Anesthesia for cerebral aneurysm surgery: Use of induced hypertension in patients with symptomatic vasospasm

A primary goal of the anesthetic management of patients undergoing craniotomy for cerebral aneurysm surgery is to prevent rupture or rerupture of the aneurysm by careful maintenance of its transmural pressure. Induced hypotension is often used to aid in this transmural pressure control. It can, however, pose a high risk of cerebral infarction if used in the first few days after SAH in patients with underlying arterial narrowing due to vasospasm, disrupted cerebral autoregulation, and impaired perfusion reserve, even if not clinically evident. While the exact risk of infarction in this setting is not known, many patients with angiographic spasm awaken with new deficits not attributable to sacrifice of vascular structures. Two recent cases in which cerebral aneurysms were clipped to eliminate the risk of rebleeding using induced hypertension as part of the anesthetic technique to continue treatment of ischemic symptoms of vasospasm are described.