ouch this has to hurt
He was probably in shock (as stated above), his heart would have slowed down.
That, and\or the item in his arm would acually be stopping the blood from comming out.
If you ever get stabbed like that, leave the item in till you get to the ER. let them take it out, unless of course your a hardass and wanna race time to the ER before you passout from blood loss.
just my .02
I could be totally wrong =)

