Electrosurgical clamping device with insulation limited bipolar electrode

Abstract

An electrosurgical hemostatic instrument is provided in which the coagulation status of tissue engaged by two elements delivering an electrosurgical energy to tissue may be observed, and in which damage from thermal spread may be minimized. A preferred embodiment of the invention provides a bipolar endoscopic clamping, coagulation and cutting device. In this device, the outer conductive surface of the tissue engaging elements is substantially covered by an insulative coating which confines current flow to the clamped tissue and limited regions around the tissue engaging elements. Coagulation may be observed by watching the region around the tissue engaging elements. Coagulation around the tissue engaging elements may be controlled by selectively coating the outside of the elements with insulation to control current flow from the surface of the engaging elements.

What is claimed is: 
     
       1. A bipolar electrosurgical instrument comprising: an end effector located at the distal end of the instrument said end effector comprising:   first tissue grasping element including one or more outer electrodes and an electrically conductive tissue grasping surface wherein said tissue grasping surface on said first grasping element includes electrically conductive grasping teeth, said grasping teeth including an interior region and an exterior region, said exterior region being partially covered by said electrical coating; and   second tissue grasping element including one or more outer electrodes and an electrically conductive tissue grasping surface.