On July 31, 2008 the Centers for Medicare & Medicaid Services (CMS) added three new "hospital-acquired conditions" (HACs), in the final rule for the Medicare acute care inpatient prospective payment system (IPPS):

• Surgical site infections following certain elective procedures, including certain orthopedic surgeries, and bariatric surgery for obesity;
• Certain manifestations of poor control of blood sugar levels; and
• Deep vein thrombosis or pulmonary embolism following total knee replacement and hip replacement procedures.

These conditions will incur a lower Medicare reimbursement rate unless patient records show the condition was "present on admission" (POA). The eight previously selected HACs are: object left in surgery; air embolism; blood incompatibility; catheter-associated urinary tract infection; pressure ulcers; vascular catheter-associated infection; surgical site infection – mediastinitis after CABG (coronary artery bypass graft); and falls (and additional injuries). Hospitals began reporting on these in October 2007, for payments starting October 2008.