Do you think that Brain Death is irreversible??

Can you considered a person totally dead if the doctors said that is brain death? how hard would it be to know that somebody that you love is in a ventilator and unconscious. Those situations are very hard and difficult, when a person is considered brain dead by the doctors is because there is no activity in the brain, althought the person is connected in a machine so it would keep the person organs and circulation active. In the medicine brain death is considered an irreversible coma, there has been a lot of controversy in this cases, in the united states is legal but for example in the state of New york and new jersey the heart and lungs most stopped before the person is fullied considered dead. By facts brain death is irreversible, some religions differ from this, but you cannot come back to life having brain death. Everybody have their opinions and some also may differ from this one, but what do you think?