The present disclosure relates to surgical instruments and, more particularly, to anti-backdrive mechanisms for vessel sealing instruments configured to maintain closure pressure during sealing.
A surgical forceps is a pliers-like surgical instrument that relies on mechanical action between its jaw members to grasp, clamp, and constrict tissue. Electrosurgical forceps utilize both mechanical clamping action and energy to heat tissue to treat, e.g., coagulate, cauterize, or seal, tissue. Typically, once tissue is grasped under a closure pressure suitable to seal vessels or tissue, the actuation mechanism (e.g., handle) is locked during the delivery of electrosurgical energy to produce a seal. In some instance the surgeon holds the actuation mechanism during electrosurgical activation. During sealing, the tissue naturally expands against the closure pressure which, in some instances, can affect the resulting tissue seal as the closure pressure no longer falls within a particular closure pressure range.
Accordingly, there exists a need to maintain the closure pressure within the desired closure pressure range during the sealing process.
As used herein, the term “distal” refers to the portion that is being described which is further from a user, while the term “proximal” refers to the portion that is being described which is closer to a user. Further, to the extent consistent, any or all of the aspects detailed herein may be used in conjunction with any or all of the other aspects detailed herein.
Provided in accordance with aspects of the present disclosure is a vessel sealing instrument including a housing having a shaft extending from a distal end thereof. A distal end of the shaft includes an end effector assembly having a pair of opposing first and second jaw members operably coupled thereto. One or both of the first or second jaw members is movable between an open position and a closed position for clamping tissue with a closure pressure within the range of about 3 kg/cm2 to about 16 kg/cm2. One or both of the first or second jaw members is adapted to connect to a generator configured to provide electrosurgical energy thereto in accordance with a sealing algorithm upon activation thereof.
An anti-backdrive mechanism is operably associated with the end effector assembly and includes first and second mesh-like electrodes disposed in opposing relation on respective first and second jaw members. The first and second mesh-like electrodes include openings defined therein. The first and second mesh-like electrodes are compressible between a first configuration for grasping tissue under a grasping pressure wherein the openings defined within each mesh-like electrode include a first size to a second configuration for sealing tissue within the closure pressure wherein the openings defined within each mesh-like electrode expand to a second size configured to release steam upon activation of the mesh-like electrode to seal tissue.
In aspects according to the present disclosure, upon return of the first and second jaw members to the open position, the mesh-like electrodes return to the first configuration. In other aspects according to the present disclosure, upon return of the first and second jaw members to the open position, the mesh-like electrodes return to the first configuration under a spring bias.
In aspects according to the present disclosure, electrosurgical energy is provided to the mesh-like electrodes when the mesh-like electrodes are disposed in the second configuration. In aspects according to the present disclosure, electrosurgical energy is provided to the mesh-like electrodes prior to the mesh-like electrodes transitioning to the second configuration.
In aspects according to the present disclosure, in the first configuration a grasping area is defined between the mesh-like electrodes for initially grasping tissue and wherein during transition to the second configuration, the mesh-like electrodes expand along the tissue to form a larger area therebetween for sealing tissue.
In aspects according to the present disclosure, a gap defined between the mesh-like electrodes when disposed in the second configuration is within the range of about 0.001 inches to about 0.006 inches. In other aspects according to the present disclosure, the gap defined between the mesh-like electrodes during sealing is maintained within the range of about 0.001 inches to about 0.006 inches. In still other aspects according to the present disclosure, the gap defined between the mesh-like electrodes remains the same during sealing.
Provided in accordance with aspects of the present disclosure is a vessel sealing instrument including a housing having a shaft extending from a distal end thereof. A distal end of the shaft includes an end effector assembly having a pair of opposing first and second jaw members operably coupled thereto. One or both of the first or second jaw members is movable between an open position wherein the jaw members are spaced relative to one another and a closed position for clamping tissue with a closure pressure within the range of about 3 kg/cm2 to about 16 kg/cm2 and a gap distance defined between the jaw members of about 0.001 inches to about 0.006 inches. One or both of the first or second jaw members is adapted to connect to a generator configured to provide electrosurgical energy thereto in accordance with a sealing algorithm upon activation thereof.
An anti-backdrive mechanism is operably associated with the end effector assembly, and includes first and second mesh-like electrodes disposed in opposing relation on respective first and second jaw members. The first and second mesh-like electrodes including openings defined therein. The first and second mesh-like electrodes are compressible between a first configuration for grasping tissue under a grasping pressure wherein the openings defined within each mesh-like electrode include a first shape, e.g., diameter, to a second configuration for sealing tissue within the closure pressure wherein the openings defined within each mesh-like electrode expand to a second shape, e.g., diameter, configured to release steam upon activation of the mesh-like electrode to maintain the jaw members within the gap distance for sealing tissue.
In aspects according to the present disclosure, the orientation of the mesh may increase seal strength, e.g., relieve stress concentrations and help denature the tissue, e.g., cross-diagonal pattern normal to the tissue.
