For David Blaine, danger is a way of living. In other words, life without danger is a waste of time. Magician and illusionist David Blaine will be hanging upside down for a long time without a safety net 50 feet above New York’s Central Park. He will be hanging in the position for about 60 hours.

Dr. Massimo Napolitano of the Hackensack University Medical Center in New Jersey told the Bergen Record that hanging upside down for a long time increases blood pressure in the head, especially in the eyes. That could lead to blindness.

“My biggest concern for him is possible clotting in the veins of his eyes, causing blindness,” Dr Napolitano told the paper.

Dr. Napolitano says there is a risk of swelling and cramps in internal organs and clots in the veins of the eyes.

“If I listened to what all the doctors told me, I wouldn't have done any of the things that I’ve done,” Blaine said, as quoted by the Daily News. “The human organism can endure much more than we think we can.”

Blaine’s previous challenges include holding his breath for more than 17 minutes in a water tank, spending 63 hours encased in a block of ice in Times Square and fasting for 44 days while suspended above the Thames.

On April 30 he left his audience breathless by staying underwater and holding his breath for 17 minutes and 4 seconds on “The Oprah Winfrey Program.” After the stunt, Blaine told Winfrey that breaking the record was “a lifelong dream,” although he was hoping to make it for 23 minutes.