Las Vegas hospital patients can be protected if doctors and hospitals commit to do no harm. Others across the country have made that pledge. The New Hampshire Hospital Association in September launched a five-year campaign to stop hurting patients in ways that lead to complications, disability or death. The Tennessee Hospital Association pledged in 2009 to eliminate preventable harm, starting with a focused effort to reduce hospital-acquired infections. The University of Illinois Medical Center in Chicago has no tolerance for patients being injured or infected on its premises. Neither does Kent Hospital in Warwick, R.I. But Las Vegas hospital leaders seem resigned to patient-care problems, even after the Sun published the findings of its two-year investigation that found thousands of incidents of patient harm in Las Vegas hospitals in 2008 and 2009.