Electrosurgical system

Abstract

An electrosurgical generator arranged to supply radio frequency (RF) energy to fuse tissue is provided. The generator is arranged to supply RF energy through a removably coupled electrosurgical instrument to fuse tissue grasped by the instrument. The generator monitors a phase angle of the supplied RF energy and adjusts or terminates the supplied RF energy based on the monitored phase angle in comparison to predetermined thresholds and conditions to optimally fuse the tissue. The electrosurgical instrument conducts radio frequency energy to fuse tissue captured between the jaws and a blade to mechanically cut tissue between the jaws. A conductive post positioned on the jaw adjacent to the blade.

1 . An electrosurgical system comprising:
 an electrosurgical instrument arranged to grasp and fuse tissue using radio frequency (RF) energy, the electrosurgical instrument comprises: 
 a first jaw having a first electrode; 
 a second jaw coupled to the first jaw and having a second electrode facing the first electrode, the first and second electrodes arranged to conduct the RF energy between the first and second electrodes and the first and second electrodes being made of the same conductive material; 
 an elongate shaft having a proximal end and a distal end and a longitudinal axis extending from the proximal end to the distal end, the first and second jaws being pivotably coupled to the distal end of the elongate shaft; and 
   a conductive post incorporated into the second jaw and extending from the second jaw towards the first jaw, the conductive post being stationary, made of the same conductive material as the first and second electrodes and having an upper portion extending past an upper surface of the second electrode and a lower portion encased in an insulated material in the second jaw, the insulated material separating the conductive post from the second electrode and conductive material in the second jaw; and   an electrosurgical generator connectable to the electrosurgical instrument and configured to supply the RF energy through the electrosurgical instrument to the first and second electrodes and not the conductive post, the electrosurgical generator comprising: 
 an RF amplifier to supply RF energy through the electrosurgical instrument; and 
 an RF sense circuitry arranged to receive a supplied RF waveform from the supplied RF energy through the electrosurgical instrument, the RF sense circuitry comprising a synchronous detector arranged to calculate real and imaginary voltage and current components of the supplied RF waveform. 
   
     
     
         2 . The system of  claim 1  wherein the RF sense circuitry is arranged to determine a phase angle of the supplied RF energy from the calculated real and imaginary voltage and current components and further comprising a controller arranged to signal the RF amplifier to terminate the supply of RF energy when the determined phase angle is less than a predefined phase value. 
     
     
         3 . The system of  claim 2  wherein the predefined phase value is a negative value. 
     
     
         4 . The system of  claim 3  wherein the controller is configured to compare an identified voltage to a predetermined voltage value to determine the predefined phase value. 
     
     
         5 . The system of  claim 4  wherein the RF Sense circuitry measures voltage and current of the supplied RF energy from the RF amplifier and generates DC signals representing voltage, current, power, and phase of the measured voltage and current and wherein the controller further comprises a RF smoother arranged to remove noise from the generated DC signals from the RF sense and extrapolate from the generated DC signals smooth modulated DC signals representative of the voltage, current, power, and phase of the supplied RF energy. 
     
     
         6 . The system of  claim 5  wherein the synchronous detector is arranged to calculate real and imaginary voltage and current components of the supplied RF waveform using synchronization signals. 
     
     
         7 . The system of  claim 6  wherein the RF sense circuitry calculates a root means square (RMS) voltage, RMS current, apparent power and phase using the calculated real and imaginary voltage and current components. 
     
     
         8 . The system of  claim 7  wherein the electrosurgical instrument further comprises a blade movable along the longitudinal axis from a proximal position to a distal position and back to the proximal position, the blade disposed within an outer periphery of the second jaw and the second jaw includes a channel through which the blade traverses there through. 
     
     
         9 . The system of  claim 8  wherein the blade is made of a conductive material that is the same as the conductive material of the conductive post and an entire surface of the first jaw facing the second jaw is smooth and flat having no indentations or pockets. 
     
     
         10 . The system of  claim 9  wherein the electrosurgical instrument further comprises an actuator disposed on the proximal end of the elongate shaft and arranged to be user accessible where manipulation of the actuator moves the first and second jaws, initiates the supply of RF energy or translational movement of the blade. 
     
     
         11 . The system of  claim 10  wherein the electrosurgical generator is arranged to supply RF energy only to the first and second electrodes and not the conductive post and the blade. 
     
     
         12 . The system of  claim 11  wherein the electrosurgical instrument further comprises a switch that causes the generator to supply RF energy. 
     
     
         13 . The system of  claim 12  wherein the controller of the generator logs the usage of both the instrument and the generator. 
     
     
         14 . The system of  claim 13  wherein the conductive post is affixed to the second jaw by an over-molding. 
     
     
         15 . The system of  claim 13  wherein the conductive post is arranged to contact the first electrode. 
     
     
         16 . The system of  claim 15  wherein the conductive post has a flat upper atraumatic surface. 
     
     
         17 . The system of  claim 16  wherein the conductive post is disposed adjacent to the channel of the second jaw. 
     
     
         18 . The system of  claim 16  further comprising a temperature sensor disposed within the second jaw and proximate the conductive post. 
     
     
         19 . The system of  claim 16  wherein the conductive post includes a plurality of conductive posts having varying heights and the plurality of conductive posts includes a distal most conductive post having a height greater than a height of a proximal most conductive post. 
     
     
         20 . The system of  claim 19  wherein the plurality of conductive posts are disposed adjacent to the channel of the second jaw.