Electrosurgery with infiltration anesthesia

Abstract

Method for carrying out the recovery of an intact volume of tissue wherein a delivery cannula tip is positioned in confronting adjacency with the volume of tissue to be recovered. The electrosurgical generator employed to form an arc at a capture component extending from the tip is configured having a resistance-power profile which permits recovery of the specimen without excessive thermal artifact while providing sufficient power to sustain a cutting arc. For the recovery procedure, a local anesthetic employing a diluent which exhibits a higher resistivity is utilized and the method for deploying the capture component involves an intermittent formation of a cutting arc with capture component actuation interspersed with pauses of duration effective to evacuate any accumulation or pockets of local anesthetic solution encountered by the cutting electrodes.

1 . The method for carrying out a surgical procedure wherein an electrode is electrosurgically excited to create an arc for cutting tissue of an animal, comprising the steps of: 
 determining an anticipated range of resistance values exhibited by said tissue when confronted by said electrode from a low value to a high value;    providing a said electrosurgical cutting electrode;    providing an electrosurgical generator connectable in electrical excitation relationship with said cutting electrode and having a resistance load verses power characteristic effective to sustain creation of said arc at said electrode when confronting said tissue throughout said range of resistance values;    anesthetizing said animal by parenterally administering a solution of a local anesthetic agent and biocompatible diluent at the site of said tissue, said solution exhibiting a resistivity of value effective to maintain at least said low value of resistance when infiltrated within said tissue; and 
 then carrying out said procedure while electrosurgically exciting said electrode from said electrosurgical generator.  
   
   
   
       2 . The method of  claim 1  further comprising the steps: 
 determining an anticipated range of resistivity values for said tissue from a low value to a high value; and    said step of anesthetizing said animal is carried out with a said solution exhibiting a resistivity of value at least corresponding with said tissue low value of resistivity.    
   
   
       3 . The method of  claim 2  in which said step of providing a local anesthetic provides a said solution exhibiting an electrical resistivity of about 100 ohm-cm or greater.  
   
   
       4 . The method of  claim 2  in which said step of providing a local anesthetic provides a said solution exhibiting an electrical resistivity of about 200 ohm-cm or greater.  
   
   
       5 . The method of  claim 1  further comprising the step: 
 determining an anticipated range of conductivity values for said tissue from a high value to a low value; and    said step of anesthetizing said animal is carried out with a said solution exhibiting a conductivity of value lower than or substantially equal to said low value of conductivity.    
   
   
       6 . The method of  claim 5  in which said step of anesthetizing said animal is carried out with a said solution exhibiting an electrical conductivity of less than about 5 milliSiemens/cm.  
   
   
       7 . The method of  claim 5  in which said step of anesthetizing said animal is carried out with a said solution exhibiting an electrical conductivity of less than about 10 milliSiemens/cm.  
   
   
       8 . The method of  claim 1  in which said step of anesthetizing said animal is carried out with a said solution exhibiting an osmolarity between about 240 and about 340 milliOsmols/liter.  
   
   
       9 . The method of  claim 1  further comprising the steps of: 
 providing an evacuation system having an intake port located in adjacency with said electrode; and    said step carrying out said procedure is carried out by moving said electrode about said tissue in an intermittent manner wherein said electrode is electrosurgically energized to form said arc while being advanced into said tissue for a cutting interval, then is de-energized and maintained stationary for a pause interval while a vacuum is applied at said intake port effective to evacuate accumulations of said solution encountered by said electrode.    
   
   
       10 . The method of  claim 9  in which: 
 said step for providing an evacuation system provides said system as comprising a vacuum pump having a vacuum port and a transparent tube coupled in vacuum communication between said vacuum port and said intake port; and    said pause interval is maintained while said solution is visibly perceptible in said transparent tube.    
   
   
       11 - 22 . (canceled)  
   
   
       23 . The method for carrying out a surgical procedure wherein an electrode is electrosurgically excited to create an arc for cutting at a tissue site of an animal, comprising the steps of: 
 determining the lowest value of resistivity of tissue for such an animal;    providing an electrosurgical system including an electrosurgical generator and an operatively associated cutting electrode assembly energizable to provide a tissue cutting arc;    providing a local anesthetic as a solution of a local anesthetic agent and a biocompatible diluent exhibiting a resistivity substantially corresponding with or greater than said determined lowest value of resistivity;    anesthetizing said animal by parenternally administering said local anesthetic to effect its infiltration about said tissue site; and    then carrying out said procedure while electrosurgically energizing said electrode assembly.    
   
   
       24 . The method of  claim 23  in which said step of providing a local anesthetic provides a said solution exhibiting an osmolarity between about 240 and about 340 milliOsmols/liter.  
   
   
       25 . The method of  claim 23  in which said step of providing a local anesthetic provides a said solution exhibiting an electrical resistivity of about 200 ohm-cm or greater.  
   
   
       26 . The method of  claim 23  in which said step of providing a local anesthetic provides said solution diluent as comprising D-glucos monohydrate in water.  
   