In aspects according to the present disclosure, upon return of the first and second jaw members to the open position, the mesh-like electrodes return to the first configuration. In other aspects according to the present disclosure, upon return of the first and second jaw members to the open position, the mesh-like electrodes return to the first configuration under a spring bias.
In aspects according to the present disclosure, electrosurgical energy is provided to the mesh-like electrodes when the mesh-like electrodes are disposed in the second configuration. In aspects according to the present disclosure, electrosurgical energy is provided to the mesh-like electrodes prior to the mesh-like electrodes transitioning to the second configuration.
In aspects according to the present disclosure, in the first configuration a grasping area is defined between the mesh-like electrodes for initially grasping tissue and wherein during transition to the second configuration, the mesh-like electrodes expand along the tissue to form a larger area therebetween for sealing tissue.
In aspects according to the present disclosure, wherein the gap defined between the mesh-like electrodes during sealing is maintained within the range of about 0.001 inches to about 0.006 inches. In other aspects according to the present disclosure, the gap defined between the mesh-like electrodes remains the same during sealing.
The above and other aspects and features of the present disclosure will become more apparent in view of the following detailed description when taken in conjunction with the accompanying drawings wherein like reference numerals identify similar or identical elements.
Referring to
Forceps 10 further includes a shaft 12 having a distal end portion 14 configured to engage (directly or indirectly) end effector assembly 100 and a proximal end portion 16 that engages (directly or indirectly) housing 20. Rotating assembly 60 is rotatable in either direction to rotate shaft 12 and end effector assembly 100 relative to housing 20 in either direction. Housing 20 houses the internal working components of forceps 10.
An electrosurgical cable 300 connects forceps 10 to an electrosurgical generator “G” or other suitable energy source, although forceps 10 may alternatively be configured as a handheld instrument incorporating energy-generating and/or power components thereon or therein. Cable 300 includes wires (not shown) extending therethrough, into housing 20, and through shaft 12, to ultimately connect electrosurgical generator “G” to jaw member 110 and/or jaw member 120 of end effector assembly 100. Activation button 92 of activation assembly 90 is disposed on housing 20 are electrically coupled between end effector assembly 100 and cable 300 to enable the selective supply of energy to jaw member 110 and/or jaw member 120, e.g., upon activation of activation button 92. However, other suitable electrical connections and/or configurations for supplying electrosurgical energy to jaw member 110 and/or jaw member 120 may alternatively be provided, as may other suitable forms of energy, e.g., ultrasonic energy, microwave energy, light energy, thermal energy, etc.
Forceps 10 additionally includes a knife assembly 170 (
With additional reference to
Each jaw member 110, 120 of end effector assembly 100 includes an electrically-conductive tissue-contacting surface 116, 126. Tissue-contacting surfaces 116 are positioned to oppose one another for grasping and treating tissue. More specifically, tissue-contacting surfaces 116, 126 are electrically coupled to the generator “G,” e.g., via cable 300, and activation button 92 to enable the selective supply of energy thereto for conduction through tissue grasped therebetween, e.g., upon activation of activation button 92. One or both of tissue-contacting surfaces 116, 126 may include one or more stop members 115 extending therefrom to define a minimum gap distance between electrically-conductive tissue-contacting surfaces 116, 126 in the approximated position of jaw members 110, 120, facilitate grasping of tissue, and/or inhibit shorting between electrically-conductive tissue-contacting surfaces 116, 126.
The stop member(s) 115 may be formed at least partially from an electrically-insulative material or may be effectively insulative by electrically isolating the stop member(s) from one or both of the electrically-conductive tissue-contacting surfaces 116, 126. The one or more stop members 115 may be disposed on one or both jaw members 110, 120 or on the tissue-contacting surfaces 116, 126 and are configured to regulate the distance therebetween. Details relating to various stop member designs are disclosed in U.S. Pat. No. 7,857,812, 10,687,887 the entire contents of each of which being incorporated by reference here. Ranges between about 0.001 inches to about 0.006 inches are contemplated.
A pivot pin 103 of end effector assembly 100 extends transversely through aligned apertures defined within jaw members 110, 120 and shaft 12 to pivotably couple jaw member 110 to jaw member 120 and shaft 12. A cam pin 105 of end effector assembly 100 extends transversely through cam slots defined within jaw members 110, 120 and is operably engaged with a distal end portion of a drive bar 152 (
More specifically, distal translation of cam pin 105 relative to jaw members 110, 120 urges cam pin 105 distally through the cam slots to thereby pivot jaw members 110, 120 from the spaced-apart position towards the approximated position, although cam slots may alternatively be configured such that proximal translation of cam pin 105 pivots jaw members 110, 120 from the spaced-apart position towards the approximated position. One suitable drive assembly is described in greater detail, for example, in U.S. Pat. No. 9,655,673, the entire contents of which are hereby incorporated herein by reference.
Referring to
A biasing spring (not shown) associated with movable handle 40 and/or the drive assembly may be provided to bias jaw members 110, 120 towards a desired position, e.g., the spaced-apart position or the approximated position. Various drive assemblies are shown and described in any one of the above-identified commonly-owned U.S. Patents referenced herein.
