A CLINICAL-STUDY OF THE PARAMETERS AND EFFECTS OF TEMPORARY ARTERIAL-OCCLUSION IN THE MANAGEMENT OF INTRACRANIAL ANEURYSMS

TEMPORARY OCCLUSION OF intracranial arteries has emerged as a valuable technical adjunct in the management of intracranial aneurysms. The cu rrent study considered 121 patients (from a group of 234 consecutive a neurysm patients treated during a 2-yr period) who underwent elective temporary arterial occlusion. Twenty-one patients were excluded from f urther study because of an intraoperative rupture of an aneurysm, the elective sacrifice of afferent or efferent vessels, or the performance of an extracranial-intracranial arterial bypass graft; the remaining 100 patients underwent elective temporary occlusion under a standard n euroanesthetic regimen, including etomidate-induced burst suppression, normotension, normovolemia, and normothermia. In the postoperative pe riod, radiographic evidence of ischemic brain injury in the distributi on of the arteries occluded was selected as the end point for the fail ure of occlusion tolerance. The parameters evaluated with respect to t his end point included the duration and nature of the temporary arteri al occlusion, the number of the occlusive episodes, the specific vascu lar territory occluded, patient age, neurological status, presence of subarachnoid hemorrhage, vasospasm, and aneurysm size. Several paramet ers were found to be related to the postoperative development of ische mic injury. Patients more than 61 years of age and those in poor neuro logical condition (Hunt and Hess Grades III to IV) did not tolerate te mporary occlusion as well as patients who were younger and in better c ondition. Patients occluded for less than 14 minutes routinely tolerat ed the iatrogenic ischemia; the 95% confidence level for the toleratio n of occlusion without the development of infarction occurred at 19 mi nutes. All patients occluded for more than 31 minutes had both clinica l and radiographic evidence of cerebral infarction. In patients underg oing periods of occlusion greater than 14 minutes, the use of incomple te occlusion appeared to be associated with the development of cerebra l infarction. Relative, although not statistically significant, associ ations with poor tolerance of temporary occlusion were found with incr easing episodes of temporary occlusion and occlusion of perforator-bea ring segments of middle cerebral or basilar arteries.