A surgical cutting and stapling instrument has an improved blade. The surgical instrument has a handle with a moveable firing trigger, a shaft extending from the handle, and a stapling head at the end of the shaft. An array of staples are located within the stapling head. An anvil is coupled to the stapling head and has staple forming pockets facing and in alignment with the staples. A breakaway washer is located within the anvil assembly and has a pair of parallel spaced walls with a thin web extending therebetween. The thin web faces the distal face of the stapling head. A blade is located within the distal face of the stapling head and has a distal cutting edge and at least one wedge spike facing the annular thin web of the breakaway washer. When the anvil is moved adjacent to the stapling head and the firing trigger is closed, the staples are formed and the blade is moved to sever the breakaway washer in a two step process. First, the wedge spike of the blade penetrates the thin web of the breakaway washer and weakens the thin web by propagating a crack within the thin web. Second, once the breakaway washer is cracked, the distal cutting edge of the blade severs the thin web.