A coating system comprising at least one layer made at least essentially of ZrO.sub.2 which is used for providing insulating properties to parts of medical devices, particularly of electrosurgical devices.

A medical device includes a body and at least one electrode disposed thereon. The electrode includes a metallic substrate, such as a platinum group metal, an alloy of platinum group metals, or gold. The surface of the substrate is modified in a manner that increases its effective surface area without inducing bulk heating. For example, the surface of the substrate can be laser textured and/or coated, such as with titanium nitride or iridium oxide.