Other components of the irrigation system, such as irrigation fluid supply and valve mechanisms may be disposed within the generator 10 or within a separate stand-alone device such as a suitable cassette. The irrigation and suction lines are coupled from the irrigation system to the hand piece 12 and thereafter to the irrigation tip and may be included within the multilumen tube 18.

[0031] The irrigation system supplies a suitable irrigation fluid such as a saline solution, through the irrigation tip near the active electrode 14. The irrigation fluid is used to cool the active electrode 14 during electrosurgical usage to reduce or eliminate eschar (e.g., sloughed-off dead tissue caused by a burn or cauterization). In addition, the irrigation fluid may be used to remove any debris caused by the electrosurgical procedure.

[0032] The hand piece 12 remains outside the body cavity and outside the trocar and allows the surgeon to control the electrosurgical operations as well as irrigation cycles. Referring to FIG. 2A, the hand piece 12 according to one embodiment of the disclosure is shown and includes a variety of controls within an elongated housing 19. The hand piece 12 includes mode selection controls 20 that allow the surgeon to select the operating mode for the generator 10 (e.g., cut, coagulation, blend). Generally, generators operate in a plurality of modes, e.g., cut, coagulation, or blend, accomplished by using different current waveforms. Using a constant waveform, a generator allows a surgeon to vaporize or cut tissue since a constant waveform produces heat very rapidly. Using an intermittent waveform causes a generator's duty cycle to be reduced to coagulate tissue. A blended current allows for a mixture of the two above waveforms to achieve intermediate results. The hand piece 12 also includes intensity controls 22 that allow the surgeon to modify the power of the energy being supplied to the active electrode 14, which is supported within the housing 19 and extends distally therefrom.

[0033] The hand piece 12 also includes controls for adjusting the irrigation system. More specifically, the hand piece 12 may include an irrigation controller 24 which activates and deactivates the flow of the irrigation fluid and an irrigation volume adjuster 26 which adjusts the flow volume of the irrigation fluid. In addition, the hand piece 12 includes a suction control 28 which activates and deactivates vacuum suction apparatus to withdraw the aspirated irrigation fluid. A suction volume adjuster 30 controls a setting level of the vacuum pump which controls the rate at which irrigation fluid is withdrawn.

[0034] The mode selection controls 20, intensity controls 22, irrigation volume adjuster 26 and suction volume adjuster 30 are operatively connected to a voltage divider network (“VDN”) (e.g., a film-type potentiometer). For the purposes herein, the term “voltage divider network” relates to any suitable form of resistive, capacitive or inductive circuit that determines the output voltage across a voltage source (e.g., one of two impedances) connected in series. A “voltage divider” as used herein relates to a number of resistors connected in series which are provided with taps at certain points to make available a fixed or variable fraction of the applied voltage. An example of a hand piece employing such a voltage divider is discussed in a commonly-owned U.S. patent application Ser. No. 10/718,113 entitled “Electrosurgical Pencil With Improved Controls,” which is hereby incorporated by reference in its entirety. It is also envisioned that the irrigation volume adjuster 26 and suction volume adjuster 30 divider networks may be aligned with a single slide (not explicitly shown) wherein moving of the slide in one direction adjusts flow of irrigation fluid and moving the slide in another direction adjusts flow of aspirated irrigation fluid.

[0035] The multilumen tube 18 extends proximally from the housing 19 and includes multiple lumens containing conduits for electrical wiring 36, an irrigation tube 32 that supplies the irrigation fluid to a surgical site, and suction tube 34 that withdraws the irrigation fluid by providing a conduit to a suitable vacuum source. The electrical wiring 36 includes wires for transmitting electrosurgical current to the active electrode 14 and control current for transmitting input signals from the controls of the hand piece 12. Using DC voltage to transmit input signals is well known in the art and is described in commonly owned U.S. Pat. Nos. 3,699,967 and 3,801,800, both of which are hereby incorporated by reference in their entirety.

