Magnesium Sulfate Therapy for Cerebral Vasospasm After Aneurysmal Subarachnoid Hemorrhage

Abstract

Object As magnesium is a potent cerebral vasodilator, we have investigated routine supplementation of magnesium (as a potent cerebral vasodilator) in patients presented with aneurysmal subarachnoid hemorrhage (ASAH) to determine whether there has been a reduction in the incidence of cerebral vasospasm. Materials and Methods A prospective randomized, placebo-controlled, clinical trial of high-dose magnesium sulfate (MgSO₄) therapy after ASAH was performed in 83 patients. MgSO₄ was administered intravenously as soon as possible after admission and continued until 10 days after occlusion of the aneurysm. Blood magnesium levels were obtained daily during MgSO₄ therapy. Outcome measures including the evidence of vasospasm on clinical examination using transcranial Doppler ultrasonographic recordings, or control angiogram within 10 days after occlusion of the aneurysm, were obtained. The clinical outcomes were recorded using Glasgow Outcome Scale (GOS) at 3 months. Results Eighty-three patients were enrolled in the study: 40 (12 male and 28 female patients) received MgSO₄ therapy and 43 (20 male and 23 female patients) comprised placebo-treated patients. The mean ages of the patients in these groups were 54 and 53 and the mean Fisher, Hunt and Hess grades were 3.02±0.97, 2.50±1.03 and 2.95±0.95, 2.32±0.96 in the treatment and control groups, respectively. The mean serum magnesium and calcium levels were 1.54±0.72, 8.24±0.94 and 0.88±0.13, 8.64±0.13 in the treatment and control groups, respectively. Ten out of 40 patients who received MgSO₄ therapy developed symptomatic vasospasm, confirmed by angiography and transcranial Doppler ultrasonography, compared with 14 of 43 patients among the control group (P=0.54). The mean GOS were 3.80±1.5 and 4.11±1.43 in the treatment and control groups, respectively P=0.78. Conclusions From our study, it appears that MgSO₄ therapy has no statistically significant beneficial role in the prevention of cerebral vasospasm after ASAH. We did observe, however, that the ultimate GOS was better in the treatment group than in the control group. To assess the safety and effectiveness of high-dosage MgSO₄ therapy or the adverse effects, large randomized, placebo-controlled, and double-blind clinical trials are needed.