Electrosurgical devices and methods

Abstract

The present disclosure includes several electrosurgical devices and methods for sealing and transecting tissue, such as blood vessels and intestines, where tissue sealing is achieved by tissue fusion, which is performed by delivering energy to the tissue. The present disclosure also includes devices and methods for welding tissue. An exemplary device can include an elongated shaft carrying a first, fixed clamping component and a second, movable clamping component. These components can have first and second tissue-engaging surfaces and bipolar electrode devices on the tissue-engaging surfaces, respectively. Additionally, the described devices can include an energy supply source including a controller and at least one RF source for delivering electrical current, the bipolar electrode device operably connected to the controller.

Description

[Technical Field]

[0001] Priority claims

[0001] This application claims priority to U.S. Provisional Patent Application No. 63 / 381,869, filed November 1, 2022, entitled "Electrosurgical Devices and Methods," the entire contents of which are incorporated herein by reference.

[0002] FIELD OF THE INVENTION This invention relates to electrosurgical devices and methods for sealing and transecting tissue, such as blood vessels and intestines, where tissue sealing is achieved by tissue fusion, which is effected by delivering energy to the tissue. [Background technology]

[0003] Summary of the Invention [Means for solving the problem]

[0004] The present disclosure includes devices and methods for welding tissue. In one example of such a device, the device includes an elongate shaft carrying a first fixed clamping component and a second movable clamping component, each component having a first tissue-engaging surface and a second tissue-engaging surface, respectively, and a bi-polar electrode arrangement at the tissue-engaging surface.

[0005]

[0004] The devices described herein may include a controller and an energy supply source comprising at least one RF source for delivering electrical current, and the bipolar electrode device is operably connected to the controller.

[0006] The controller may be adapted to sense at least one electrical parameter of current delivery consisting of impedance, capacitance, and / or phase angle when the first and second clamping components engage tissue to sense the thickness of the engaged tissue. In another variation, the controller may be adapted to multiplex current delivery between various elements of the electrodes of opposite polarity. The controller may be adapted to adjust current delivery to the bipolar electrode device in response to a signal from at least one temperature sensor. Alternatively, the controller may be adapted to sense at least one electrical parameter of current delivery consisting of impedance, capacitance, and / or phase angle to sense effective tissue welding. The controller may further terminate current delivery when the sensed electrical parameter indicates the effective tissue welding.

[0007] In one variation of the device, the device includes a motor drive configured to move the second clamp component relative to the fixed first clamp component. The controller may be adapted to operate the motor drive to move the clamp components at variable speeds. In an additional variation, the controller is adapted to operate the motor drive to move the second clamp component at a first closing speed until the clamp components are spaced apart a selected distance, and subsequently move the second clamp component at a second closing speed to compress the tissue between the clamp components to a thickness of less than 0.5 mm (or any other range / distance, as desired). The controller may further stop movement of the second clamp component when the thickness of the engaged tissue is within a preselected range. Additionally or alternatively, the controller stops movement of the second clamp component together with the controller when the controller senses at least one electrical parameter indicating that the tissue thickness is within a preselected range. The controller may further operate the motor drive to move the clamping components apart after the controller senses at least one electrical parameter indicative of an effective tissue weld. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a cutaway perspective view of a surgical instrument according to the present invention showing a general overview of the instrument including a handle, an elongated shaft, and a working end with a bipolar electrode device. [Figure 2] 2 is a perspective view of the working end of the instrument of FIG. 1 showing a first fixed clamping member and an axially slidable second clamping member, with the outer sleeve of the shaft shown in phantom. FIG. [Figure 3]

[0009] FIG. 3 is a perspective view of an axially movable blade element separated from the shaft and first and second clamp members of FIGS. 1 and 2; [Figure 4]

[0010] 3 is a perspective view of the working end and first fixed clamp member of FIG. 2 with the axially slidable second clamp member removed to illustrate one variation of the bipolar electrode device. FIG. [Figure 5]

[0011] FIG. 10 is a perspective view of the working end and axially slidable second clamping member with the first fixed clamping member removed to show a variation of the bipolar electrode device; [Figure 6]

[0012] 6A is a schematic side view of the working end of FIG. 2 with the outer sleeve of the shaft shown in transparent view and the axially slidable second clamping member in a retracted position for capturing tissue.

[0009]

[0013] 6B is a side view of the working end of FIG. 6A with the axially slidable second clamping member in an extended position to engage and compress tissue. DETAILED DESCRIPTION OF THE INVENTION

[0010]

[0014] FIG. 1 shows an electrosurgical device 100 according to the present invention adapted to seal and transect tissue, such as hollow tubular body organs (e.g., blood vessels, intestines, and the like). Generally, electrosurgical device 100 has a handle 104 coupled to an elongated shaft assembly 105 including a distal working end 108. Distal working end 108 includes a tissue clamping assembly and a bipolar electrode arrangement 110 for engaging and applying energy to tissue. Device 100 further includes an axially movable blade assembly 112 (FIG. 2) for transecting tissue after or before sealing the tissue with the electrode arrangement.

