O'Bannon was found unconscious in his hotel room at Chicago's Palmer House Hilton Hotel around 9:00 a.m. Monday morning. He was in town for a trade conference.
Paramedics rushed him to Northwestern Memorial Hospital and he was taken into surgery around 11 a.m. O'Bannon's wife, Judy, and daughter Jennifer flew to Chicago to be with the 73-year-old governor.
Lt. Gov. Joe Kenran, who was with O'Bannon, quickly returned to Indianapolis as officials looked into procedures for succession of power.