Vestibular schwannoma surgical volume and short-term outcomes in Maryland

Objective: To characterize contemporary practice patterns and outcomes of vestibular schwannoma surgery. Design: Cross-sectional analysis. Setting: Maryland Health Service Cost Review Commission database. Patients: The study included patients who underwent surgery for vestibular schwannoma between 1990 and 2009. Main Outcome Measures: Temporal trends and relationships between volume and in-hospital deaths, central nervous system (CNS) complications, length of hospitalization, and costs. Results: A total of 1177 surgical procedures were performed by 57 surgeons at 12 hospitals. Most cases were performed by high-volume surgeons (47%) at highvolume hospitals (79%). The number of cases increased from 474 in 1999-2000 to 703 in 2000-2009. Vestibular schwannoma surgery in 2000-2009 was associated with a decrease in CNS complications (odds ratio [OR] 0.4; P<.001) and an increase in cases performed by intermediate-volume (OR, 4.2; P=.002) and high-volume (OR, 3.2; P=.005) hospitals and intermediate-volume (OR, 1.9; P=.004) and high-volume (OR, 1.8; P=.006) surgeons. High-volume care was inversely related to the odds of urgent and emergent surgery (OR, 0.2; P<.001) and readmissions (OR, 0.1; P=.02). Surgeon volume accounted for 59% of the effect of hospital volume for urgent and emergent admissions and 20% for readmissions. After all other variables were controlled for, there was no significant association between hospital or surgeon volume and in-hospital mortality or CNS complications; however, surgery at high-volume hospitals was associated with significantly lower hospital-related costs (P<.001). Conclusions: These data suggest increased centralization of vestibular schwannoma surgery, with an increase in cases performed by intermediate- and high-volume providers and meaningful differences in high-volume surgical care that are mediated by surgeon volume and are associated with reduced hospital-related costs. Further investigation is warranted.