Intravenous magnesium sulphate for aneurysmal subarachnoid hemorrhage: an updated systemic review and meta-analysis

INTRODUCTION: Previous meta-analyses of magnesium sulphate infusion in the treatment of aneurysmal subarachnoid hemorrhage (SAH) have become outdated due to recently published clinical trials. Our aim was thus to perform an up-to-date systemic review and meta-analysis of published data on the use of magnesium sulphate infusion in aneurysmal SAH patients. METHODS: A systemic review and meta-analysis of the literature was carried out on published randomized controlled clinical trials that investigated the efficacy of magnesium sulphate infusion in aneurysmal SAH patients. The results were analyzed with regard to delayed cerebral ischemia (DCI), delayed cerebral infarction, and favorable neurological outcomes at three and six months. The risks of bias were assessed using the Jadad criteria, with a Jadad score >3 indicating a lower such risk. Meta-analyses are presented in terms of relative risk (RR) with 95% confidence intervals (CIs). RESULTS: Six eligible studies with 875 patients were reviewed. The pooled RR for DCI was 0.87 (95% CI, 0.36 to 2.09; P = 0.75). That for delayed cerebral infarction was 0.58 (95% CI, 0.35 to 0.97; P = 0.04), although this result did not persist if only randomized clinical trials with a lower risk of bias were included (RR 0.61, 95% CI, 0.31 to 1.22; P = 0.17). The pooled RR for a favorable outcome at three months was 1.14 (95% CI, 0.99 to 1.31; P = 0.07), and that for a favorable outcome at six months was 1.08 (95% CI, 0.94 to 1.24; P = 0.29). CONCLUSIONS: The present findings do not lend support to a beneficial effect of magnesium sulphate infusion on delayed cerebral infarction. The reduction in DCI and improvement in the clinical outcomes of aneurysmal SAH patients following magnesium sulphate infusion observed in previous pilot studies are not confirmed, although a beneficial effect cannot be ruled out because of sample size limitation.