Nimodipine and SAH

Q: "Nimodipine" is the standard of care in patients after Sub-Arachnoid-Hemorrhage (SAH) to prevent vasospasm as it showed to decrease the incidence of either angiographic or symptomatic vasospasm. (Select one)

A) True
B) False


Answer: False

Enteral Nimodipine is the standard of care in patients with SAH. Due to its calcium-channel-blocker activity, it is assumed to prevent vasospasm and to have a vasodilatory effects on cerebral vessels. But, six major studies 1-6 over the span of 15 years failed to provide a convincing evidence that nimodipine decreases the incidence of either angiographic or symptomatic vasospasm. Despite that, Nimodipine has shown to improve outcomes in SAH in multiple studies 5-7. Various alternative explanations have been put forward for its mechanism of action including

• reduction of calcium-dependent excitotoxicity
• decrease platelet aggregation
• dilation of small arteries not visible on angiograms
• inhibition of ischemia triggered by red blood cell products

References:

1. Allen GS, Ahn HS, Preziosi TJ, et al. Cerebral arterial spasm--a controlled trial of nimodipine in patients with subarachnoid hemorrhage. N Engl J Med 1983; 308:619. 

2. Philippon J, Grob R, Dagreou F, et al. Prevention of vasospasm in subarachnoid haemorrhage. A controlled study with nimodipine. Acta Neurochir (Wien) 1986; 82:110. 

3. Petruk KC, West M, Mohr G, et al. Nimodipine treatment in poor-grade aneurysm patients. Results of a multicenter double-blind placebo-controlled trial. J Neurosurg 1988; 68:505. 

4. Pickard JD, Murray GD, Illingworth R, et al. Effect of oral nimodipine on cerebral infarction and outcome after subarachnoid haemorrhage: British aneurysm nimodipine trial. BMJ 1989; 298:636.

5. Barker FG 2nd, Ogilvy CS. Efficacy of prophylactic nimodipine for delayed ischemic deficit after subarachnoid hemorrhage: a metaanalysis. J Neurosurg 1996; 84:405. 

6. Feigin VL, Rinkel GJ, Algra A, et al. Calcium antagonists in patients with aneurysmal subarachnoid hemorrhage: a systematic review. Neurology 1998; 50:876.

7. Dorhout Mees SM, Rinkel GJ, Feigin VL, et al. Calcium antagonists for aneurysmal subarachnoid haemorrhage. Cochrane Database Syst Rev 2007; :CD000277.