A Modern Appraisal of Outcomes Associated with Carotid Endarterectomy Performed Using General and Regional Anesthesia

Background: Carotid endarterectomy (CEA) remains the most definitively proven method of treating extracranial carotid occlusive disease. The current analysis involves direct, retrospective comparison of perioperative outcomes among patients undergoing CEA for high grade extracranial carotid stenosis, stratified according to intraoperative anesthetic method.
Methods: All patients undergoing CEA between January 1998 and December 2006 were identified from a prospectively maintained registry. Patients were grouped according to modality of operative anesthesia (general versus regional). Primary end-points included perioperative (30 day) stroke, death, myocardial infarction and pulmonary related events. Evaluation for myocardial infarction was initiated based upon clinical suspicion for myocardial event. Secondary end points included cranial nerve injury, hematoma, amaurosis fugax, transient ischemia and length of stay. Statistical analysis was performed using chi square analysis, Fisher's exact and Kruskal-Wallis tests. P-value < 0.05 was used to indicate statistical significance.
Results: Six hundred seventy nine patients underwent CEA (234 (34.5%) under general anesthesia vs 445 (65.5 %) using regional anesthesia). Three hundred ninety-two patients (57.8 %) were asymptomatic relative to their carotid stenosis. Perioperative incidence of stroke among all patients was 2.2% with a significant difference observed among patients receiving regional anesthesia (1.4%) compared to general anesthesia (4.2 %), (p<0.02). Observed incidence (%, general vs. regional) of myocardial infarction (0.4 vs 0.7; p=0.72), and pulmonary related events (0.9 vs 1.1; p=0.80) was not significantly different between the two groups. No perioperative deaths occurred among patients receiving regional anesthesia compared to an observed incidence of 0.4 in patients receiving general anesthesia. Overall incidence of perioperative complications was significantly less among patients receiving regional anesthesia, (12.9 vs 7.5, p<0.03). With the exception of median hospital stay (days: general (2) vs regional (1), (p<0.0001)), analysis of secondary end points failed to reveal a significant difference based on anesthetic technique relative to the incidence (%, general vs regional) of cranial nerve injury (2.6 vs 0.9; p=0.08), hematoma (1.3 vs 1.1; p=0.80), and postoperative amaurosis fugax or transient ischemia (0 vs 1.1; p=0.12).
Conclusions: Carotid endarterectomy remains an effective method for treating carotid bifurcation stenosis and may be performed safely using general or regional anesthesia. Regional anesthesia is associated with improved perioperative outcomes in relation to stroke and overall observed complication rates.