Can I sue my employer in WA state?

I was injured in by a demented resident in my health care facility. He pushed me over and I fell and hit my head on the bed. I am now in such pain that I have been missing work. My doctors are saying it’s possibly a slipped disk and I might need surgery. Now here is the issue this could have been prevented had my employer educated me on the fact that he was aggressive and hurt someone before. Also he was on a unit where people knew how to handle him, where as my unit was not at all equipped with the education to handle him. It seems they were negligent somehow.