Seven of 120 aneurysm patients admitted to the Henry Ford Hospital from October 1978 to August 1981 had giant internal carotid artery aneurysms that were treated by a combined internal carotid artery occlusion and extracranial-intracranial anastomosis. Three of these patients developed postoperative ischemic complications during the progressive closure of the carotid artery. These complications included the transient onset of syncope, hemiparesis, hemisensory deficits, and dysphasia. These complications resolved after the clamp was reopened and/or intravenous heparin was given. The possible mechanisms involved in the development of ischemia included the development of emboli at the occlusion site or inadequate flow originating from the area of the anastomosis. Prolonged occlusion of the vessel over a 7- to 10-day course with concurrent administration of intravenous heparin is recommended.