You know, that doesn't make any sense at all. I would take a lot of convincing before I believed that the hospital waited until relatives left and then dispatched the patients. That would take a level - a depth?- of concerted depravity that is not commonly found among a cross section of human beings.

It is far more likely that they were 'dispatched' in a last extremity of desperation.

I have not heard but I should imagine that after the patients were gone, the staff then saved themselves. Does anyone know? Surely they did not remain on the hospital premises?