A surgical instrument, comprising a handle assembly including an approximation mechanism and a firing trigger； an elongated body portion extending distally from the handle assembly； a head portion disposed adjacent a distal end of the elongated body portion and including an anvil assembly and shell assembly supporting a plurality of staples, the approximation mechanism being actuable to move the head portion between spaced and approximated positions and the firing trigger being actuable to eject the plurality of staples from the shell assembly； and a safety mechanism disposed in mechanical cooperation with the handle assembly, the safety mechanism being movable from a first position preventing actuation of the firing trigger to a second position permitting actuation of the firing trigger, wherein the safety mechanism is moves from the second position to the first position in response to movement of the head portion from the approximated position towards the spaced position.
