An electrosurgical instrument having active and return electrodes with a movable suction sheath for variable fluid and debris removal during surgical procedures is disclosed. The suction apparatus has an outer sheath that is external to a shaft to provide a lumen. The sheath assembly is axially movable relative to the fluid aspiration element between first and second positions for treating the target site and fluid and debris removal, respectively. The first position positions the distal end of the shaft axially distal to a leading edge of the sheath assembly. The second position positions the distal leading edge of the sheath assembly axially adjacent to the end of the shaft. The fluid aspiration element comprises an inner lumen extending through the shaft, and at least one port extending radially through the shaft. The port is in communication with the inner lumen. A vacuum provides suction through the port and inner lumen.