Ablation systems of the present disclosure facilitate the safe formation of wide and deep lesions. For example, ablation systems of the present disclosure can allow for the flow of irrigation fluid and blood through an expandable ablation electrode, resulting in efficient and effective cooling of the ablation electrode as the ablation electrode delivers energy at a treatment site of the patient. Additionally, or alternatively, ablation systems of the present disclosure can include a deformable ablation electrode and a plurality of sensors that, in cooperation, sense the deformation of the ablation electrode, to provide a robust indication of the extent and direction of contact between the ablation electrode and tissue at a treatment site.

An electrosurgical instrument has a power supply operatively coupled to an end effector. The end effector has a pair of jaws for effectuating an action on tissue positioned therebetween. The power supply is configured to input a first signal and a second signal to a buck-boost converter. The buck-boost converter is configured to transmit an output to an H-bridge circuit. The H-bridge circuit is configured to pass a signal to a resonant LC transformer circuit. The power supply is configured to transmit a power signal. The pair of jaws are operatively coupled to the power supply to receive the power signal, the power having no more than 80 Volts RMS, and less than 2 Amps RMS. The power is configured to seal the tissue positioned between the pair of jaws in 3 seconds or less.

An electrosurgical generator which outputs high-frequency AC voltage for an electrosurgical instrument includes a leakage current detecting device for the connected electrosurgical instrument. The leakage current detecting device is embodied as a voltage measuring device, the inputs of which are connected in each case via a capacitive coupling to an active and a neutral line of the output line and which has a bipolar voltage divider having a predetermined fixed ratio. An asymmetry detector connected via a capacitive coupling compares upper and lower voltage at the voltage divider, and outputs a fault signal for leakage current in the case of deviation of the ratio of upper to lower voltage from the predetermined fixed ratio.

An intravascular catheter for nerve activity ablation and/or sensing includes one or more needles advanced through supported guide tubes (needle guiding elements) which expand to contact the interior surface of the wall of the renal artery or other vessel of a human body allowing the needles to be advanced though the vessel wall into the extra-luminal tissue including the media, adventitia and periadvential space. The catheter also includes structures which provide radial and lateral support to the guide tubes so that the guide tubes open uniformly and maintain their position against the interior surface of the vessel wall as the sharpened needles are advanced to penetrate into the vessel wall. Electrodes near the distal ends of the needles allow sensing of nerve activity before and after attempted renal denervation. In a combination embodiment ablative energy or fluid is delivered from the needles in or near the adventitia to ablate nerves outside of the media while sparing nerves within the media.

A method for constructing a modular surgical system is disclosed. The method comprises providing a header module comprising a first power backplane segment, providing a surgical module comprising a second power backplane segment, assembling the header module and the surgical module to electrically couple the first power backplane segment and the second power backplane segment to each other to form a power backplane, and applying power to the surgical module through the power backplane.

Apparatus and associated methods relate to controlling electrical power of an electrotherapeutic signal that is provided to a biological tissue engaged by an electrosurgical instrument during a medical procedure. Electrical power—a product of a voltage difference across and an electrical current conducted by the engaged biological tissue—is controlled according to a therapeutic schedule. The electrotherapeutic schedule can be reduced or terminated in response to a termination criterion being met. In some examples, the termination criterion is a current characteristic, such as, for example, a decrease in current conducted by the engaged biological tissue. In some examples, the termination criterion is a biological tissue resistance characteristic, such as, for example, an increase in the biological tissue resistance that exceeds a predetermined delta resistance value.

An electrosurgical generator includes: a power supply configured to output a direct current; an energy metering stage including at least one metering switching component operated by a metering switching waveform, the energy metering stage configured to generate a metered energy packet from the direct current; a power converter coupled to the energy metering stage, the power converter including at least one power switching element operated by a power switching waveform, the power converter configured to generate a radio frequency half cycle based on the metered energy packet; and a controller coupled to the power converter, the controller is configured to modulate the metering switching waveform and the power switching waveform.

A system for tissue puncture includes a radiofrequency (RF) generator, an RF puncture device, and at least a first intracorporeal grounding (IG) electrode. RF generator includes an RF output port and a ground return port. The RF puncture device includes an elongate member having a shaft and a tip. The tip includes an intracorporeal RF puncture electrode that is positionable adjacent a target site within a patient’s body, and the shaft includes a first electrical conductor that is electrically connected to the intracorporeal RF puncture electrode and is electrically connectable to the RF output port for delivering RF energy from the RF generator to the intracorporeal RF electrode. The IG electrode is positionable within the patient’s body proximate the target site, and is electrically connectable to the ground return port for returning current to the RF generator.

An ultrasonic surgical instrument and method of sealing a tissue includes generating a desired burst pressure in the tissue, sealing the tissue, verifying that the tissue is sealed with further application of at least one of the ultrasonic energy and the RF energy. The ultrasonic surgical instrument further includes an end effector having an ultrasonic blade, an RF electrode, and a controller. The controller operatively connects to the ultrasonic blade and the RF electrode and is configured to direct application of ultrasonic and RF energies according to an initial phase, a power phase, and a termination phase for respectively generating a desired burst pressure in the tissue, sealing the tissue, and verifying the sealing of the tissue while inhibiting transection of the tissue.

A generator, ultrasonic device, and method for controlling a temperature of an ultrasonic blade are disclosed. A control circuit coupled to a memory determines an actual resonant frequency of an ultrasonic electromechanical system comprising an ultrasonic transducer coupled to an ultrasonic blade by an ultrasonic waveguide. The actual resonant frequency is correlated to an actual temperature of the ultrasonic blade. The control circuit retrieves from the memory a reference resonant frequency of the ultrasonic electromechanical system. The reference resonant frequency is correlated to a reference temperature of the ultrasonic blade. The control circuit then infers the temperature of the ultrasonic blade based on the difference between the actual resonant frequency and the reference resonant frequency. The control circuit controls the temperature of the ultrasonic blade based on the inferred temperature