Electrosurgical instrument

An electrosurgical instrument comprising

• a support member;
• at least one electrode mounted on support member, said electrode comprising (a) a substrate consisting essentially of a material having a figure of merit of at least 0.15 at room temperature where said figure of merit is the product of the thermal conductivity, the heat capacity and the density of said material in the metric system, and (b) an electrically resistive coating disposed on said substrate, the volume resistivity of said coating extending from about 10.sup.-4 to 10.sup.8 .OMEGA.-cm;
• and
• means for connecting said electrode to a source of electrosurgical energy.

An electrosurgical instrument comprising

• a support member;
• at least one blade mounted on said support member, said blade having forward and rearward ends and comprising a material having a figure of merit of at least 0.15 at room temperature where said figure of merit is the product of the thermal conductivity, the heat capacity and the density of said material in the metric system where the cross section through a first plane perpendicular to the longitudinal axis of said blade has a first semi-elliptical configuration on one side of a second plane extending along said longitudinal axis of the blade from the forward to rearward ends thereof and a second semi-elliptical configuration on the opposite side of said second plane where the two major radii of said second semi-elliptical configuration are less than those of said first semi-elliptical configuration;
• and
• means for connecting said blade to a source of electrosurgical energy.

An electrosurgical instrument comprising

• a support member;
• at least one blade mounted on said support member, said blade having forward and rearward ends and comprising a material having a figure of merit of at least 0.15 at room temperature where said figure of merit is the product of the thermal conductivity, the heat capacity and the density of said material in the metric system where the cross section through a first plane perpendicular to the longitudinal axis of said blade has a first semi-elliptical configuration on one side of a second plane extending along said longitudinal axis of the blade from the forward to rearward ends thereof and a second semi-elliptical configuration on the opposite side of said second plane where said first and second semi-elliptical configurations are substantially equal in size and are offset with respect to one another along said second plane;
• and
• means for connecting said blade to a source of electrosurgical energy.