Outcome analysis of carotid endarterectomy in Connecticut: the impact of volume and specialty.

The purpose of this study was to define the relationship between the surgeon's operative experience and specialty and the postoperative morbidity and mortality of carotid endarterectomy. All patients undergoing carotid endarterectomy (code ICD-9CM 38.12) in Connecticut between October 1985 and September 1991 were retrospectively identified. A total of 3997 carotid endarterectomies were performed by 226 surgeons in four specialties: general, cardiac, vascular, and neurosurgery. Individual surgeon volume ranged from fewer than one per year to 27.5 per year (mean 2.9 carotid endarterectomies per year). Outcome was measured as a combined stroke and/or death percentage. The average combined stroke and/or death rate for the entire group was 4.9%. The combined stroke and/or death percentage was influenced significantly by the surgeon's annual volume. Surgeons who performed one or fewer carotid endarterectomies (43% of total surgeons) were 2.5 times more likely (p < 0.002) to have a poor postoperative outcome than those who performed 10 or more per year (9.3% of total surgeons). Overall there was a statistically significant correlation between a surgeon's annual volume and outcome, particularly for general surgeons.