> Without oxygen the brain can only survive for about 5 minutes before the damage is irreversible. > > However, at lower temperatures, cells need less oxygen be

> Without oxygen the brain can only survive for about 5 minutes before the damage is irreversible. > > However, at lower temperatures, cells need less oxygen because all chemical reactions slow down. While it may imply you can "restart" a body, it isn't what the article is saying. Simply the brain is running in a state where oxygen utilisation is so low, that it can survive without an external supply for periods of more than an hour (but definitely not for long periods). And, by replacing the blood, patients can be brought to this state much faster than other techniques.