Prior to performing at Sea World, Bret Michaels rushed into surgery with acute appendicitis

[Amerigo Vespucci]

Bret Michaels never made it to the stage Sunday night in San Antonio, Texas.

Moments before he was due to perform at Sea World, doctors urged the former Poison frontman, 47 -- and current Celebrity Apprentice star -- to go to the hospital, his rep confirms to UsMagazine.com. He'd been suffering all day from severe stomach pains and what he thought was the flu.

But doctors determined Michaels had acute appendicitis, and rushed him into emergency surgery at 1 a.m. Monday morning.

"According to doctors, Michaels, who remains in the hospital, is doing well and beginning the recovery process," his rep tells Us.

Adds the rep, "Michaels, who has been known to perform under extreme conditions that would make most performers cancel, will unfortunately have no choice but to reschedule some of his April tour dates."

http://www.usmagazine.com/healthylifestyle/news/bret-michael-2010124