particular embodiments of the present disclosure will be described herein with reference to the accompanying drawings . as shown in the drawings and as described throughout the following description , and as is traditional when referring to relative positioning on an object , the term “ proximal ” refers to the end of the apparatus that is closer to the user and the term “ distal ” refers to the end of the apparatus that is further from the user . in the following description , well - known functions or constructions are not described in detail to avoid obscuring the present disclosure in unnecessary detail . with reference to fig1 , an electrosurgical suction coagulator system 100 is presented having a suction coagulator 110 that is operably coupled to an electrosurgical generator 140 via a conductor 145 . suction coagulator 110 is operably coupled to a vacuum source 150 by a lumen 155 . suction coagulator 110 includes a handle 115 disposed at the proximal end thereof and a elongated shaft 120 extending distally from the handle 115 . the shaft 120 may be formed from material having malleable or flexible properties , for example without limitation , metallic material such as aluminum and alloys thereof and / or polymeric materials such as polyurethane ( pu ) or polyvinyl chloride ( pvc ). a shaft 120 thus formed may be bent to a desired shape by the user , as shown by way of example by bent shaft 120 ′. distal end 124 of shaft 120 includes an exposed tubular electrode 125 for delivering electrosurgical energy to tissue , the electrode 125 having a conduit 126 defined longitudinally therethrough for providing suction to a surgical site . conduit 126 is in fluid communication with vacuum source 150 via lumen 155 . in an embodiment , handle 115 may include a control 130 which may be a handswitch for controlling the application of electrosurgical energy , i . e ., activation and deactivation of an electrosurgical signal . handle 115 may include an additional or second control 131 for controlling the application of suction to the surgical site . in embodiments , control 131 may be operably coupled to a valve ( not shown ) that may be disposed within handle 115 , shaft 120 , vacuum source 150 , and / or lumen 155 . in other envisioned embodiments , control 131 may be operably coupled to a regulator , motor control , or other suitable manner of vacuum control . turning now to fig2 a and 2b , a suction coagulator 200 in accordance with the present disclosure includes a housing 215 disposed proximally to an elongated shaft 220 . housing 215 may be a handle . shaft 220 includes an insulating sheath 226 formed from any suitable dielectric material , for example , polymeric materials such as pu , pvc and the like . shaft 220 includes a conductive tube 224 disposed coaxially within insulating sheath 226 and having a tubular distal tip electrode 225 protruding distally from insulating sheath 226 to form at least one aspiration port 265 . conductive tube 224 may be formed from any suitable electrically conductive material , including without limitation , aluminum or stainless steel . an insulator 270 having a generally cylindrical shape is disposed between conductive tube 224 and insulating sheath 226 . insulator 270 may be formed from any suitable heat - insulating material , for example without limitation , high - temperature polymers , ceramic fiber , or mineral fiber . insulator 270 may be constructed from braided , woven , spun - woven , or randomly dispersed materials . an isolator 260 is disposed between distal tip electrode 225 and conductive tube 224 to thermally insulate the distal tip electrode 225 from the conductive tube 224 and to position distal tip electrode 225 coaxially with the distal end of insulating sheath 226 . distal tip electrode 225 and conductive tube 224 are operably connected by a conductive element 227 , which may be a wire or a strap , to facilitate the delivery of electrosurgical energy to a surgical site ( not shown ) by distal tip electrode 225 . in an embodiment , isolator 260 may be formed of heat - resistant material , for example , ceramic material . in other envisioned embodiments , isolator 260 is integrally formed with sheath 226 . in use , insulator 270 acts to insulate the outer surface of sheath 226 from thermal energy that may propagate from , for example , the surgical site ( not explicitly shown ), distal tip electrode 225 , and / or conductive tube 224 . vacuum source 250 may be selectively activated to provide aspiration suction to tube 224 and tip 225 to facilitate the removal of biodebris from the surgical site ( not explicitly shown ). in another envisioned embodiment best illustrated in fig3 a and 3b , a suction coagulator 300 includes an elongated shaft 320 supported by a housing 315 , the shaft 320 further including an insulator 370 having a generally cylindrical shape that is longitudinally disposed between a conductive tube 324 and a dielectric sheath 326 . insulator 370 may be formed from a closed cell foam material , for example without limitation , closed cell polyurethane foam . a tubular distal tip electrode 325 extends from the distal end of shaft 320 to form at least one aspiration port 365 . an isolator 360 is disposed between distal tip electrode 325 and conductive tube 324 to thermally insulate the distal tip electrode 325 from the conductive tube 324 and additionally to position distal tip electrode 325 coaxially with the distal end of dielectric sheath 326 . distal tip electrode 325 and conductive tube 324 are operably coupled by a conductive element 327 , which may be a wire or a strap . in an embodiment , isolator 360 may be formed of heat - resistant material , for example , ceramic . in other envisioned embodiments , seal 360 may be integrally formed with sheath 326 . in yet another envisioned embodiment best illustrated in fig4 a and 4b , a suction coagulator 400 includes an elongated