Primary objective: Experimental and clinical studies have suggested that magnesium has neuroprotective and vasodilatation properties. A meta-analysis was conducted to assess the effectiveness and safety of intravenous magnesium therapy in patients with aneurysmal subarachnoid haemorrhage (SAH).
Research design: Meta-analysis.
Methods and procedures: Medline, EMBASE and the Cochrane Library were searched for prospective controlled trials evaluating intravenous magnesium for treating SAH after a ruptured aneurysm without language restrictions. Two researchers performed the literature search and data extraction independently.
Main outcomes and results: Six prospective controlled trials involving 699 patients were included in this meta-analysis. Magnesium infusion reduced the risk of poor outcome and delayed cerebral ischemia (DCI): the relative risk was 0.62 (95% confidence interval (CI) 0.46-0.83) and 0.73 (95% CI 0.53-1.00), respectively. Sensitivity analyses were consistent with the meta-analysis. The withdrawal rate for adverse effects was higher in the magnesium-treatment arm compared to the placebo arm, RR 9.98 (95% CI 3.04-32.74).
Conclusion: The meta-analysis suggests that intravenous magnesium therapy reduces the risk of DCI and poor outcome after aneurysmal SAH. Serum magnesium should be routinely monitored for both effectiveness and safety considerations.