Bipolar coagulation apparatus and method for arthroscopy

Abstract

A bipolar blood coagulator probe has a coaxial or other bipolar arrangement for use submerged in a sterile fluid during arthroscopy of joints, with an elongated outer electrode positioned in juxtaposition to an elongated inner electrode and with an elongated electrical inner insulation layer positioned between the outer electrode and the inner electrode. The outer electrode, inner electric, and inner insulation can be concentric to each other or in other configurations, including sandwiched or laminated together. The bipolar probe also has an elongated outer electrical insulation sleeve over the outer electrode and a proximal end outer housing terminating in a plug with two prongs that are electrically connected in the housing to outer electrode and inner electrode. The prongs of the plug are adapted to plug into a suitable receptacle for connection to an RF generator. The distal ends of the outer electrode, inner insulation layer, and inner electrode of the bipolar probe extend longitudinally a distance beyond the distal end of the outer insulation sleeve to leave a length of exposed surface of the outer electrode. Positioning the surface of the exposed portion of the outer electrode in contact with the tissue near a bleeding blood vessel with the inner electrode a distance spaced away from the tissue in the sterile fluid and applying RF power results in initial coagulation of blood and denaturing of a small amount of surrounding tissue, which is a self-limiting process that prevents excessive necrosis. The probe can also be used with some or all of the distal ends of both of the electrodes or just one of the electrodes in contact with tissue that is submersed in the sterile fluid and is to be necrosed or with blood that is to be coagulated during arthroscopy.