NEW DELHI & SYDNEY & SINGAPORE--(BUSINESS WIRE)--Fitch Ratings has upgraded HCA Inc.'s (HCA) Issuer Default Rating (IDR) to 'BB' from 'BB-'. The Rating Outlook is Stable. A full list of rating actions follows at the end of this release. The ratings apply to $29.7 billion of debt outstanding at June 30, 2015. KEY RATING DRIVERS Industry-Leading Financial Flexibility: HCA's financial flexibility has improved significantly in recent years as a result of organic growth in the business as well as pr