Carotid Artery Stenting in the Nation: The Influence of Hospital and Physician Volume on Outcomes

Abstract

Objectives: To assess national outcomes of carotid artery stenting (CAS) with respect to hospital and practitioner volume.

Methods: The 2005 to 2006 Nationwide Inpatient Sample (NIS) was used to assess CAS with respect to hospital volume, physician volume, and associated complications. Results: Eighteen thousand five hundred ninety-nine CAS interventions were identified. The top 25% was used to define high-volume hospitals (>60 CAS/2 years) and practitioners (>30 CAS/2 years). The stroke rate after CAS was significantly different between low- and high-volume hospitals (2.35% vs 1.78%, respectively; P = .0206). The stroke rate after CAS was also significantly different between low- and high-volume practitioners (2.19% vs 1.51%, P = .0243). Hospital resource use varied significantly between low- and high-volume hospitals (length of stay [LOS]: 1.64 ± 2.10 vs 1.45 ± 11.21, P = .0006; total charges: $32 261 ± 20 562 vs $30 131 ± 19 592, P = .0047) and practitioners (LOS: 1.70 ± 2.14 vs 1.36 ± 1.36; P < .0001; total charges: $33 762 ± 21 081 vs $23 957 ± 19 713; P < .0001). Conclusions: This analysis demonstrates that hospital and physician volume are associated with outcomes and utilization after CAS. High-volume hospitals and practitioners were associated with lower procedure stroke rates and decreased hospital resource utilization.

Keywords

carotid artery stenting outcomes analysis complications volume analysis

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