Fixed handle 50 operably supports activation button 92 of activation assembly 90 thereon in an in-line position, wherein activation button 92 is disposed in the actuation path of movable handle 40. In this manner, upon pivoting of movable handle 40 relative to fixed handle 50 from the actuated position to an activated position, protrusion 94 of movable handle 40 is urged into contact with activation button 92 to thereby activate activation button 92 and initiate the supply of energy to electrically-conductive surfaces 116, 126, e.g., to treat tissue grasped therebetween. Alternatively, actuation button 92 may be disposed in any other suitable position, on housing 20 or remote therefrom, to facilitate manual activation by a user to initiate the supply of energy to electrically-conductive surfaces 116, 126.
With reference to
Referring to
As mentioned above, pivoting of movable handle 40 relative to fixed handle 50 from an un-actuated position towards an actuated position pivots jaw members 110, 120 from the spaced-apart position towards the approximated position for grasping tissue therebetween. When fully grasped, the drive assembly 301 is configured to initially generate a closure pressure suitable for sealing vessels upon activation of electrosurgical energy from generator “G”. Maintaining closure pressures within the range of about 3 Kg/cm2 to about 16 Kg/cm2 are known to promote quality seals.
With in-line actuation instruments, the surgeon is typically required to maintain the handle 40 in position to continually maintain the closure pressure. For example and as shown in
Other forceps e.g., forceps 10′ of
After the initial closure pressure within the above-identified range is generated and the jaw members 110, 120 (or 110′, 120′) are clamped on a vessel or on tissue, the forceps 10 (10′) is ready for activation. As mentioned above, during sealing the vessel or tissue expands against the jaw members, e.g., jaw members 110′, 120′, which may reduce the actual closure pressure during formation of the seal. If the closure pressure falls outside of the above-noted range, the seal may not be as effective.
Upon pressure “P” being applied between jaw members 410, 420 to seal tissue “T”, the mesh-like electrodes 412, 422 compress onto the tissue “T” expanding therealong forming a seal area “S” therebetween. In other words, as the jaw members 410, 420 are actuated to compress tissue within the grasping area “GA”, the grasping area “GA” expands eventually forming a larger area “S” for sealing tissue (
As can be appreciated and as described above, during sealing, the tissue “T” melts and reforms into a homogenous fused mass with limited demarcation between opposing tissue structures, e.g., opposing walls of a vessel. Typically, during the sealing process, the tissue “T” expands and lets off steam creating opposing pressure against the closing pressure “P” of the jaw members 410, 420. Additional pressure may be created as the tissue “T” reforms and rehydrates. As mentioned above, it is important to maintain the sealing pressure and gap within the above-identified range during the entire sealing process to insure a proper tissue seal. The backdrive assembly 450 including the mesh-like electrodes 412, 422 of the present disclosure is configured to accomplish this purpose.
More particularly, during closure of the jaw members 410, 420 about tissue “T” the compression of the mesh-like electrodes 412, 422 onto the tissue “T” and the expansion of the openings 413 thereof create an avenue of release for the build-up of steam “ST” along the tissue seal “S” relieving the build-up of pressure between the jaw members 410, 420 and maintaining the jaw members 410, 420 within the appropriate sealing pressure range and gap distance range to form a consistent tissue seal “S”. Upon release of the tissue “T”, the expanded mesh-like electrodes 412, 422 and openings 413 shown in
It is contemplated that the presently designed anti-backdrive assembly 450 may be particularly well-suited for sealing tissue utilizing a so-called “slow close” sealing system, algorithm or methodology wherein when the jaw members 410, 420 are approximated from an open or grasping position to the sealing position (e.g., jaw members 410, 420 closed about tissue within the above-identified gap range) the jaw members 410, 420 are continually energized according to the sealing algorithm. This is in contrast to more traditional tissue sealing wherein the jaw members 410, 420 are fully approximated and then energized to seal tissue.
With the slow close method, the gradual expansion of the openings 413 may be regulated with the closure of the jaw members 410, 420 according to an automated or robotic surgical procedure to insure a consistent and quality tissue seal “S”. This technique may help regulate pressure between the jaw members 410, 420. Various slow close methodologies, systems and algorithms are disclosed in U.S. Pat. No. 8,357,160 entitled “System and Method for Controlling Electrode Gap During Tissue Sealing”, the entire contents of which being incorporated by reference herein.
While several embodiments of the disclosure have been shown in the drawings, it is not intended that the disclosure be limited thereto, as it is intended that the disclosure be as broad in scope as the art will allow and that the specification be read likewise. Therefore, the above description should not be construed as limiting, but merely as exemplifications of particular embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto.
This application claims the benefit of U.S. Provisional Application Ser. No. 63/250,376 filed Sep. 30, 2021, the entire contents of which being incorporated by reference herein.
Number | Date | Country | |
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63250376 | Sep 2021 | US |