The present invention relates to electrosurgical instruments and the control of multimodal electrosurgical energy in such instruments. In particular, but not by way of limitation, the present invention relates to systems and methods for selectively delivering both bipolar and monopolar electrical energy through a single electrosurgical instrument.
In general, monopolar electrosurgery is the passage of high-frequency current to tissue through a single heating (or active) electrode to a return electrode positioned remotely from the active electrode where heating does not take place. Bipolar electrosurgery is the passage of high frequency current to tissue between two commonly-supported electrodes where both actively heat tissue.
Monopolar configurations are widely used for general cutting and coagulation procedures, usually utilizing applications of energy of 1 to 5 seconds. Monopolar electrosurgery is widely recognized to be ideal for spray coagulation where there is heating across a surface of tissue proximal to an active electrode. The current field will include a large portion of the patient, but will have high current density only near the active electrode.
Bipolar configurations are widely used for procedures such as coagulation and ablation of tissue where a volume of tissue is positioned between two active electrodes and heated for several seconds, or tens of seconds. The current field in a bipolar device is contained within the neighborhood of the two electrodes.
Many surgeons regularly alternate between bipolar and monopolar instruments in a single surgical procedure. For example, an operating room may utilize ValleyLab monopolar generators and a Wolf bipolar generator all stacked on a single equipment cart. In addition, current monitoring systems, such as an Active Electrode Monitor “AEM” made by Encision, Inc. of Boulder, Colo., may also be incorporated into the overall hardware configuration. Such equipment setups are especially common during OB/GYN procedures. Because the change over between the two generators and instruments takes some time and operating room resources, it is desirable to have a single generator/AEM monitor/controller system that utilizes a single specialized instrument capable of operating in either monopolar or bipolar electrical modes. Such an equipment configuration would minimize changeover time or effectively eliminate changeover time altogether. A description of Active Electrode Monitoring can be found in U.S. Pat. No. 5,312,401, the details of which are incorporated by reference in its entirety. Encision, Inc. of Boulder, Colo. manufactures several AEM systems and configurations for use during electrosurgical procedures.
Given that it is preferable for a single generator to be used with an AEM monitor and controller, it is also desirable to avoid processing either the monopolar or the bipolar outputs in order to utilize both electrical modes (e.g. by deriving the bipolar output from the monopolar output). This configuration allows transparent functioning of the generator manufacturer's electrosurgical modes but requires that the two outputs be isolated in order to prevent damage or distortion.
While the presently utilized combinations of devices are functional, they do not provide the ability to quickly and easily switch between bipolar and monopolar modes and cannot avoid using multiple tools and generator hardware to accomplish both types of electrosurgery. Accordingly, a system and method are needed to address the shortfalls of present technology and to provide other new and innovative features.
Exemplary embodiments of the present invention are shown in the drawings and are summarized below in the accompanying description. It is to be understood, however, that there is no intention to limit the invention to the forms described herein. One skilled in the art can recognize that there are numerous modifications, equivalents and alternative constructions that fall within the spirit and scope of the invention as expressed in the claims. Numerous other embodiments, implementations, and details of the invention are easily recognized by those of skill in the art from the following descriptions and claims.
An electrical switching system for use in various types of electrosurgical instruments and related tools comprises a system adapted to automatically determine which of at least two electrical current modes to deliver through an electrosurgical instrument based on a condition sensed by the electrosurgical instrument.
In another embodiment, an electrical switching system for selectively delivering either bipolar or monopolar electrical energy through a surgical instrument comprises a generator, the generator including a first electrical distribution system for delivering monopolar electrical energy, and a second electrical distribution system for delivering bipolar electrical energy, a controller coupled to the generator for selecting based on an input which of the first and second electrical distribution systems to activate. The controller comprises a first pair of relays actively coupled to the first electrical distribution system, a second pair of relays actively coupled to the second electrical distribution system, a switch for selecting either the first electrical distribution system or the second electrical distribution system, and a keying circuit coupled to the switch for selectively engaging either the first or second electrical distribution systems.
