There are no differences in patient outcomes when anesthesia services are provided by Certified Registered Nurse Anesthetists (CRNAs), physician anesthesiologists, or CRNAs supervised by physicians, according to the results of a new national study conducted by RTI International. The study, titled "No Harm Found When Nurse Anesthetists Work Without Supervision by Physicians," appears in the August issue of Health Affairs.

The RTI study examined nearly 500,000 individual cases and confirms what previous studies have shown:  CRNAs provide safe, high-quality care. The study also shows the quality of care administered is equal regardless of supervision.

Currently, the Centers for Medicare & Medicaid Services (CMS) prohibits Medicare payments to hospitals and ambulatory surgery centers when CRNAs provide anesthesia care in the absence of physician supervision. However, starting in 2001 CMS began allowing states to "opt out" of the Medicare physician supervision requirement for CRNAs. Since then 15 states-most recently California in 2009-have opted out.

The RTI findings demonstrate that the Medicare physician supervision rule for CRNAs is obsolete and unnecessary. The study compared patient outcomes in states where the supervision requirement is in place with patient outcomes in the 14 states that had opted out of the requirement between 2001 and 2005, and found that patient outcomes did not differ. "We find no evidence that opting out of the oversight requirement harms patients in any way," said study author Jerry Cromwell, PhD. "Based on these findings we recommend that CMS repeal the supervision rule."

"The results validate what we have known all along-that the quality of care and safety record of nurse anesthetists is of the highest caliber, regardless of physician supervision," said James Walker, CRNA, DNP, president of the American Association of Nurse Anesthetists (AANA). "The data clearly show that there has not been a disparity in care in states that have opted out of the supervision requirement. In fact, the opt-out states have given nurse anesthetists the opportunity to prove, beyond a shadow of a doubt, what patients are most interested in knowing, and that is whether anesthesia is equally safe when provided by CRNAs or their physician counterparts. I'm happy to emphatically report that yes, it is."

"Motivated by the safe, excellent care that nurse anesthetists provide, 15 governors have decided to opt out of the Medicare payment rule, choosing instead to allow hospitals to make their own decisions on anesthesia staffing. This growing trend continues as states recognize the excellent skills and high-quality care of nurse anesthetists," said AANA President-elect Paul Santoro, CRNA, MS. "This study should encourage other states to think critically about their healthcare needs and how nurse anesthetists can expand access to anesthesia services."

Other research and data support the RTI finding that there are no differences in quality of anesthesia services delivered by CRNAs and anesthesiologists. Most recently, a study about the cost effectiveness of nurse anesthetists released in May included a comprehensive review of published studies. The review found no measurable differences in the care provided by CRNAs and anesthesiologists. Equally important, the study showed CRNA-only anesthesia care to be the most cost-effective anesthesia-delivery model.

Methodology The study was conducted by Jerry Cromwell, PhD, and Brian Dulisse, PhD, for RTI International and was funded by the AANA. The study is based on 480,000 randomly selected surgical discharges from Part A and Part B Medicare data files from 1999 to 2005. The study compared adverse outcomes - specifically, mortality and complication rates - in opt-out and non opt-out states The study controlled for case complexity and patient characteristics. The authors are wholly responsible for the data, analysis, and conclusions.

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