Nimodipine prophylaxis in aneurysmal subarachnoid hemorrhage, a question of tradition or evidence: A scoping review

Background The prophylactic use of nimodipine following subarachnoid hemorrhage is a practice established four decades ago when clinical management differed from current and the concept of Delayed Cerebral Ischemia (DCI) was not established. The applicability of the original studies is limited by the fact of not reflecting current practice; by utilising a dichotomised outcome measure such as good neurological outcome versus death and vegetative state; by applying variable dosing regimens and including all causes of poor neurological outcome different than DCI. This study aims to review the available evidence to discuss the ongoing role of nimodipine in contemporaneous clinical practice. Methods PRISMA guidelines based review, evaluated the evidence on the prophylactic use of nimodipine. The following search engines: Medline, Embase, Cochrane, Web of Science and PubMed, identified Randomized Control Trials (RCTs) with neurological benefit as outcome measure and the impact of fixed versus weight-based nimodipine dosing regimens. Results Eight RCT were selected. Three of those trials with a total of 349 patients, showed a reduction on death and vegetative state (pooled RR: 0.62; 95 % confidence interval-CI: 0.45, 0.86) related to DCI. Amongst all studies, all cause death (pooled RR = 0.73, [95 % CI: 0.56, 0.97]) favoured a fixed-dose regimen (pooled RR: 0.60; [95 % CI: 0.43, 0.85]). Conclusion Available evidence demonstrates that nimodipine only reduces the risk for DCI-related death or vegetative state and that fixed-dose regimens favour all cause infarct and death independent of DCI. Contemporaneous studies assessing the benefit of nimodipine beyond death or vegetative states and applying individualized dosing are warranted.