In another embodiment, an electrical connection system for selectively delivering either bipolar or monopolar electrical energy through a surgical instrument comprises a generator including a first electrical distribution system for delivering monopolar electrical energy, and a second electrical distribution system for delivering bipolar electrical energy. The electrical connection system also comprises a controller coupled to the generator for selecting based on an input which of the first and second electrical distribution systems to activate, the controller comprising a first pair of relays electrically coupled to the first electrical distribution system, a second pair of relays electrically coupled to the second electrical distribution system, a switch for selecting either the first electrical distribution system or the second electrical distribution system, a keying circuit coupled to the switch for selectively engaging either the first or second electrical distribution systems, a third set of relays coupled to the first and second set of relays, and an impedance sensing circuit coupled to and disposed between the logic circuit and the third set of relays.
In a further embodiment, a surgical instrument comprises means for selectively delivering either bipolar or monopolar electrical current while also being adapted to utilize a monitoring system such as active electrode monitoring.
Various other embodiments and variations will become evident in conjunction with the attached description and drawing figures. One of skill in the art will easily recognize that the scope of the present invention is not to be limited by the description herein.
Various objects and advantages and a more complete understanding of the present invention are apparent and more readily appreciated by reference to the following detailed description and to the appended claims when taken in conjunction with the accompanying drawings wherein:
Referring now to the drawings,
In general, the instrument tube assembly 100 comprises a tubular body 101 and a pair of operative jaws 103 and 105 connected at a hinge point 107. Labels E1 and E2 represent first and second electrical conductors coupled with jaws 103 and 105 respectively. S is a shield conductor coupled to a safety shield incorporated into the tube assembly.
In another embodiment constructed in accordance with the present invention, the general instrument structure of
In accordance with one aspect of a device constructed in accordance with the present invention, a electrical connection scheme and system for coupling the monopolar and bipolar outputs of a generator to an instrument generally comprises a process and structure that effectively isolates the monopolar and bipolar outputs while also eliminating the need to drive the unused generator output through a controller. One embodiment of such a connection scheme s shown in
With further reference to
The AEM system 222 is preferably one that is known in the art and may operate with its own current processing. Alternately, through a connection 223, a voltage reference can additionally be read in order to ascertain a phase comparison. These monitoring techniques may be used independently or in conjunction with each other in order to provide feedback to the generator 206 and to shut down the flow of current upon the occurrence of a fault condition. The operation of the AEM system 222 can be accomplished by known means, for example as described in U.S. Pat. No. 5,312,401 or as implemented in the AEM devices sold by Encision, Inc.
The schematic diagram of
As described above, in one embodiment the control of monopolar and bipolar modes is accomplished via a footswitch 210. The footswitch 210 preferably houses an additional treadle 212 compared to the nominal cut/coagulation selection treadles 214 and 216 in order enable a user to switch between the monopolar and bipolar modes. An alternate means of monopolar/bipolar control contemplated by the present invention is to provide a front panel control switch located on the generator being used as the monitor/controller. Such a controller scheme may also be combined with an automated sensing feature that senses the conditions at the tines (jaw) of the instrument in order to produce the desired tissue effects. The table below represents one such algorithm used for automatic selection of monopolar and bipolar operation. Such an algorithm may be implemented in software, hardware, firmware, or another means as is known in the art.
Thus, as seen from the above data, bipolar functionality is selected if tissue is positioned across the instrument jaws.
In order to alert a user as to which type of energy is currently active, it is preferable to have the generator or controller generate a distinctive audible tone or tone sequence that indicates the mode that is active or that indicates that a particular mode is about to be activated. For example, upon activation of monopolar current, a continuous tone would be heard where upon activation of bipolar current, a repeating tone would be heard. Other audible schemes are contemplated and visual indicators may also be included on the generator, controller, or instrument itself to alert the user as to the type of RF energy that is currently active within the device.
In other embodiments, the controller has a load impedance sensor that is active at least in the RF idle state, but could also be active in the RF active state as well. Such an impedance sensor operates on the load impedance between the jaws of the grasper and preferably makes measurements every few tenths of a second. In a preferred implementation, the monopolar/bipolar switch sensing is accomplished in the idle state just prior to RF activation.
