"He is pushing his body insanely to the limits," said Dr. Murat Gunel, who headed Blaine's medical team. Gunel, an associate professor of neurosurgery at Yale University School of Medicine, and other medical experts, had monitored the 33-year-old illusionist's condition 24 hours a day.
Large crowds gathered all day Monday for a closer look at Blaine, who was submerged in an 8-foot snow globe-like tank on the plaza of Lincoln Center for the Performing Arts. He used an oxygen tube to breathe, and was fed and relieved himself by tubes.
Gunel said the challenge had caused liver damage, sharp pains in Blaine's feet and hands, some loss of sensation and rashes all over his body.
Blaine planned to put on chains and handcuffs, remove his oxygen tube and then escape while holding his breath longer than the record of 8 minutes, 58 seconds. The finale was to air live in a two-hour ABC special, "David Blaine: Drowned Alive," on Monday night.
Kirk Crack, the magician's trainer and diving expert, said if there were any signs that Blaine was becoming unconscious, divers would immediately jump into the tank, free him from the chains and bring him to the surface.
Blaine started training in December, with some help from Navy SEALS. He lost 50 pounds so his body would require less oxygen.
As early as the second day of his challenge, Gunel said, there was evidence that Blaine was suffering liver failure; the medical team consulted with medical experts at NASA before stabilizing his condition. Blaine's underwater environment is similar to the weightlessness experienced by astronauts in outer space, he said.
"I told him he needed to get out of the water, and he refused me," said Gunel. "He said he did not want to let the people down."
Gunel said Blaine had agreed to allow researchers at Yale to examine him after the stunt to see what they could learn about how the body responds to an underwater environment.
Blaine's previous feats included balancing on a 22-inch circular platform atop a 100-foot pole for 35 hours; being buried alive in a see-through coffin for a week; and surviving inside a massive block of ice for 61 hours, all of which were performed in New York. In 2003, he fasted for 44 days in a suspended acrylic box over the Thames River in London.

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