Covidien LP

Covidien Ag

Kenneth C Brockmann

Donald W Heckel

William D Faulkner

Katherine Wagle

Ryan C Artale

Jessica E C Olson

Jeffrey R Unger

Rebecca J Coulson

Alexander M Waskiewicz

Joshua A Keller

Gregory P Milner

Jeffrrey R Unger

An electrosurgical system including or connected to an output circuitry comprising an electrosurgical device and an electrical cable is modeled during a cable interrogation phase using a transfer matrix in order to determine a leakage capacitance in the electrosurgical system. After the leakage capacitance is assigned or set to a virtual capacitor in the transfer matrix, an output parameter of the electrosurgical system, such as output voltage, output current, output impedance or output electrical power, may be determined by applying an actual input voltage to the output circuitry and measuring a resulting input current, and multiplying the input voltage and measured current by the transfer matrix.

System and method for controlling operation of an electrosurgical system

An electrosurgical system including or connected to an output circuitry comprising an electrosurgical device and an electrical cable is modelled during a cable interrogation phase using a transfer matrix in order to determine a leakage capacitance in the electrosurgical system. After the leakage capacitance is assigned or set to a virtual capacitor in the transfer matrix, an output parameter of the electrosurgical system, such as output voltage, output current, output impedance or output electrical power, may be determined by applying an actual input voltage to the output circuitry and measuring a resulting input current, and multiplying the input voltage and measured current by the transfer matrix.

An electrosurgical generator is disclosed. The generator includes an RF output stage configured to supply electrosurgical energy to tissue via at least one active electrode configured to apply electrosurgical energy to tissue; sensing circuitry configured to measure impedance of tissue; and a controller. The controller is configured to determine occurrence of a tissue reaction as a function of a minimum impedance value and a predetermined rise in impedance, wherein tissue reaction corresponds to a boiling point of tissue fluid; generate a target impedance trajectory as a function of measured impedance and desired rate of change based on the tissue reaction determination, wherein the target impedance trajectory includes a plurality of target impedance values; and drive tissue impedance along the target impedance trajectory by adjusting the output of the electrosurgical generator to substantially match tissue impedance to a corresponding target impedance for at least a predetermined minimum time period.

System and method for tissue sealing

Growing community of inventors

Boulder, CO, United States of America

Kenneth C Brockmann