[0036] As shown in FIG. 2B, an irrigation check valve 31 and a suction check valve 33 are disposed within the irrigation tube 32 and the suction tube 34, respectively, at the proximal end of the hand piece 12. The suction check valve 33 may be of “duck bill” design or in some embodiment may be a flap. Orientation of the suction check valve 33 allows fluids and vacuum to flow with minimum resistance therethrough but prevents fluid from draining in the opposing direction.

[0037] The irrigation check valve 31 may also be of “duck bill” design, as well as, a poppet, a flap, a spring-loaded ball type check valve, or any suitable check valve that may be inserted modularly into the irrigation tube. The irrigation check valve 31 is configured to open under sufficient opening pressure to allow for irrigation fluid to flow therethrough. Opening pressure from about 6 inches to about 48 inches of water column pressure is sufficient to prevent fluid in the irrigation tube 32 from draining through the hand piece 12 when an irrigation valve 42 is closed (see FIG. 3). The pressure is also sufficient to provide minimum resistance to flow pressure when the irrigation valve 42 is open.

[0038] With reference to FIG. 3, the multilumen tube 18 couples the hand piece 12 to a valve cassette 40 that includes suitable mechanisms for controlling the in-flow and out-flow of the irrigation fluid at the surgical site. The electrical wiring 36 is coupled to a contact block 38 which provides an electrical interface between the hand piece 12 and the generator 10. More specifically, the contact block 38 is electrically coupled to a hardware control module 50 that monitors and controls the operation of the generator 10 and the valve cassette 40. The control module 50 may include electronic circuitry such as a microprocessor, memory, and comparators for performing a variety of functions within the purview of those skilled in the art (e.g., comparing values, receiving control signals, converting analog signals to and from digital signals, issuing control commands to generator 10 and valve cassette 40, etc.).

[0039] The valve cassette 40 includes a suction valve 44 which controls vacuum within the suction tube 34. Opening the suction valve 44 creates vacuum within the suction tube 34 by providing access to a vacuum pump (not explicitly shown) thereby leading to siphoning off of the aspirated irrigation fluid. Closing the suction valve 44 terminates access to the vacuum pump. Regulating the position of the suction valve 44 allows the surgeon to modulate the amount of suction.

[0040] The suction valve 44 may be regulated by a vacuum servo actuator 45 that opens and closes the valves based on control signals from the control module 50. The control signals originate from the suction control 28 and the suction volume adjuster 30 and are transmitted to the control module 50 along the electrical wiring 36 and through the contact block 38.

[0041] The valve cassette 40 also includes the irrigation valve 42 that adjusts the aperture of the irrigation tube 36, thereby adjusting the flow of the irrigation fluid to the surgical site. The irrigation valve 42 may be controlled by an irrigation servo actuator 43 receives control signals from the control module 50. The irrigation fluid may be dispensed from a pressurized bag 46 that may be compressed by a servo regulator 48 (e.g., an air supply pump).

[0042] In one embodiment, flow of the irrigation fluid is regulated in the following manner. Initially, the surgeon selects desired pressure for supplying the irrigation fluid. Thereafter, control signals are transmitted from the irrigation controller 24 and the irrigation volume adjuster 26 through the electrical wiring 36 and the contact block 38. The desired flow/pressure may be achieved by increasing pressure on the pressurized bag 46 and leaving the irrigation valve 42 open. Alternatively, the pressure on the pressurized bag 46 may remain static and the irrigation valve 42 may be adjusted to achieve the desired flow rate. Those skilled in the art will appreciate that irrigation fluid may be stored in a variety of containers (e.g., a storage tank) and be dispensed using a pump. The pump may be controlled by varying the pump's pressure between zero and maximum setting, e.g., a variable speed pump. The irrigation volume adjuster 26 includes a VDN may delivers a control voltage to the pump varying its output pressure.

[0043] FIGS. 4A-C show the active electrode 14 with an irrigation tip 56. The active electrode 14 is bent into an L-shaped configuration. However, the electrode 14 may be in a variety of suitable shapes and configurations (e.g., spatula, needle, ball-point, solid, hollow, etc.). The active electrode 14 is positioned between an irrigation opening 52 and a suction opening 54 as shown in FIGS. 4A-C. In one embodiment, the irrigation tip 56 is made from an insulative material to prevent accidental shock to the patient.

