Background: Of patients undergoing cardiac surgery in the United States, 15% to 20% are re-hospitalized within 30 days. Current models to predict readmission have not evaluated the association between severity of postoperative acute kidney injury (AKI) and 30-day readmissions.
Methods: We collected data from 2,209 consecutive patients who underwent either coronary artery bypass or valve surgery at 7 member hospitals of the Northern New England Cardiovascular Disease Study Group Cardiac Surgery Registry between July 2008 and December 2010.