Management of cervical bruits and carotid stenosis in preoperative patients.

A PERIOPERATIVE STROKE is one which occurs intraoperatively or in the several days following an operation. It occurs in 0.3% of general surgical patients, in about 1% of patients undergoing peripheral vascular reconstruction (PVR), and in 1-5% of patients undergoing coronary artery bypass grafting (CABG). An aggressive approach to the detection, evaluation and treatment of asymptomatic cervical bruits and carotid stenosis in preoperative patients has been recommended in an effort to prevent perioperative stroke. ~ This approach is based on the often unstated assumption that perioperative stroke is mediated by untreated carotid occlusive disease potentiated by intraoperative hypotension resulting in stroke. ~' Although this scenario of perioperative stroke and its prevention is intuitively reasonable, justification for prophylactic carotid endarterectomy (CE) in preoperative patients requires critical review of four issues: 1. What is the prevalence of asymptomatic carotid occlusive disease in preoperative patients? 2. Can subgroups of preoperative patients with increased risk of perioperative stroke be effectively identified? 3. What are the mechanisms of perioperative stroke in these subgroups (and, consequently, is prophylactic CE likely to be effective)? 4. Is the morbidity and mortality of prophylactic CE in these patients less than the perioperative stroke risk in patients who do not undergo prophylactic CE? Patients undergoing PVR (including abdominal aortic surgery) and CABG are often considered to be at special risk of perioperative stroke on the basis of associated atherosclerotic carotid disease. We review the predictive value of cervical bruit and stenosis for perioperative stroke in CABG and PVR patients. Potential differences in stroke prevalence and mechanism in these two groups necessitates their separate analysis. Based on aggregate data, an approach to management is suggested and the specific issues requiring further study are defined.