HOUMA -- A 26-year-old urologist is credited with helping save hundreds of New Orleans hurricane victims who spent days stranded on a highway overpass. Packing a stethoscope in one hand and a loaded handgun in the other, Scott Delacroix Jr. provided medical care and helped evacuate people stranded on Interstate 10 and Causeway Boulevard in Metairie during the days following Hurricane Katrina. His adventures are chronicled on a Web site and in the scribbled notes he made on the leather seats of his SUV. Delacroix, a New Orleans doctor now working at Leonard J. Chabert Medical Center in east Houma,...