Dear Bill,
This must be awful for you to deal with.
I have had no experience of my parents attempting this - so far. We recently moved house and my father became very disoriented for the first couple of weeks and actually tried to hit me! Since he's been such a mild manner chap all of his life, it was totally out of character.
All I can think of at this stage is to suggest that you hide all sharp objects, like kitchen knives, needles, nail files and scissors, etc. This is what I did until my father settled down. Fortunately, he's back to his usual placid self again - but it was a bit disconcerting at the time.
I wonder if your wife has attempted to mutilate herself in times when she has been lucid? These are the moments that I find the hardest and most distressing to cope with. What can you say? Unfortunately, these periods are very hard to deal with and totally random.
Sorry I can't be of more help. Jude