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Anesthesiology, V 128 • No 3 429 March 2018 H OW does one identify high-quality anesthetic care? Although the specialty of anesthesiology has succeeded in improving the safety and quality of care over time, with a 97% reduction in anesthesia-related deaths between 1948 and 2005, from 3.3 per 100,000 population to 1.1 per million,1,2 our ability to identify high-quality anesthesia care at the level of the individual provider or practice remains sharply limited. For example, hospitals that equate high-quality anesthesia with having high operating room efficiency may implement process measures such as the percentage of on-time first case starts to evaluate individual anesthesiologist performance, but these measures rarely have an impact on surgical outcomes.3,4 In this issue of ANESTHESIOLOGY, McIsaac et al.5 present new data with potential implications for how anesthesia quality is understood and measured by exploring patient outcomes across hospitals with distinct signatures of practice based on their utilization of neuraxial versus general anesthesia. McIsaac et al.5 studied a large population-based cohort of Canadian older adults receiving care for hip fracture, a condition that occurs more than 1.6 million times each year worldwide and is associated with high morbidity and mortality. Over a period of 14 years, among the more than 100,000 patients who underwent hip fracture repair, McIsaac et al.5 found that 53% received neuraxial anesthesia alone, with the vast majority of these cases receiving spinal anesthesia. The remainder received general endotracheal anesthesia, which was typically administered without a concurrent neuraxial technique. In adjusted models, McIsaac et al.5 observed no difference in survival when considering the anesthesia type administered to each patient. However, the authors observed a strong association between the fraction of cases at each hospital that received neuraxial anesthesia in the year before surgery and 30-day mortality, even after controlling for the specific type of anesthesia each patient received. The association of hospital neuraxial anesthesia use with survival was most pronounced at hospitals in the lowest quintile of neuraxial use, where patients had a 12% greater relative risk of dying within 30 days of surgery compared to patients in the second lowest quintile of neuraxial use prevalence. In contrast, there was only an additional 1% relative increase in survival among patients grouped across the other four quintiles of neuraxial anesthesia prevalence. What might explain this discrepancy? That is, why would a hospital’s anesthesia practice patterns in the previous year be associated with an individual patient having improved survival after hip fracture surgery? One possibility is that the “signature” of anesthesia practice at a given hospital may serve as a marker for other patient, provider, or institutional factors that affect survival above and beyond the specific type of anesthetic a patient receives. While the data of McIsaac et al.5 do not show patterns of utilization of neuraxial anesthesia to be correlated with other measurable differences in the quality of care, such patterns may point to underlying differences in skill among the surgeons or anesthesiologists practicing at hospitals with higher versus lower rates of neuraxial use. Alternately, factors not related to practitioner skill, such as the engagement and experience of other operating room staff, may affect both the likelihood that a given patient receives neuraxial anesthesia while also potentially affecting the quality and outcomes of care more generally. Do Anesthetic Choices Signal Quality?