April 13 (Reuters) - The S&P 500 opened nearly flat on Tuesday as data showed consumer prices increased by the most in more than 8-1/2 years in March, while Johnson & Johnson slipped as federal health agencies recommended pausing the use of its COVID-19 vaccine. The S&P 500 opened higher by 2.11 points, or 0.05%, at 4,130.10, while the Nasdaq Composite gained 52.45 points, or 0.38%, to 13,902.45 at the opening bell. The Dow Jones Industrial Average fell 24.24 points, or 0.07%, at the open to 33,721.16. (Reporting by Medha Singh in Bengaluru; Editing by Maju Samuel)