shaft 420 that is supported by a housing 415 . the shaft 420 includes an insulator 470 having a generally cylindrical shape that is longitudinally disposed between a conductive tube 424 and a dielectric sheath 426 , and an insulator 480 having a generally cylindrical shape that is longitudinally disposed around dielectric sheath 426 . a tubular distal tip electrode 425 extends from the distal end of shaft 420 to form at least one aspiration port 465 . insulators 470 , 480 may be formed from a closed cell foam material , for example without limitation , closed cell polyurethane foam . in use , insulators 470 , 480 act to insulate the outer surface of shaft 420 from thermal energy that may propagate from , for example , the surgical site , distal tip electrode 425 , and / or conductive tube 424 . an isolator 460 is disposed between distal tip electrode 425 and conductive tube 424 to thermally insulate the distal tip electrode 425 from the conductive tube 424 and additionally to position distal tip electrode 425 coaxially with the distal end of dielectric sheath 426 . distal tip electrode 425 and electrode 424 are operably coupled by a conductive element 427 , which may be a wire or a strap . insulator 480 may include at the distal end thereof an annular insulating region 481 that encloses the distal end 425 of dielectric sheath 426 and / or isolator 460 . in embodiments , annular insulating region 481 may be joined to electrode 425 by a bonded region 482 , for example , by adhesive , heat weld , or crimp . turning to fig5 a and 5b , yet another embodiment according to the present disclosure is illustrated wherein a suction coagulator 500 includes an elongated shaft 520 that is supported by a housing 515 . the shaft 520 further including a tubular electrode 524 having generally cylindrical sheath 526 longitudinally disposed around the outer surface thereof . an insulator 580 is concentrically disposed around sheath 526 . insulator 580 may be formed from a closed cell foam material , for example without limitation , closed cell polyurethane foam . in use , insulator 580 acts to reduce the propagation of thermal energy from , for example , the surgical site , an electrode tip 525 , and / or electrode 524 , to the outer surface of shaft 520 . in fig6 a and 6b there is illustrated an envisioned embodiment of a suction coagulator 600 in accordance with the present disclosure wherein an elongated longitudinal shaft 620 is supported by a housing 615 . an open cell foam cover 680 surrounds shaft 620 . the shaft 620 includes a tubular electrosurgical electrode 624 disposed longitudinally therethrough , the tubular electrosurgical electrode 624 having an exposed tip 625 for delivering electrosurgical energy to tissue . a generally cylindrical sheath 626 is longitudinally disposed around substantially all but the exposed tip 625 of tubular electrosurgical electrode 624 . electrode 624 is in fluid communication with the source of vacuum 250 for the aspiration of biodebris , for example , tissue , eschar , blood and / or other bodily fluids . during use , the open cell foam cover may be infused with a fluid ( not explicitly shown ) for example , water or saline solution . the fluid may increase the thermal mass of the covering and , additionally or alternatively , may provide a cooling effect . in this manner , an increase in surface temperature of the instrument shaft may be diminished or precluded , thereby reducing the risk of undesirable effects on adjacent anatomical structures . in fig7 a and 7b , there is shown an envisioned embodiment wherein a suction coagulator 700 includes an elongated shaft 720 that is supported by a housing 715 . the shaft 720 includes a tubular electrosurgical electrode 724 disposed longitudinally therethrough , the tubular electrosurgical electrode 724 having an exposed tip 725 for delivering electrosurgical energy to tissue . a generally cylindrical sheath 726 is longitudinally disposed around substantially all but the exposed tip 725 of tubular electrosurgical electrode 724 . at least one cooling lumen 770 is disposed longitudinally on the shaft 720 for delivering coolant c to the distal region , i . e ., electrode 725 of suction coagulator 700 . cooling lumen 770 is in fluid communication with a reservoir 790 via a conduit 795 . in embodiments , a connector 796 is provided for coupling a conduit 795 to cooling lumen 770 . reservoir 790 may contain a coolant , for example without limitation , saline or water . in use , coolant c may flow from reservoir 790 through conduit 795 , lumen 770 , and discharge from distal end 772 of lumen 770 . a valve ( not explicitly shown ) may be provided to regulate the flow of coolant . the valve ( not explicitly shown ) may be caused to be actuated by a user and / or by an automated controller , such as a processor . coolant c may flow from reservoir 790 via gravity feed ( i . e ., “ drip ” feed ) and / or by pressure feed provided by , for example without limitation , a centrifugal pump , a positive displacement pump , or a peristaltic pump ( not explicitly shown ). turning now to fig8 a and 8b , another envisioned embodiment of a suction coagulator 800 in accordance with the present disclosure is illustrated wherein a proximal housing 815 supports an elongated shaft 820 extending distally therefrom . a generally tubular cover 826 is longitudinally disposed around substantially all but an exposed tip 825 of a tubular electrosurgical electrode 824 that is disposed longitudinally through shaft 820 . a region 871 between cover 826 and electrode 824 defines a cooling jacket 872 that surrounds the tubular electrode 824 . as best shown in fig8 a and 8b , a cooling jacket 872 may include a cooling lumen 873 having a generally helical shape , and having an inlet port 870 and an outlet port 875 . the helical coils formed by cooling lumen 873 may form an open helix , wherein the helix pitch is