Most brick wall damage can be left alone without affecting the firing results. In some cases, you can use high temperature element pins to hold broken bricks together:
1) Squeeze the "U" section of two element staples with pliers. This will straighten the curve in the element staple so that instead of a "U" shape, the short section of staple will be straight. This prevents the staples from gouging too deeply into the brick.
2) Fit the broken brick piece back into the wall where it fell out.
3) Grasp an element staple with pliers, and press the staple at an angle into the broken brick piece. Use two staples titled away from each other. (Pressing the staples in at an angle holds the broken brick better than pressing the staples straight in.) Be careful to avoid pressing a staple into an element. The staple should also be short enough so that it does not touch the kiln case on the other side of the brick wall. (This idea is courtesy of Tony Rodriguez of GSM Enterprises in San Antonio, Texas.)