A bipolar forceps for sealing tissue includes an elongated shaft having opposing jaw members at a distal end thereof, each of the jaw members including an electrically conductive sealing surface. The jaw members are movable relative to one another from a first position wherein the jaw members are disposed in spaced relation relative to one another to a second position wherein the jaw members cooperate to grasp tissue therebetween. The bipolar forceps is connected to a source of electrical energy such that the jaw members are capable of conducting bipolar energy through tissue grasped therebetween to effect a seal. The distance between the electrically conductive sealing surfaces when tissue is held therebetween is adjusted based upon a sensed pre-surgical condition during activation.