 Rupture of brain aneurysms is a common cause of death and disability, accounting for as many as 10 of stroke cases in the United States. While much of the resulting injury to the nervous system is caused by the initial bleeding from the aneurysm, many of these patients develop cerebral vasospasm, pathological constriction of the blood vessels supplying the brain, several days following hemorrhage. As many as a third of patients can suffer a resulting neurological deficit and stroke, presumably caused by the decreased blood flow to the brain ischemia. This delayed brain injury accounts for a significant percentage of poor outcomes following aneurysm rupture. Remote ischemic preconditioning by transient limb ischemia produced by inflation of a blood pressure cuff on the arm or leg has been shown to minimize ischemic injury to other organs, most notably the heart. This remote ischemic preconditioning has the promise of protecting the brain from ischemic injury. Whereas in other forms of stroke the onset of ischemia cannot be predicted in the general population, following aneurysm rupture the investigators know patients risk of developing vasospasm. Therefore, ischemic preconditioning following aneurysm rupture may help prevent some of the ischemic injury caused by vasospasm. One small study has shown decrease in vasospasm and metabolic products of ischemia in patients treated with remote ischemic preconditioning after subarachnoid hemorrhage. Decreased vasospasm due to remote ischemic preconditioning of the brain following aneurysm rupture still needs to be validated and question remains if that shows a mortality and morbidity benefit. 