The accident occurred only about 3 hours after the start of the twice around the clock race. Gidley, at the wheel of a Corvette DP, failed to avoid the slowing down GT Ferrari of Matteo Malucelli.
Both drivers were taken to the Halifax Health centre in Daytona, as officials red-flagged the race in order to clear the track.
"Memo Gidley (…) underwent surgical procedures on both his left arm and left leg last night," said a team statement.
"Gidley also has an unstable fracture in his back which will require additional surgery before he can be released from the hospital. He continues to be evaluated."
Malucelli is "awake and communicating" according to his team, but remains in hospital for observation.
Auto123.com wishes both of them a speedy recovery.