Which subarachnoid hemorrhages require nimodipine (nimodipine)?

From the Guidelines

Nimodipine is recommended for all patients with aneurysmal subarachnoid hemorrhage (aSAH) to reduce poor outcomes related to cerebral vasospasm. The standard regimen is 60 mg orally every 4 hours for 21 days, starting within 96 hours of hemorrhage onset 1. If the patient cannot swallow, the liquid from inside the capsule can be extracted and administered through a nasogastric tube. Blood pressure should be monitored closely during administration, as nimodipine can cause hypotension.

Key Considerations

• The medication works as a calcium channel blocker that specifically targets cerebral blood vessels, helping to prevent cerebral vasospasm which is a common and dangerous complication of subarachnoid hemorrhage 1.
• Vasospasm typically occurs 3-14 days after the initial bleeding and can lead to delayed cerebral ischemia and infarction.
• Nimodipine has been shown to improve neurological outcomes in patients with aneurysmal subarachnoid hemorrhage by reducing the incidence of cerebral vasospasm, though the exact mechanism may involve both vascular effects and neuroprotective properties 1.
• Consistent administration of nimodipine is suggested even in the setting of nimodipine-induced hypotension that can be managed with standard medical interventions 1.

Administration and Monitoring

• The standard regimen of 60 mg orally every 4 hours for 21 days should be maintained unless significant BP variability occurs, in which case temporary stoppage may be necessary 1.
• Blood pressure should be closely monitored during administration to manage potential hypotension.
• If the patient cannot swallow, alternative administration methods such as through a nasogastric tube should be considered.

Evidence Base

• The recommendation for nimodipine use in aSAH is based on the most recent guidelines from the American Heart Association/American Stroke Association 1.
• These guidelines emphasize the importance of preventing cerebral vasospasm to improve outcomes in patients with aSAH.
• While other calcium antagonists and routes of administration have been studied, the evidence for nimodipine remains the strongest 1.

From the FDA Drug Label

Nimodipine is indicated for the improvement of neurological outcome by reducing the incidence and severity of ischemic deficits in patients with subarachnoid hemorrhage from ruptured intracranial berry aneurysms regardless of their post-ictus neurological condition (i.e., Hunt and Hess Grades I-V).

Nimodipine is required for subarachnoid hemorrhages from ruptured intracranial berry aneurysms, regardless of the patient's neurological condition, which includes Hunt and Hess Grades I-V 2.

• The indication is specific to subarachnoid hemorrhage from ruptured intracranial berry aneurysms.
• The severity of the hemorrhage can range from Hunt and Hess Grades I-V.
• There is no restriction on the use of nimodipine based on the size or location of the aneurysm, as long as it is a ruptured intracranial berry aneurysm.

From the Research

Subarachnoid Hemorrhages Requiring Nimodipine

• Subarachnoid hemorrhages that are complicated by cerebral vasospasm are likely to require nimodipine, as it has been shown to reduce the incidence of ischemic complications following aneurysmal subarachnoid hemorrhage (SAH) 3, 4.
• Patients with aneurysmal SAH who are at risk of developing cerebral vasospasm, such as those with a high Hunt and Hess grade, may benefit from nimodipine treatment 3.
• Nimodipine may be particularly beneficial when started within 24 hours of the hemorrhage, as it has been shown to be more effective in cases where treatment is started early 3.
• The use of nimodipine in patients with SAH who are treated with endovascular coiling may also be beneficial, as it has been shown to reduce the rate of cerebral vasospasm and delayed cerebral ischemia 5.

Administration of Nimodipine

• Nimodipine can be administered intravenously or perorally, with no significant difference in efficacy between the two routes of administration 6.
• The standard dose of nimodipine is 60 mg every 4 hours, but dose reductions may be necessary in some patients due to systemic arterial hypotension 7.
• The pharmacogenomic relationship of nimodipine dose reduction with clinical outcomes is an area of ongoing research, and may have implications for future individualized dosing of nimodipine 7.

Clinical Outcomes

• Nimodipine has been shown to improve clinical outcomes in patients with aneurysmal SAH, including reducing the incidence of delayed ischemic neurological deficits (DINDs) and improving Glasgow Outcome Scale scores 3, 4, 6.
• The use of nimodipine in patients with SAH may also reduce the rate of cerebral vasospasm and delayed cerebral ischemia, as measured by transcranial Doppler ultrasonography and MRI 5, 6.