Examples presented herein generally include systems and methods which can contact electrodes to cardiac tissue while sensing electrical potential from fluids near the tissue. The electrodes in contact with the tissue can be carried by an end effector and can be used to sense and/or ablate the tissue they contact. A reference electrode can be insulated by a shaft connected to the end effector so that the reference electrode can sense the electrical potentials from the fluids near the tissue while being prevented, by the shaft geometry, from contacting the cardiac tissue. In some examples, the reference electrode can be tubular, having an inner surface that is configured to contact and sense electrical potentials from the fluids and an electrically insulated outer surface. Configured as such, the reference electrode can serve as an extension of an irrigation tube extending through the shaft.

Systems and methods for estimating tissue parameters, including mass of tissue to be treated and a thermal resistance scale factor between the tissue and an electrode of an energy delivery device, are disclosed. The method includes sensing tissue temperatures, estimating a mass of the tissue and a thermal resistance scale factor between the tissue and an electrode, and controlling an electrosurgical generator based on the estimated mass and the estimated thermal resistance scale factor. The method may be performed iteratively and non-iteratively. The iterative method may employ a gradient descent algorithm that iteratively adds a derivative step to the estimates of the mass and thermal resistance scale factor until a condition is met. The non-iterative method includes selecting maximum and minimum temperature differences and estimating the mass and the thermal resistance scale factor based on a predetermined reduction point from the maximum temperature difference to the minimum temperature difference.

Techniques are disclosed to cauterize tissue. For example, certain aspects herein relate to a cautery device. The cautery device includes a voltage source comprising a voltage pump and a battery. The cautery device further includes a probe for applying current from the voltage source to tissue. The probe includes a first electrically conductive element electrically coupled to a first pole of the voltage source. The probe further includes a second electrically conductive element coupled to a second pole of the voltage source.

An electrosurgical wand is provided and includes a handle and an elongate shaft coupled to the handle and extending distally from the handle along an axis. An active electrode is disposed at a distal end of the electrosurgical wand. A return electrode abuts the elongate shaft and extends along and annularly about the axis. The return electrode has a top side adjacent the active electrode and an opposite bottom side and defines a notch. A support member is disposed in the notch between the electrodes and transitions curvilinearly from the notch to define a front surface extending laterally across and axially from the return electrode. The front surface tapers downwardly from the active electrode to define a first portion defining a first convex outer surface and also extends toward the bottom side of the return electrode to define a second portion defining a second convex outer surface.

An interchangeable tool assembly is disclosed. The interchangeable tool assembly includes a first jaw configured to support a staple cartridge during a first time period and a radio-frequency cartridge during a second time period. A second jaw is coupled to the first jaw. A surface of the second jaw defines a plurality of staple forming pockets configured to form staples driven from the staple cartridge. An electrically insulative material covers segments of the surface of the second jaw other than the staple forming pockets. The staple forming pockets define at least one return path for radio-frequency energy delivered by the radio-frequency cartridge.

An ultrapolar telescopic electrosurgery pencil/handpiece with or without smoke evacuation that is capable of cutting with a sharp non-conductive cutting end of an electrosurgery blade and cutting and coagulating with activation of active and return contacts both contained on each side of the electrosurgery blade.

An electrode assembly is provided. The electrode assembly includes a proximal end that is adapted to connect to an electrosurgical instrument including a housing defining a longitudinal axis therethrough and an electrosurgical energy source. A distal end includes a cutting electrode having a loop configuration configured to cut tissue. The distal end includes a return electrode operably disposed adjacent the cutting electrode. A dielectric shield is operably disposed between the cutting electrode and return electrode. The dielectric shield extending distally past the cutting electrode to hinder current flow to the return electrode when the dielectric shield, cutting electrode and return electrode are submersed in a conductive solution and the cutting electrode is energized, thereby concentrating current density at the cutting electrode.

An apparatus (20f) for removing a blockage from a body of a subject includes a reference electrode (26), configured for insertion into the body, an electrically-insulative element (68) covering the reference electrode, the electrically-insulative element being shaped to define a gap (72) that exposes a portion of the reference electrode, an active electrode (28) covering the electrically-insulative element, and an electrically-conductive element (32) passing through the reference electrode and electrically connected to the active electrode, the electrically-conductive element being configured to electrically connect the active electrode to a power source (34) such that application, by the power source, of a voltage between the active electrode and the reference electrode causes the active electrode to attract the blockage. Other embodiments are also described.

An electrode arrangement according to the invention for a bipolar resectoscope (50) comprises an elongate electrode carrier (2), an active electrode disposed at a distal end of the electrode carrier (2) and a neutral electrode, wherein a distal end section of the electrode carrier (2) is embodied as an electrode body (4, 40) through which a supply line (20) of the active electrode is guided and wherein the neutral electrode is formed by the electrode body (4, 40) or a portion of the electrode body (4, 40). The invention also relates to a resectoscope (50).

A tool assembly for use with an electrosurgical device for cutting tissue includes a base portion, an electrical insulator extending distally from the base portion, a return lead adapted to be electrically coupled to a return terminal, and an active lead adapted to be electrically coupled to an active terminal. The return lead is movably supported on the electrical insulator. The active lead is fixed to the electrical insulator. The return lead is rotatable about a pivot and translatable along a longitudinal axis relative to the electrical insulator and the active lead. Upon activation, electrosurgical energy is transmitted from the active lead through tissue to the return lead to cut tissue in contact with the active lead.