EXECUTIVE SUMMARY: Certified registered nurse anesthetists (CRNAs) can practice independently or with varying degrees of supervision by physicians or anesthesiologists. Before 2001, the Centers for Medicare & Medicaid Services (CMS) conditions of participation required CRNAs to be supervised by a physician. Starting in November 2001, CMS implemented an opt-out policy to give states greater autonomy in determining how anesthesia services are delivered. The policy also provided a mechanism to increase access to anesthesia services.We sought to understand and describe surgical facility leaders' perceptions of CRNA quality, safety, and cost-effectiveness; the motivation and rationale for using different anesthesia staffing models; and facilitators and barriers to using CRNAs. We applied a mixed-methods approach to understand surgical facility leadership decision-making for staffing arrangements.The use of anesthesia staffing models differed by location and surgical facility type. For example, the predominantly CRNA model was used in only 10% of large urban hospitals but in 61% of rural ambulatory surgical centers. Interviews with surgical facility leaders revealed that geographic location, surgeon preference, and organizational inertia were powerful contributors to a facility's choice of staffing model. Other factors included the Medicare opt-out provision, facility experience, and cost considerations. Differences in quality and safety between models were not contributing factors for most facilities.
