Electrosurgical methods and systems

Abstract

Electrosurgical methods and systems. At least some of the illustrative embodiments are methods including maintaining plasma proximate to an active electrode in a first energy range, and a second energy range. During periods when plasma is proximate to the active electrode, the illustrative method may include controlling flow of fluid drawn into an aperture of an electrosurgical wand, and in some situations increasing fluid flow drawing into the aperture responsive to the active electrode being in operational relationship with tissue, and in other cases decreasing fluid flow drawing into the aperture responsive to the active electrode being in operational relationship with tissue. Further, during periods when plasma is proximate to the active electrode, the illustrative method may include providing output energy at a default energy setpoint, and then providing output energy at a second energy setpoint.

What is claimed is: 
     
         1 . An electrosurgical wand comprising:
 an active electrode at a distal end of the electrosurgical wand, a handle at a proximal end of the electrosurgical wand and a shaft therebetween;   an aspiration conduit extending along the shaft, configured to receive a fluid therethrough, the aspiration conduit having a distal opening adjacent the active electrode;   a temperature sensor communicably coupled to an external surface of the aspiration conduit at the electrosurgical wand proximal end, the temperature sensor configured to detect a localized temperature increase associated with the fluid traveling along an underlying lumen of the aspiration conduit.   
     
     
         2 . The electrosurgical wand of  claim 1  wherein the temperature sensor is disposed within an inner cavity of the handle. 
     
     
         3 . The electrosurgical wand of  claim 1  wherein the aspiration conduit includes a flexible tubular member, and wherein the temperature sensor abuts an external surface of the flexible tubular member. 
     
     
         4 . The electrosurgical wand of  claim 3  wherein the flexible tubular member extends through an inner cavity of the handle. 
     
     
         5 . The electrosurgical wand of  claim 3  wherein the flexible tubular member extends through and proximally from the handle and is configured to operatively couple to a peristaltic pump, the peristaltic pump configured to control an aspiration flow rate through the aspiration conduit. 
     
     
         6 . The electrosurgical wand of  claim 1  wherein the aspiration conduit includes a lumen of the shaft and a flexible tubular member fluidly coupled to a proximal end of the shaft lumen, the temperature sensor abutting the flexible tubular member. 
     
     
         7 . The electrosurgical wand of  claim 1  wherein the temperature sensor comprises at least one of a resistive thermal device, a thermistor, an optical temperature probe or thermocouple. 
     
     
         8 . The electrosurgical wand of  claim 1  wherein the electrosurgical wand is configured to be inserted through a port and treat tissue within a patient joint, and wherein the temperature sensor if located along the electrosurgical wand external to the patient joint. 
     
     
         9 . An electrosurgical system comprising:
 an electrosurgical wand comprising:
 an active electrode at a distal end of the electrosurgical wand, a handle at a proximal end of the electrosurgical wand and a shaft therebetween; 
 an aspiration conduit extending along the shaft, configured to receive a fluid therethrough, the aspiration conduit having a distal opening adjacent the active electrode; and 
 a temperature sensor abutting an external surface of the aspiration conduit at the electrosurgical wand proximal end, the temperature sensor configured to determine a temperature associated with the fluid traveling along an underlying lumen of the aspiration conduit; and 
   a high frequency power supply, the high frequency power supply configured to couple to the active electrode;   
       wherein the electrosurgical wand and the high frequency power supply are configured to form an ionized vapor layer in an electrically conductive fluid in a region between the active electrode and a target tissue so as to volumetrically remove the target tissue. 
     
     
         10 . The electrosurgical system of  claim 9  wherein the electrosurgical wand proximal end includes a handle with an inner cavity, and wherein the temperature sensor is disposed within the inner cavity. 
     
     
         11 . The electrosurgical system of  claim 9  wherein the aspiration conduit includes a flexible tubular member, and wherein the temperature sensor abuts an external surface of the flexible tubular member. 
     
     
         12 . The electrosurgical system of  claim 11  wherein the electrosurgical wand proximal end includes a handle with an inner cavity and wherein the flexible tubular member extends through an inner cavity of the handle. 
     
     
         13 . The electrosurgical system of  claim 11  wherein the flexible tubular member extends from the electrosurgical wand and is configured to operatively couple to a means of controlling aspiration. 
     
     
         14 . The electrosurgical system of  claim 13  wherein the means of controlling aspiration is a peristaltic pump configured to control an aspiration flow rate through the aspiration conduit. 
     
     
         15 . The electrosurgical wand of  claim 9  wherein the aspiration conduit includes a lumen of the shaft and also a flexible tubular member extending proximally therefrom, the temperature sensor abutting the flexible tubular member. 
     
     
         16 . The electrosurgical wand of  claim 9  wherein the temperature sensor comprises at least one of a resistive thermal device, a thermistor, an optical temperature probe or thermocouple. 
     
     
         17 . An electrosurgical wand comprising:
 an active and return electrode at a distal end of the electrosurgical wand, a handle at a proximal end of the electrosurgical wand and a shaft therebetween;   an aspiration conduit extending along the shaft, configured to receive a fluid therethrough, the aspiration conduit having a distal opening adjacent the active electrode;   a temperature sensor communicable coupled to an outer surface of the electrosurgical wand at a location adjacent the handle, the temperature sensor configured to detect a localized temperature increase associated with the fluid traveling along an underlying lumen of the aspiration conduit.   
     
     
         18 . The electrosurgical wand of  claim 17  wherein the temperature sensor is disposed within an inner cavity of the handle. 
     
     
         19 . The electrosurgical wand of  claim 17  wherein the temperature sensor abuts an outer surface of a tubular member of the electrosurgical wand. 
     
     
         20 . The electrosurgical wand of  claim 16  wherein the temperature sensor abuts an outer surface of a flexible tubular member adjacent the handle.