OPTIMAL OUTCOME FOR HIGH-RISK CAROTID ENDARTERECTOMY

While carotid endarterectomy (CEA) can often be accomplished with a ve ry low stroke risk, certain scenarios-prior ipsilateral stroke, contra lateral carotid occlusion, or acute cerebral ischemia-have been associ ated with neurologic morbidity and mortality rates exceeding 10%. The routine use of temporary intraluminal carotid shunts has been thought to he obligatory in such patients, notwithstanding the fact that these devices are obtrusive and may be associated with an increased risk of perioperative stroke. Among 175 patients undergoing CEA, 68 could be classified as ''high-risk'' (contralateral carotid occlusion, n = 24; prior ipsilateral stroke, n = 28; acute cerebral ischemia, n = 16). CE A was performed under regional or local anesthetic block in all 68 pat ients. Sixty-six patients (97%), including 22 of 24 (92%) with contral ateral carotid occlusion, underwent CEA (carotid occlusion times avera ging 22 minutes [range: 12 to 42 minutes]) without insertion of a caro tid shunt. Two patients (2.9%) with contralateral carotid occlusion lo st consciousness ? and 10 minutes after carotid clamping, but regained neurologic normalcy after shunt insertion. A single patient (1.5%) ex perienced a fatal stroke due to heparin-induced ''white clot'' syndrom e. Rates of shunt insertion and of perioperative stroke did not differ from those in 107 ''low-risk'' CEA patients. Cerebral collateral circ ulation is well developed even in compromised CEA patients. The necess ity for temporary carotid shunts may be reduced by the use of ''awake' ' anesthesia in such cases. Carotid shunting may be no more necessary, and operative outcome no less favorable; in ''high-risk'' than in unco mplicated CEA patients.