Metro Atlantans face risks of medical errors and life-threatening infections that are above national averages when they are admitted to some of the area's most prestigious hospitals, according to a study of new federal data. These conditions occur only a few times per year at most hospitals, according to the statistics, which cover Medicare patients treated between October 2008 and June 2010. Even so, the last thing hospital patients expect is that a hospital will make them sick. Or worse. The new data show most Atlanta hospitals had at least one case of a potentially deadly catheter-related bloodstream infection — commonly referred to as a "central line" infection — and Emory University Hospital posted the highest rate in the state and one of the highest in the nation, the report shows. In terms of numbers, not rates, the 36 central line infections reported at Emory gave it the fourth-worst ranking among about 3,300 hospitals in the nation. Other outliers included University Hospital in Augusta, which recorded the second-highest number of catheter-related urinary tract infections in the country with 77.