Anesthetic considerations for cerebral aneurysm surgery

Both surgical and anesthetic perioperative management of patients undergoing cerebral aneurysm surgery have progressed dramatically in recent years. Early clipping of an aneurysm prevents rebleeding and allows rapid institution of hypertensive, hypervolemic hemodilution to prevent and/or treat cerebral vasospasm. Perioperative dehydration has been recognized as detrimental after subarachnoid hemorrhage. Similarly, the systemic hypotension routinely used to facilitate aneurysm clipping in the past has been supplanted by the use of temporary vascular occlusion of the feeding artery and induced hypertension to improve collateral blood flow to the potentially ischemic area. Moreover, because only a focal region of brain distal to the temporary clip is at risk for ischemic damage (as opposed to global effects from hypotension), ischemia monitoring can be targeted to specific areas. Deliberate mild hypothermia is frequently used for neuronal protection, and pharmacologic protective therapy can be potentially expanded with the availability of propofol and etomidate. This review examines the important advancements in perioperative management of ruptured intracranial aneurysms that have evolved in the last decade. The article also discusses the anesthetic management of endovascular aneurysm obliteration.