Is it possible to return from the dead ?

Dr. Sam Parnia has taken a closer look at how someone can be revived up to several hours after death. The key is in determining at what point the patient is actually dead and at what point it becomes impossible to revive them. It is now believed that the brain cells remain viable for as long as eight hours after a person is otherwise declared clinically deceased, but finding a reliable way to resuscitate someone within this time frame remains a problem that science has yet to solve. "We now understand that it’s only after a person has turned into a corpse that their cells are undergoing death, and if we
therefore manipulate those processes, we can restart the heart and bring a person back to life," said Parnia. Dr. Sam Parnia, a critical care doctor and the director of resuscitation research at Stony Brook University School of Medicine, has written a new book discussing ways in which people can be resuscitated after they previously would have been considered clinically dead.

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