[0011]

[0015] As seen in FIG. 1 , electrosurgical device 100 has a handle 104 including a pistol grip and an actuator or trigger 114 for actuating the device, as described further below. An elongated shaft assembly 105 extends about a longitudinal axis 115 to a working end 108 including first and second tissue clamping members 120A, 120B adapted to capture and clamp tissue under high compression. Tissue clamping members 120A and 120B are further configured to apply energy from a bipolar electrode apparatus 110 to heat weld engaged tissue. Shaft 105 of device 100 can have any suitable length and typically has a straight, rigid structure. However, curved or articulated shaft structures are also within the scope of the present invention.

[0012]

[0016] 1 and 2, shaft assembly 105 includes an outer sleeve 122 having an internal bore or passageway 124 therein. As shown in FIG. 2, first tissue clamping member 120A has a proximal portion 125 that is secured to bore 124 of outer sleeve 122 of the shaft assembly. Shaft assembly 105 and first tissue clamping member 120A are secured to one another by press fit, adhesive, welding, or the like. Typically, proximal portion 125 of first clamping member 120A is molded plastic that extends through a core 126 of a distal portion 128 of clamping member 120A. As seen in FIGS. 2, 6A, and 6B, tissue engaging surface 140A of clamping member 120A is inclined at an angle A of approximately 5° to 20° relative to longitudinal axis 115 of shaft assembly 105.

[0013]

[0017] FIG. 2 further illustrates a second movable clamp member 120B axially translatable within the bore 124 of the outer sleeve 122 of the shaft assembly 105 between a retracted position and an extended position, with FIG. 2 illustrating the second clamp member 120B in an intermediate position. FIGS. 6A and 6B illustrate the second clamp member 120B in a partially retracted position (FIG. 6A) and a fully extended position (FIG. 6B). The second clamp member 120B has a surface 140B that opposes the surface 140A of the first clamp member 120A. The second tissue-engaging surface 140B is also inclined at an angle A relative to the longitudinal axis 115 of the shaft assembly 105 to match the angle of the surface 140A of the clamp member 120A. As described further below, the tissue-engaging surfaces 140A, 140B of the clamp members 120A, 120B together carry a bipolar electrode device 110. With reference to FIG. 2, it can be seen that as the second clamping member 120B is moved toward its distal or extended position, the first and second tissue engaging surfaces 140A, 140B move toward one another to capture and clamp tissue under very high compressive forces.

[0014]

[0018] 2, 3, and 4, first clamp member 120A can be seen to have a central T-shaped channel 144 within which blade assembly 112 and cutting blade 145 are configured to move from a retracted position to an extended position and return to the retracted position to transect tissue engaged between clamp members 120A and 120B. Blade assembly 112, as shown in FIG. 3, comprises an elongated, flexible, flat metal member 146 and a distal cutting blade 145 welded thereto. Thus, central T-shaped channel 144 of first clamp member 120A is configured to receive slidable flat metal member 146 and cutting blade 145 of blade assembly 112. FIG. 3 shows blade assembly 112 in a flexed position, such as when the blade assembly is advanced through T-shaped receiving channel 144 of angled first clamp member 120A as in FIG. 2. As can be seen in Figure 2, the elongated flexible member 146 of the blade assembly must bend as it moves from a retracted position within the shaft assembly 105 toward a fully extended position within the angled first clamping member 120A. Figure 5 shows that the movable second clamping member 120B further includes a central slot 150 for receiving the cutting blade 145 of the blade assembly 112 when the first and second clamping members 120A, 120B engage and clamp the target tissue.

[0015]

[0019] FIG. 4 shows the outer sleeve 122 and first clamping member 120A with the second clamping member 120B removed. In the view of FIG. 4, the first clamping member 120A is seen to have a first polarity electrode 155A with electrode elements 156a and 156b on either side of the channel 144 that receives the cutting blade 145. The electrode elements 156a and 156b are secured to an insulator base 160, typically ceramic, by pins 158. In one variation, the ceramic is secured in place on the polymer core 126 by adhesive or, as shown in FIGS. 2 and 4, is locked in place by a metal outer sheath 162. The metal sheath 162 is adapted to strengthen the polymer core 126 of the first clamping member 120A against bending when tissue is clamped under very high pressures by distal extension of the second clamping member 120B to clamp and compress the tissue.

