Quality Nursing Care Act of 2004 - Amends title XVIII (Medicare) of the Social Security Act, as amended by the Medicare Prescription Drug, Improvement, and Modernization Act of 2003, to require under new Medicare part D (Voluntary Prescription Drug Benefit Program) that each participating hospital adopt and implement a staffing system that ensures a number of registered nurses on each shift and in each unit of the hospital to ensure appropriate staffing levels for patient care. Outlines whistle-blower protections.