In
While various embodiments of the impedance sensing circuit 340 are contemplated, as an example, the circuits disclosed in U.S. Pat. No. 4,416,277 (shown as
In accordance with the above and with various aspects of the present invention, a bipolar/monopolar electrosurgical device may be used in a variety of way an in conjunction with many different surgical procedures. For example in a laparoscopically assisted vaginal hysterectomy (LAVH), bipolar functionality would be used for taking down the broad ligament and sealing the uterine arteries. Monopolar functionality would be used for the general control of bleeding in transected tissue including coagulation of capillary bleeding.
Bipolar devices, as opposed to monopolar devices, typically exhibit more friction in the operation of the inserts and are often perceived as requiring a high force to actuate. The increased force required results from a combination of several factors, including the geometry of the handle, the geometry of the tip linkage and friction with the system. This can be attributed to, among other potential issues, the fact that insulation in bipolar jaw structures tend to contribute to mechanical interference and thus increased friction. Also, the dual active contacts required increase the sliding friction with the insert. To mitigate this increased friction, a device constructed in accordance with the present invention preferably includes one or two active contacts that involve a highly flexible wire 612 and a self-positioning sliding interface 604 as shown in conjunction with
These friction problems may also be solved in one or more of the following ways. First, by relieving interference through appropriate design of the housing tolerances and interaction of the internal components. Second, by controlling the dimensions of the jaw contact blades, sliding friction may be reduced. Third, by specially designing the contacts so that have very low friction themselves. For example, this can be accomplished by eliminating the sliding interface between the contact and the insert assembly and allowing the contact member to float longitudinally with electrical conduction performed by a flexible wire. This method greatly reduces the friction in the system.
A solution in accordance with one aspect of the present invention allows the contact to fit snugly within the housing and around the rod while also allowing the housing to float within an outer housing. The electrical connection is preferably made with a flexible wire which would allow the contact housing to slide back and forth with very little friction. Referring to
The inside of the contact housing 606 is driven by the sizing requirements of the spring contact 604. The outside of the housing 606 is preferably square or rectangular. The contact housing fits inside of an outer housing 608 with a small clearance. The outer housing 608 is preferably sized to allow the inner housing 606 to move at least as much as the actuation distance of the worst case articulated instrument. The housing preferably has a chamfer on its distal end to guide the rod during insertion.
A flexible wire 610 is connected to both the contact housing 606 and an active wire 612. There are a number of solutions to the type of wire and connection means used. A connection of this type allows the contact housing 606 to slide back and forth in the outer housing with very little friction compared to the current situation of the contact on the rod. The square cross section of the contact housing and the outer housing keeps the wire from being rotated and possibly being bent or hindering the movement between the contact housing 606 and the outer housing 608.
In use, the active rod 602 is inserted from the distal end 614. As the rod 602 goes through the contact 604, the contact housing 606 is pushed to the end of the chamber 616 created by the outer housing 610. If the instrument is inserted in the handle with the jaws apart, this travel is completed when the contact is closed the first time.
Aspects of the present invention provide, among other things, a system and method for easily, quickly, and safely allowing a surgeon or other user to switch between bipolar and monopolar energy delivery during an electrosurgical procedure, the ability to minimize the friction commonly associated with the use of bipolar instruments, and the ability to incorporate an active electrode monitoring system in both bipolar and monopolar electrosurgical modes. Those skilled in the art can readily recognize that numerous variations and substitutions may be made in the invention, its use and its configuration to achieve substantially the same results as achieved by the embodiments described herein. Accordingly, there is no intention to limit the invention to the disclosed exemplary forms. Many variations, modifications and alternative constructions fall within the scope and spirit of the disclosed invention as expressed in the claims.
This application claims the benefit of Provisional U.S. Patent Application No. 60/804,601 filed on Jun. 13, 2006. The details of Application No. 60/804,601 are incorporated by reference into the present application in their entirety.
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