TBH if I were the guy in the Hospital. I wouldnt give a damn about a letter. If I wasnt permanently damaged I wouldnt care to have any contact with you. If I was damaged I would try to sue you or others to get some money. If I was seriously disabled like my spine broken or something I would care even less and stick to videogames oxycontin and whores.
In all cases I would not care to get a letter. Its not that I would hold a grudge I simply wouldnt care what you wrote unless it has something to do with your unbearable guilt and the question " What can I do for you ?"
If you would be a hot girl I would want a letter though.