[0016]

[0020] FIG. 5 shows the outer sleeve 122 and movable second clamp member 120B with the first clamp member 120A removed. In FIG. 5, the second clamp member 120B can be seen to have a U-shaped, second polarity electrode 155B extending around a central slot 150 that receives the cutting blade 145 when the second clamp member 120B is moved toward its extended position. The U-shaped electrode 155B is secured to an insulator member 165 by a pin 168, which is secured to the second clamp member 120B by adhesive or other suitable means. Thus, the opposing surfaces 140A and 140B of the first and second clamp members 120A, 120B comprise a bipolar electrode device 110 connected by a cable 170 to an RF source 175 and a controller 180, as shown in FIG. 1.

[0017]

[0021] 1, device 100 carries first and second electric motors 182 and 184, as described below, connected to a power source 185 and a controller 180 via cable 170. In one variation, controller 180 is adapted to control (i) movement of second clamping member 120B from a retracted position to an extended position to clamp tissue, (ii) delivery of RF energy to electrode device 110, (iii) back and forth movement of blade assembly 112 to transect tissue, and (iv) movement of second clamping member 120B from an extended position to a retracted position to disengage welded and transected tissue.

[0018]

[0022] In FIG. 1 , handle 104 is configured with an actuator 114 adapted to rotate about pivot pin 186 to actuate the mechanisms and functions described above. In one variation, a single actuator 114, in cooperation with controller 180, can operate all of the necessary functions. Initially, actuator 114 can be actuated by pressure in the direction of arrow AA in FIG. 1 , which in turn actuates motor drive 182 to move second clamping member 120B from a retracted position to an extended position to clamp tissue between tissue engaging surfaces 140A, 140B and electrodes 155A, 155B. In this variation, motor drive 182 and rotation-to-linear mechanism 190 then axially drive drive member 188 coupled to second clamping member 120B within bore 124 of sleeve 122, as seen in FIGS. 1 and 2 . Extension of the drive member 188 and second clamp member 120B by the motor drive 182 can be stopped by a sensor mechanism that senses pressure on the drive member 188, which in turn indicates that the clamped tissue has been compressed to a selected minimum thickness. One type of sensor mechanism can include an algorithm in the controller 180 that monitors the voltage increase required to advance the second clamp member toward the extended position. The controller 180 can then determine that the target tissue compression level has been achieved, after which the controller 180 can stop the motor drive 182 and then lock the second clamp member 120B in its extended position. The controller 180 can provide an audio or visual signal to the physician that the tissue has been properly engaged and compressed. A second movement of the actuator 114 in direction AA then results in the electrodes 155A and 155B being energized, thereby delivering energy to seal or weld the engaged tissue. Determination of an optimal tissue seal may be determined by the controller 180 monitoring impedance and / or temperature from a temperature sensor (not shown) as is known in the art.After the impedance and / or temperature reach a selected level, the controller 180 can terminate energy delivery from the RF source 175 and provide an audio or visual signal. After RF energy delivery has terminated and the tissue has been welded, the physician can actuate the second motor drive 184 to actuate the actuator 114 a third time, again in direction AA, to move the cutting blade 145 from its retracted position to its extended position and back to the retracted position to transect the tissue. A drive rod 192, shown in FIGS. 1 and 2, couples the motor drive 184 and linear actuator to the blade assembly 112. The controller 180 again monitors the actuation of the cutting blade and provides an audio or visual signal that the tissue has been transected. The physician can then actuate the actuator 114 in the direction indicated by arrow BB in FIG. 1, causing the second clamping member 120B to retract from the extended position to the retracted position, disengaging from the welded and transected tissue. In this variation, the signal trigger 114 is adapted to actuate different functions of the device, although it should be understood that several different actuators may be used for each function.

[0019]

[0023] 6A and 6B show the working end 108 of the device 100 with the movable second clamping member in a partially retracted position (FIG. 6A) and a fully extended position when clamping tissue (FIG. 6B). In one variation, when engaging tissue, distal movement of the second clamping member 120B can be stopped when a selected dimension X is achieved between the surface 140A of the first member 120A and the surface 140B of the second member 120B, for example, the dimension being between 0.1 mm and 1.0 mm and selected by the physician after observing the target tissue. In that case, the controller 180 can be set to move the second clamping member 120B to clamp tissue up to the selected dimension X. The travel of the axially movable second clamping member 120B between the fully retracted and extended positions is between 1 cm and 10 cm. The dimension X between and perpendicular to the first and second tissue engaging surfaces 140A, 140B in the retracted position, Fig. 6A, is at least 2 mm. The dimension X between the first and second tissue engaging surfaces 140A, 140B in the extended position, Fig. 6B, is less than 1.0 mm.

