Mistakes committed by doctors at hospitals kills about 15,000 old people every month in the U.S. Nearly 164,000 people or more than 13 percent of patients, who are covered under Medicare, have had issues of error by medical practitioners.

The errors, which include mistakes and those that are unavoidable, include surgical ones or at times problems like spreading an infection or when patients’ blood sugar levels are not on check. Nearly 44 percent of the errors could have been averted.

The Office of Inspector General at the Health and Human Services Department reported about 180,000 deaths a year in its latest report. "An estimated 13.5 percent of hospitalized Medicare beneficiaries experienced adverse events during their hospital stays," the OIG said in the report. "Hospital care associated with adverse and temporary harm events cost Medicare an estimated $324 million in October 2008," the report said.

"This report shows that hospital patients are being harmed by medical errors at an alarming rate. Unfortunately, most Americans have no way of knowing whether their hospital is doing a good job preventing medical errors," said Lisa McGiffert of Consumer Union, which publishes Consumer Voice said.

American Hospital Association has promised better patient care.

"Hospitals are already engaged in important projects designed to improve patient care in many of the areas mentioned in the report. We are committed to taking additional needed steps to improve patient care," Rich Umbdenstock, President of the Association said.