greater than the outer diameter of the cooling lumen 873 , or a closed helix wherein the helix pitch is substantially equal to the outer diameter of the cooling lumen 873 . inlet port 870 is in fluid communication with a coolant source 790 via a conduit 795 . coolant c may be any biocompatible fluid , for example without limitation , saline , water , or air . coolant c may flow from coolant source 790 via gravity feed ( i . e ., “ drip ” feed ) and / or by pressure feed provided by , for example , a pump , as previously described herein . in one embodiment , coolant flows distally though the helical cooling lumen 873 until the distal end 878 of jacket 872 is reached . coolant c then flows proximally through a return lumen 874 to outlet port 875 , whereupon the coolant exits the suction coagulator 800 . in another embodiment , coolant c flow may be reversed from that described hereinabove , i . e ., coolant may flow initially to distal end 878 and thereafter proceed proximally through helical cooling lumen 873 , and subsequently , discharged from the suction coagulator 800 at outlet port 875 . in this manner , a cooling effect can be selectively biased towards a proximal end of the shaft or a distal end of the shaft as desired . for example , in use during an electrosurgical procedure such as an adenotonsillectomy , coolant c may be caused flow distally wherein fresh coolant is introduced to cooling jacket 872 at the proximal end thereof . thus a cooling effect may be biased toward a proximal end 830 of shaft 820 , which may be adjacent to , for example , anatomical structures unrelated to the electrosurgical procedure , such as the uvula and the oral commissure area , thereby reducing the risk of undesired effects to such areas . alternatively , cooling may be biased towards a distal end 831 of shaft 820 by causing coolant to flow proximally by introducing coolant c to cooling jacket 872 at the distal end thereof . in embodiments , the direction of coolant c flow may be selected by causing a reversing valve ( not explicitly shown ) that is in fluid communication with cooling jacket 872 to be actuated in a manner consistent with the desired direction of coolant c flow . fig9 a and 9b illustrate still another envisioned embodiment of a suction coagulator 900 in accordance with the present disclosure is illustrated , the suction coagulator including a distal housing 915 having extending distally therefrom an elongated shaft 920 . shaft 920 includes a cooling jacket 972 that is formed by the generally cylindrical region longitudinally disposed between a tubular electrode 924 and a tubular cover 926 . the cooling jacket is sealed at the distal end thereof by distal seal 960 and at the proximal end thereof by proximal seal 961 . a cooling supply lumen 970 is in fluid communication with the cooling jacket via an inlet port 962 provided by proximal seal 961 . during use , coolant c is admitted into cooling jacket 972 at the proximal end thereof , and thereafter flows distally . a distal return opening 963 is provided by cover 926 , or additionally or alternatively , by distal seal 960 . supply end 870 is in fluid communication with a coolant source 790 via a conduit 795 . coolant c may be any biocompatible fluid , for example without limitation , saline , water , or air . coolant c may flow to cooling jacket 972 via conduits 970 , 995 from coolant source 990 via gravity feed ( i . e ., “ drip ” feed ) and / or by pressure feed provided by , for example , a pump , as previously described herein . in one embodiment , coolant c flows distally though the cooling jacket 972 until the distal end 978 of jacket 972 is reached . coolant c then flows through distal return opening 963 , proximally through a return lumen 974 to outlet port 975 , whereupon the coolant exits the suction coagulator 900 . in another embodiment , coolant c flow may be reversed from that described hereinabove , i . e ., coolant c may flow initially to distal end 978 and thereafter proceed proximally through cooling jacket 972 , and subsequently , discharged from the suction coagulator 900 at outlet port 975 . the direction of coolant flow may be selectively reversed as previously described herein . the described embodiments of the present disclosure are intended to be illustrative rather than restrictive , and are not intended to represent every embodiment of the present disclosure . further variations of the above - disclosed embodiments and other features and functions , or alternatives thereof , may be made or desirably combined into many other different systems or applications without departing from the spirit or scope of the disclosure as set forth in the following claims both literally and in equivalents recognized in law .
an electrosurgical suction coagulator is disclosed having improved thermal insulation between the active electrode and adjacent tissue . in embodiments , passive insulation is used to control the transfer of thermal energy from an electrosurgical electrode into surrounding tissue . braided , closed - sell foam material , and open cell foam materials may be used to thermally insulate the outer surface of a suction coagulator shaft from an inner electrode . in embodiments , a suction coagulator shaft includes an external covering formed from open - cell foam material , which may be saturated with a coolant , such as water or saline , to increase the thermal mass of the shaft . in other embodiments , active cooling delivers coolant to the operative site . in yet other embodiments , a suction coagulator shaft includes a cooling jacket through which coolant is passed to actively cool the instrument . the improved electrosurgical suction coagulator disclosed herein may have a reduced operating surface temperatures which may result in reduced risk of undesirable effects to adjacent tissue , and may result in reduced operative times and improved patient outcomes .