Hospital and surgeon determinants of carotid endarterectomy outcomes

Background: Prior studies have found associations between surgeon and hospital case volumes and outcomes after carotid endarterectomy (CEA), but they have not simultaneously assessed the importance of a number of surgeon and hospital characteristics. Objective: To simultaneously assess associations between hospital case volume, teaching status, clinical trial participation, and surgeon specialty and case volume and the outcome after CEA. Design: Analysis of a large administrative database using logistic regression to correlate adverse outcomes after CEA with surgeon and hospital characteristics. Setting and Patients: A Canadian administrative hospital discharge database of all patients undergoing CEA in fiscal years 1994 through 1997. Main Outcome Measures: In-hospital stroke and/or death. Results: We found an inverse relationship between both hospital and surgeon case volumes and adverse outcomes. Teaching status had no association with outcome, but previous clinical trial participation predicted a better outcome. General surgeons fared worse than other specialists. Low-volume surgeons in low-volume hospitals had a relative risk of 3.5 for adverse outcomes compared with high-volume surgeons in high-volume hospitals. Conclusions: Several physician and hospital characteristics are determinants of outcome after CEA, but the negative effects of low hospital and surgeon case volumes, in particular, suggest that regionalization should be considered for CEA and that surgeons with low case volumes should not be performing CEA.