Returning to the United States in 1966, Sloane opened a community health center in Louisville's mostly black West End.
He also developed Louisville's first emergency ambulance squads and was active in leading local efforts against air pollution.
During his first term Louisville was hit by a tornado during the Super Outbreak on April 3, 1974, and faced a strike by sanitation workers that same year.
In 1981 Sloane ran for a second term as mayor and won, defeating Republican nominee Louie R. Guenthner Jr., a member of the Kentucky House of Representatives, by almost a two to one margin.
In 1991, with his term as judge-executive at an end, Sloane left Louisville to work on health care projects in Washington, D.C.
In 2023 Sloane published Riding The Rails, My Unexpected Adventures In Medicine, City Hall and Public Service.