A catheter device for renal denervation ablation includes a flexible catheter shaft having an electrically insulating expandable member in its distal portion with at least one electrode located proximal to the member, at least one electrode located distal to the member, and with openings in the distal shaft with at least one opening proximal to the proximal electrode and one opening distal to the distal electrode of said electrode pair, said openings connected through an inner lumen in the catheter that provides a path for blood to flow through the expandable member. In one embodiment, the device comprises a flexible catheter shaft with a multiplicity of recessed paired electrodes disposed in recessed spaces in its distal portion, such that an electrically conducting portion of each electrode is exposed to the exterior of the catheter within a recessed space, and with an electrical insulator separating the electrodes of each pair.

Systems and methods for monitoring return patch impedances are provided. A tissue therapy system includes a catheter comprising at least one electrode, the catheter implantable in a patient, a first return patch electrode configured to be applied to skin of the patient, a second return patch electrode configured to be applied to the skin of the patient, and an impedance measuring circuit lectrically coupled to the at least one catheter electrode, the first return patch electrode, and the second return patch electrode. The impedance measuring circuit is configured to drive currents between the at least one catheter electrode, the first return patch electrode, and the second return patch electrode, detect, using a voltage at the at least one catheter electrode as a reference voltage, voltages generated in response to the driven currents, and measure impedances based on the driven currents and the detected voltages.

An ultrasonic device may include an electromechanical ultrasonic system that includes an ultrasonic transducer coupled to an ultrasonic blade. A method of delivering energy to the ultrasonic device may include sensing a vessel type in contact with the blade, determining that the vessel type is either a vein or an artery, and delivering power to the transducer based on the vessel type. Power may be applied to the transducer at a power level P that differs from a nominal power level Pn for a period T that differs from a nominal period Tn based on the vessel. The power level P may be lower than Pn for a period T that is longer than Tn when the vessel is a vein. Alternatively, the power level P my be greater than Pn for a period T that is shorter than Tn when the vessel is an artery.

An ultrasonic device may include an electromechanical ultrasonic system defined by a predetermined resonant frequency and include an ultrasonic transducer coupled to an ultrasonic blade. A method of delivering energy to the device may include applying energy to the blade at a first power level via the transducer coupled to the blade, measuring a complex impedance of the transducer, receiving a complex impedance feedback data point, comparing the complex impedance feedback data point to a reference complex impedance characteristic pattern, and determining that the blade is contacting a vessel based on the comparison. The method may also include disabling the power applied to the transducer and switching to a lower power level. The method may further include generating a warning that the blade is contacting a vessel, such as a light or a sound. An ultrasonic surgical instrument may effect the method.

Aspects of the present disclosure are presented for managing simultaneous outputs of surgical instruments. In some aspects, methods are presented for synchronizing the current frequencies. In some aspects, methods are presented for conducting duty cycling of energy outputs of two or more instruments. In some aspects, systems are presented for managing simultaneous monopolar outputs of two or more instruments, including providing a return pad that properly handles both monopolar outputs in some cases.

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.

A surgical system includes a power supply, a power stage coupled to the power supply for converting electric energy to a power signal, an audio output device, a sensor, and a controller coupled to the power supply, the power stage, and the audio output device. The controller is operably coupled to the sensor. The power stage is configured to transmit the power signal to a surgical instrument such as an electrosurgical instrument or a microwave instrument. The sensor may be disposed on the surgical instrument. The controller causes the audio output device to output sensory feedback during operation of the surgical generator based on sensor signals received from the sensor during a surgical procedure.

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

An electrosurgical generator is disclosed. The electrosurgical generator includes: a power supply configured to output DC power; an inverter coupled to the power supply, the inverter including a plurality of switching elements; and a controller coupled to the inverter and configured to signal the inverter to simultaneously generate based on the DC power a radio frequency heating waveform and an electroporation waveform.

A gas-enhanced electrosurgical generator. The gas-enhanced generator has a housing, a first gas control module in the housing and configured to control flow of a first gas, a second gas control module in the housing and configured to control flow of a second gas, a high frequency power module, and a controller, processor or CPU within the housing and configured to control the first gas control module, the second gas control module and the high frequency power module. The first gas and second gas may be any of CO.sub.2, argon and helium or another gas. The gas-enhanced electrosurgical generator may have a third gas control module in the housing and configured to control flow of a third gas and a third connector secured on an exterior of the housing.