The Effect of Surgeon's Specialty and Volume on Perioperative Outcome of Carotid Endarterectomy

Abstract

Several studies have demonstrated better outcomes for carotid endarterectomy (CEA) at high-volume hospitals and providers. However, only a few studies have reported the effect of surgeons' specialty and volume on the perioperative outcome of CEA. This is a retrospective analysis of prospectively collected CEA data during a recent 2-year period. Surgeons' specialties were classified according to their board specialties into general surgeons (GS), cardiothoracic (CT), and vascular surgeons (VS). Surgeons' annual volume was categorized into low volume (<10 CEAs), medium volume (10 to <30 CEAs), and high volume (≥30 CEAs). The primary outcome was 30-day perioperative stroke or death, or both. Other perioperative complications were analyzed. Univariate and multivariate analyses were done to predict the effect of specialty/volume and any other patient risk factors on stroke outcome. A total of 953 CEAs were performed by 24 surgeons: 122 by 7 GS, 383 by 13 CT, and 448 by 4 VS. Patients' demographics and clinical characteristics were similar between specialties, except the incidence of coronary artery disease, which was higher for CT (P < .0001). The indications for CEA were symptomatic disease in 38% for VS, 31% for GS, and 23% for CT (P < .0001). The perioperative stroke and death rates were 4.1% for GS, 2.9% for CT, and 1.3% for VS (P = .1263). A subgroup analysis showed that the perioperative stroke rates were 5.3%, 2.3%, and 2.3% (P = .5112) for symptomatic patients and 3.6%, 3%, and 0.72% (P = .0992) for asymptomatic patients for GS, CT, and VS, respectively. Perioperative stroke rates were significantly higher for nonvascular surgeons (GS and CT combined) vs VS in asymptomatic patients (3.2% vs 0.72%, P = .0333). Perioperative stroke/death was also significantly lower for high-volume surgeons: 1.3% vs 4.1% and 4.3% for medium and low-volume surgeons (P = .0194; 1.3% vs 4.15% for high vs low/medium combined, P = .005, Fig). More CEAs were done for asymptomatic patients in the low-/medium-volume surgeons (78%) vs high-volume surgeons (64%, P < .0001), with a stroke rate of 4.6% for low-/medium-volume surgeons vs 0.51% for high-volume surgeons (P = .0005). A univariate logistic analysis showed that the odds ratio (OR) of having a perioperative stroke was 0.3 (95% confidence interval, 0.13-0.73; P = .0079) for high-volume surgeons, 0.4 (P = .0686) for VS, 0.2 (P = .0004) when patching was used, and 2.6 (P = .0521) for patients with preoperative renal insufficiency. A multivariate analysis showed that the OR of having a perioperative stroke for CT (vs VS group) was 1.8 (P = .269); for GS, 1.7 (P = .407); low-volume surgeons (vs high-volume), 3.1 (P = .073); medium-volume surgeons, 2.0 (P = .197); and for patching, 0.25 (P = .013, Table).TableMultivariate logistic analysis for perioperative stroke for specialty and volumeVariableOR95% CIPSpecialty CT vs VS1.80.64-4.98.269 GS vs VS1.70.47-6.51.407 Preoperative renal insufficiency2.40.89-6.25.083 Patching0.20.07-0.62.005Volume Low vs high3.10.90-10.76.074 Medium vs high2.00.70-5.76.197 Preoperative renal insufficiency2.50.92-6.56.073 Patching0.250.08-0.74.013 Open table in a new tab High-volume surgeons had significantly better perioperative stroke/death rates for CEA than low/medium-volume surgeons. Perioperative stroke/death rates were also higher for nonvascular surgeons, particularly in asymptomatic patients.