[0020]

[0024] In one variation, the controller 180 can include a mechanism that allows movement of the blade assembly 112 to occur only when the second, movable clamping member 120B is extended to a position suitable for clamping and compressing tissue. In another variation, a single actuation of the trigger 114 can cause the controller 180 to sequentially perform all of the above-listed steps of clamping, welding, and transecting tissue.

[0021]

[0025] In another variation, a rotatable adjustment knob or grip 195 may be provided on the proximal surface of the handle 104 that allows the physician to adjust the target dimension X between the first tissue engaging surface 140A and the second tissue engaging surface 140B, as shown in FIG. 6B.

[0022]

[0026] In other variations of the tissue clamping assembly, energy delivery for tissue welding may be provided by a resistive heating element, an inductive heating element, an ultrasonic transducer, a light energy emitter, etc. Additionally, a circular stapling mechanism may be provided in the clamping assembly in combination with a thermal welding mechanism as described above, as is known in the art.

[0023]

[0027] While specific embodiments of the present invention have been described in detail above, it will be understood that this description is for illustrative purposes only and that the above description of the present invention is not exhaustive. Certain features of the invention may be shown in some drawings and not in others; this is for convenience only, and any feature may be combined with other features in accordance with the present invention. Many variations and alternatives will be apparent to those skilled in the art. Such alternatives and variations are intended to be included within the scope of the claims. Particular features set forth in dependent claims may be combined and fall within the scope of the invention. The present invention further encompasses embodiments as if the dependent claims were alternatively recited in multiple dependent claim format with reference to other independent claims.

[0024]

[0028] Other variations are within the spirit of the invention. Accordingly, while the invention is susceptible to various modifications and alternative constructions, specific illustrative embodiments thereof are shown in the drawings and have been described above in detail. It is to be understood, however, that there is no intention to limit the invention to the particular form or forms disclosed, but on the contrary, the invention covers all modifications, alternative constructions, and equivalents falling within the spirit and scope of the invention as defined in the appended claims.

[0025]

[0029] All references, including publications, patent applications, and patents, cited in this specification are herein incorporated by reference to the same extent as if each individual reference was individually and specifically indicated to be incorporated by reference and was set forth in its entirety herein.

Claims

1. 1. An electrosurgical instrument comprising: a handle coupled to an elongated shaft having a longitudinal axis; the elongate shaft comprising a first member including a first tissue engaging surface having a first fixed angle relative to the longitudinal axis and a second member including a second tissue engaging surface having a second fixed angle relative to the longitudinal axis, the first member being disposed at a distal end of the elongate shaft and the second member being axially movable; a mechanism for moving the second member between a retracted position and an extended position, wherein the retracted position has an increased spacing between the first and second tissue engaging surfaces for capturing tissue, and the extended position has a decreased spacing between the first and second tissue engaging surfaces for clamping tissue; and a first bipolar electrode and a second bipolar electrode disposed in spaced apart relationship on the first tissue engaging surface and the second tissue engaging surface; 1. An electrosurgical instrument comprising:

2. 10. The electrosurgical instrument of claim 1, The electrosurgical instrument, wherein the first fixed angle is between 5° and 20°.

3. 10. The electrosurgical instrument of claim 1, The electrosurgical instrument, wherein the second fixed angle is between 5° and 20°.

4. 10. The electrosurgical instrument of claim 1, The electrosurgical instrument, wherein the second member has a stroke of between 1 cm and 10 cm when moved axially between the retracted position and the extended position.

5. 10. The electrosurgical instrument of claim 1, An electrosurgical instrument wherein a dimension between and perpendicular to the first and second tissue engaging surfaces in the retracted position is at least 2 mm.

6. 10. The electrosurgical instrument of claim 1, An electrosurgical instrument wherein a dimension between and perpendicular to the first and second tissue engaging surfaces in the extended position is less than 1.0 mm.

7. 10. The electrosurgical instrument of claim 1, An electrosurgical instrument wherein the first and second tissue engaging surfaces carry electrodes of opposite polarity.

8. 10. The electrosurgical instrument of claim 1, The electrosurgical instrument, wherein the second member is axially movable between the retracted position and the extended position by a motor drive.

9. 10. The electrosurgical instrument of claim 1, The electrosurgical instrument further comprising an axially movable blade assembly adapted to move axially within the first and second members between retracted and extended positions.

10. 10. The electrosurgical instrument of claim 9, The electrosurgical instrument, wherein the axially movable blade assembly is moved between the retracted and extended positions by a motor drive.

11. 10. The electrosurgical instrument of claim 9, An electrosurgical instrument wherein the axially movable blade assembly includes a cutting blade element slidable within a channel of the first member.

12. 10. The electrosurgical instrument of claim 9, An electrosurgical instrument wherein the axially movable blade assembly includes an elongated flexible element extending within the elongated shaft.

Images