Harrison Okene; a Nigerian man was trapped for nearly three days in 98ft deep, freezing sea water. He was on board the tug boat, Jascon-4 when the boat met with a mishap and sank upside down on the seabed. Since Harrison was trapped in an air pocket, he was able to breathe during the ordeal. He was the lone survivor out of the 12 on board.
He worked as a cook on board and was in the toilet when the mishap occurred. Fortunately, he was able to find an area with an air pocket which led him to survive. He was in the water in total darkness, thinking that the water would fill up the room in which he was trapped. But somehow, the water did not enter. He said he was hungry but more than that he was intensely thirsty. In his account to news reporters he said, that he could even hear the fish eating the dead bodies of his fellow crew members.
Harrison says that he is still unable to recover from the trauma and sometimes when he is asleep, he feels as if his bed is sinking and is in water and then he wakes up screaming.(source)