Magician David Blaine's doctor is concerned that his latest stunt may irrevocably damage his health.

Blaine is still hanging upside-down in New York Central Park and Dr Ronald Ruden, who has advises him on all of his challenges said he was particularly concerned about blood clots and blindness.

He said: "We get into real trouble because if he throws a clot or he breaks a blood vessel in his brain, there is nothing stopping it. So we just have to hope it doesn't happen because if it happens it will literally be a tragedy for David."


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The daredevil plans to be suspended like a bat at a height of 44 feet for 60 hours. He will finish the stunt with a spectacular plunge to the ground.

Blaine, who has made a name for himself by pushing the limits of human endurance, will abstain from eating and sleeping for the duration of the challenge but will drink fluids.

Two hours after being hoisted upside-down, Blaine looked uncomfortable. He could be seen stretching his legs and pulling himself up to a horizontal position about every five minutes to boost his circulation.

"I thought it was going to be pretty bad but it's probably worse than I anticipated," said Blaine.

Past stunts have included holding his breath under water for more than 17 minutes, fasting for 44 days while suspended in a glass box over the River Thames in London and surviving in a block of ice for more than 60 hours.

The secret, he says, is to take things minute by minute, not contemplating the remaining time he must spend in discomfort.

"I think the hardest part of this is going to be sleep-deprivation plus keeping blood flow. I guess the other factor that we didn't consider is heat from the sun. That'll need to be considered," said Blaine, grunting with discomfort.