So sorry to hear about your brother.
I have had a somewhat similar experience...I was living with my two son's and my lovely little dog in a rented house, I had lived there for 6 years and loved the house. I returned to education and got my honours degree in social science and was due to do my MA in social work.
I had periods of depression..I was diagnosed bipolar in 1994..due to a manic/psychotic episode. Nine years on....I cannot explain what 'triggered' me but I suddenly began to believe I had been sexually abused when I was a child (I don't BELIEVE I was) but I was convinced I had been.
It all becomes vague, confusing and 'fast' (like a video was fast forwarding) from this point..I was definately manic for awhile.
I then started hearing things and seeing things that were not there. I had a car then and I was driving around fast and furious to churchyards and other 'strange' places.
My behaviour was alarming enough, by this point, for my youngest son to contact the mental health services, they attended but I appparently sounded reasonable to them (god knows how)..my son persisted and they sent a psychiatrist..who prescribed olanzapine ( I so wish they had sectioned me at this point, saved a lot of heartbreak).I took the olanzapine (was your brother given any drugs before his violent outburst?) I 'lost it completely' after taking the olanzapine.....I began damaging my own belongings..things that meant so much to me..I then smashed two windows in the kitchen and threw various foodstuffs around!
My son's 'left' and I totally trashed the house and smashed more windows..apparently when the police came I was sat on the wall at the front of the property with a red top on with the hood up 'chanting'.
I remember very little of all this only through others can I piece this much together..I only remember the 'speed' feeling, everything was moving so fast...totally out of control.
Your brother it sounds to me was going through something similar although he hurt himself and not property. It would be interesting to know what drugs,if any, he was given earlier on that day.
I was told mine was psychosis..although I feel I lost all control after taking the olanzapine... and to be totally honest I still don't feel anyone has adequately explained to me just what went wrong with my mind..perhaps they can't!
What I would say is be strong in your quest to find out what its all about....listen to your brother when he is lucid....insist the mental health services are thorough and that your brother is given the right medication BEFORE he leaves the hospital..your brother needs assurances that the chances of it happening again are minimal and that, when discharged,he is given adequate and continued support in the community.
I know SSRI's can cause mania when given to ppl with bipolar..I would check that out on-line.
I was left with hardly any support off the mental health services when I was discharged (so no-one saw what was happening)..my meds were not right...and I ended up on 'the streets' for almost a year.
4 years on my life is still 'mixed up' and due to all thats happened I feel I cannot be 'assertive' with the mental health services (they do not appear to take me seriously).. they get defensive (if challenged by me regarding meds) and I feel they do not give a damn about my welfare...I am not on a 'mood stabalizer' because my current psychiatrist believes I do "not need one" unless I go 'manic' ermmmmm last time that happened I eventually lost everything and I was totally unaware I was going 'manic'!
I am not a violent person I had never 'destroyed' property before..I shuddder at what I did still!
I hope your brothers 'episode' is a one-off...but never be complacent..use any support you can get for him and if the meds work 'stay on them' I was taken off lithium prior to my last episode because the pyschiatrist I had then believed it was making my 'arthritis' worse...I wish I had insisted I stayed on it..the physical pain is nothing compared to the mental pain of my last 4 years.
I hope the physical injuries are not too bad and he does not have any serious damage.
My thoughts are with you both....keep us posted..if you want to ask me any questions please feel free.
take care
emptysoul