Never be alone after a head injury.

Note: I am trying to update this with best practices but some comments on here, below will provide more practical advice than me.  Never, ever, ever go to sleep with a possible concussion brain bleed.

The details about Bob's death were released:

"The authorities have determined that Bob passed from head trauma. They have concluded that he accidentally hit the back of his head on something, thought nothing of it and went to sleep," the statement said. "No drugs or alcohol were involved."

Thats all it took for a legend of comedy to disappear from this earth.  Next time you hit your head at night, take a second to remember Bob.  Dont be alone. 

Updates with potentially relevant advice:  “If you have a head injury, you never — and I mean never — be by yourself for the first 24 hours,” said Dr. Gavin Britz, the chair in neurosurgery at Houston Methodist.  Dr. Britz said that he would counsel people who get a significant knock to the head to see a doctor or, short of that, to ask someone to track their symptoms and even wake them up occasionally at night for monitoring.