Chapter 4 Aneurysmal Subarachnoid Hemorrhage Trials

Publisher Summary This chapter discusses aneurysmal subarachnoid hemorrhage (SAH) trials. Intracranial aneurysm rupture is the most common identifiable cause of nontraumatic SAH. Although the case-fatality rates from SAH have progressively declined, the incidence of SAH, unlike other types of stroke, has not declined over time. The outcome of patients remains poor, despite rapidly evolving research regarding diagnosis, causes, and the treatment of SAH. The overall mortality rate is estimated to be 25%. Approximately 50% of patients who survive the aneurysmal rupture will have significant morbidity for approximately 30% of which secondary ischemia is responsible. Cerebral vasospasm after aneurysmal SAH is a major cause of disability and death. Therefore, because little can be done to ameliorate the immediate deleterious effect of aneurysm rupture, rebleeding and vasospasm are the major problems for which clinical trials have been designed. Large, multicenter prospective cohort analyses and multicenter prospective randomized trials have influenced considerably the treatment protocols for SAH patients. Nevertheless, many currently accepted treatment options are not supported by rigorous clinical scientific evidence. Some specific treatments for SAH are not amenable for testing by randomized, prospective trials because of practical or ethical considerations.