   
       27 . The method of  claim 23  in which said step of providing a local anesthetic provides a said solution exhibiting an electrical resistivity of about 100 ohm-cm or greater.  
   
   
       28 . The method for isolating and retrieving a tissue volume of given peripheral extent within adjacent tissue of a patient, comprising the steps of: 
 (a) providing an electrosurgical generator controllable to derive an electrosurgical cutting output at a cutting voltage level;    (b) providing a tissue retrieval instrument having a delivery cannula and extending from a proximal end portion along a longitudinal axis to a forward region having a tip, said instrument having a capture component positioned within said delivery cannula internal channel having a forward portion extending to a forwardly disposed cutting electrode assembly energizable to define an electrosurgical cutting arc supporting leading edge, said capture component being actuable to cause said leading edge to extend from said delivery cannula laterally outwardly and forwardly toward a maximum peripheral extent selected to correspond with said given peripheral extent and subsequently extendable while being drawn toward said axis to a capture orientation, and said instrument further comprising a controllable motor drive assembly;    (c) providing a control assembly electrically coupled with said electrosurgical generator and said instrument and actuable between a capture mode effecting the energization of said cutting electrode and actuation of said capture component, and a pause mode effecting the de-actuation of said capture component and de-energization of said cutting electrode.    (d) providing a local anesthetic as a solution of a local anesthetic agent and a biocompatible diluent exhibiting a resistivity of value effective for supporting the presence of said cutting arc when infiltrated within said adjacent tissue;    (e) anesthetizing said patient by parenterally administering said local anesthetic to effect said infiltration of said solution;    (f) positioning said delivery cannula within said adjacent tissue in a manner wherein said tip is in confronting adjacency with said tissue volume;    (g) actuating said control assembly to derive said capture mode to effect an isolation and envelopment of said tissue volume; and    (h) removing said delivery cannula with the capture component retained isolated tissue volume from said adjacent tissue.    
   
   
       29 . The method of  claim 28  in which said step of providing a local anesthetic provides a said solution exhibiting an osmolarity between about 240 and about 340 milliOsmols/liter.  
   
   
       30 . The method of  claim 28  in which said step of providing a local anesthetic provides a said solution exhibiting an electrical resistivity of about 200 ohm-cm or greater.  
   
   
       31 . The method of  claim 28  in which said step of providing a local anesthetic provides said solution diluent as comprising an aqueous solution of D-glucos monohydrate.  
   
   
       32 . The method of  claim 28  in which said step of providing a local anesthetic provides a said solution exhibiting an electrical resistivity of about 100 ohm-cm or greater.  
   
   
       33 . The method of  claim 28  further comprising the steps of: 
 (i) providing an evacuation system having an intake port located at said delivery cannula forward region; and    (j) applying a vacuum at said intake port when said control assembly is actuated into said capture mode and said pause mode to promote evacuation of accumulations of said solution.    
   
   
       34 . The method of  claim 33  in which: 
 said step (g) actuating said control assembly is carried out in an intermittent manner by actuating said control assembly to effect said capture mode for a cutting interval, then actuating said control assembly to effect said pause mode for a pause interval.    
   
   
       35 . The method of  claim 34  in which said step (g) carries out said actuation of said control assembly into said capture mode for a said capture interval of from about one second to about 2 seconds.  
   
   
       36 . The method of  claim 34  in which said step (g) carries out said actuation of said control assembly into said pause mode for a said pause interval of from about four seconds to about six seconds.  
   
   
       37 . The method of  claim 34  in which said step (g) includes the steps of: 
 (g1) controlling said electrosurgical generator with said control assembly to provide said electrosurgical cutting output at a boost cutting voltage level for substantially that minimum boost interval effective to create said arc; and    (g2) then controlling said electrosurgical generator with said control assembly to provide said electrosurgical cutting output at an arc supporting cutting voltage level less than said boost cutting voltage level.    
   
   
       38 . The method of  claim 37  in which: 
 said step (g1) provides said electrosurgical cutting output at a said boost cutting voltage level which is greater than said normal cutting voltage level by a factor within a range of about 1.2 to 1.5.    
   
   
       39 . The method of  claim 37  in which: 
 said step (g1) provides said electrosurgical cutting output at said boost cutting voltage level for a boost interval of about 55 milliseconds.    
   
   
       40 - 44 . (canceled)  
   
   
       45 . The method for carrying out a surgical procedure upon a patient comprising the steps of: 
 (a) providing an accessing instrument having an electrosurgical cutting assembly which is energizable to form an electrosurgical cutting arc;    (b) anesthetizing said patient by parenterally administering a solution of a local anesthetic agent and biocompatible into tissue of said patient;    (c) energizing said electrosurgical cutting assembly to effect creation of said cutting arc;    (d) maneuvering said accessing instrument borne electrosurgical cutting assembly to carry out a surgical procedure within the tissue of said patient; and    (e) simultaneously with said step (d) aspirating any accumulation of said solution within the path of said maneuvering to an extent effective to maintain the presence of said cutting arc to cut tissue.