[0044] It is envisioned that during an electrosurgical procedure the irrigation fluid passes through the irrigation opening 52 and into the surgical site to wash away any debris generated during the surgical procedure. The irrigation fluid is then suctioned off through the suction opening 54 to evacuate the debris from the surgical site. In addition, the smoke generated during the procedure is also evacuated. The irrigation tip 56 may have a plurality of irrigation openings 52 and suction openings 54.

[0045] The present invention also contemplates that the irrigation fluid is used to cool the active electrode 14 in order to maintain the tip of the electrode 14 at a temperature below that of eschar formation (e.g., 100° C.). The active electrode 14 may include specific geometry that improves heat transfer from the surface of the active electrode 14 to the irrigation fluid (e.g., grooves chiseled therein). To achieve efficient heat transfer from the active electrode 14, the irrigation fluid may be passed at a sufficiently slow rate so that the fluid flows along the active electrode 14 via capillary action and into the suction opening 54. The irrigation and suction openings 52, 54 extend for the same distance longitudinally to accommodate for irrigation of the active electrode 14.

[0046] It is also envisioned that the suction opening 54 may extend further than the irrigation opening 52. This arrangement allows the irrigation fluid to flow along a larger segment of the active electrode 14 than an arrangement where the irrigation and suction paths are approximately the same length. As a result, the active electrode 14 transfers more heat to the irrigation fluid. Such additional cooling may be utilized in electrosurgical procedures that have higher energy requirements, since such procedures generate more heat and require more cooling to alleviate eschar formation. In addition, extending the suction opening 54 allows for irrigation fluid to be jetted beyond the active electrode 14 allowing for better irrigation of the surgical site.

[0047] FIGS. 5A-B show another embodiment of the active electrode 14 and the irrigation tip 56, where the active electrode 14 is positioned above the irrigation and suction openings 52, 54. This arrangement may be particularly useful where cooling of the electrode 14 is secondary to providing proper irrigation and evacuation of the debris and smoke from the surgical site. As shown in FIG. 5B, the irrigation opening 52 includes a lip 53 to direct the flow of the irrigation fluid downward and into the surgical site, which allows for rapid irrigation of the surgical site.

[0048] FIGS. 6A-B show an irrigation adapter 58 without the active electrode 14. The irrigation adapter 58 includes an irrigation opening 60 and a front suction opening 64. The irrigation adapter 58 may include a ball 63 serving a ball valve 65, such as when the suction is on or the irrigation adapter 58 is pressed against a surface (e.g., tissue) the ball 63 retracts to allow for irrigation fluid to pass through the front suction opening 64. In addition, the irrigation adapter 58 also includes one or more side suction opening 62.

[0049] FIG. 6B shows a cross sectional view of the irrigation adapter 58 and its connectivity to the irrigation tube 32 and the suction tube 34. The irrigation fluid enters the irrigation adapter 58 through an irrigation passage 66 and flows through an irrigation channel 70 of the irrigation adapter 58. The irrigation fluid is extracted through a suction channel 72 and enters the suction tube 34 through a suction passage 68. The suction passage 72 extends further than the irrigation passage 70 to allow for separated and distinct in and out flow paths.

[0050] The irrigation adapter 58 is coupled to the irrigation and suction tubes by a plurality of ridges 74, 76, 78, 80. The ridges 74, 76 are in contact with the top and bottom outside surfaces of the suction passage 68 and the ridges 78, 80 are in contact with the top outside surface of the irrigation passage 70 and the suction passage 80, respectively. In effect, the ridges 78, 80 secure the entire irrigation adapter 58, while the ridges 78, 80 provide additional support to the suction passage 72 that extends beyond the length of the irrigation passage 70.

[0051] It is envisioned that the irrigation and suction system of the present disclosure may be utilized as a stand-alone system (e.g., not part of an electrosurgical apparatus). The described embodiments of the present disclosure are intended to be illustrative rather than restrictive, and are not intended to represent every embodiment of the present disclosure. Various modifications and variations can be made without departing from the spirit or scope of the disclosure as set forth in the following claims both literally and in equivalents recognized in law.