BACKGROUND: Neuraxial anesthesia (NA) is increasingly recommended for lower extremity joint replacements as some studies show that on the individual level it may be associated with improved outcomes. However, as hospital-level studies are lacking we attempted to elucidate the relationship between hospital-level NA utilization and outcomes. If such a relationship exists, implications may be far-reaching for the >1 million annual joint replacements performed in hospitals throughout the US.
METHODS: We utilized the nationwide Premier Perspective database (2006-2014; 550 hospitals) including 354,894 hip [THR] and 766,100 total knee [TKR] replacements. Multivariable associations were measured between hospital-level use of NA (dichotomized and subgrouped into quartiles [Q1-4]) and outcomes. Outcomes included: respiratory and cardiac complications, blood transfusion and intensive care unit (ICU) need, opioid utilization, and length and cost of hospitalization. Odds ratios (OR) and 95% confidence intervals (CI) are reported.
RESULTS: Overall, 151 (27%) of hospitals did not use NA for these cases. NA utilization was 0-4% in Q1 and 49-97% in Q4. Particularly among TKR patients, hospital-level NA utilization (compared to hospitals without NA use) was associated with up to 24% decreased odds for respiratory and cardiac complications in Q1 (OR 0.76 CI 0.66-0.88 and OR 0.76 CI 0.63-0.92; both P<0.05). However, the most consistent volume effects were seen for cost of hospitalization: -19% and -17% decreased costs in Q4 of NA utilization for TKR and THR, respectively.
CONCLUSION: Hospitals that use NA (versus those that don’t), are associated with lower hospitalization cost for lower joint replacements. This may be partly due to lower odds for adverse outcomes, particularly in TKR patients. Our findings may point towards an important role of neuraxial anesthesia not only as a modifiable risk factor for outcomes on a patient level, but potentially to its suitability as a quality indicator amongst hospitals performing lower joint replacements. Further research and maturation of this field of research is needed before firm conclusions can be drawn.