Takeuchi S, Kumagai K, Toyooka T, et al. - With patients who have poor-grade subarachnoid hemorrhage, researchers conducted this randomized controlled clinical trial to assess intracisternal magnesium sulfate infusion combined with intravenous hydrogen therapy. For this analysis, 37 patients with poor-grade subarachnoid hemorrhage were randomly allocated to Mg+H₂, Mg, and control groups. Mg and Mg+H₂ groups obtained intracisternal magnesium sulfate infusion (2.5 mmol/L) at 20 mL/h for 14 days. In the Mg+H₂ group, serum neuron-specific enolase levels from days 3 to 14 were significantly lower vs the control group. If started immediately following surgery, intracisternal magnesium sulfate infusion decreases the occurrence of cerebral vasospasm and delays cerebral ischemia and improves clinical outcomes with no complications in patients with poor subarachnoid hemorrhage grades. Combined with intravenous hydrogen treatment, intracisternal magnesium sulfate infusion lowers serum malondialdehyde and neuron-specific enolase and improves the Barthel index, suggesting that hydrogen has additional effects.