gms | German Medical Science

Objective: Studies point out that magnesium acts as calcium antagonist and increases cerebral blood flow. Its use is well known in prevention of eclampsia-related convulsions and coronary spasm. In animal studies the outcome after cerebral ischemic lesion is better after treatment with magnesium phosphate. In the majority of patients with subarachnoid hemorrhage (SAH) hypomagnesaemia occurs. We have examined calcium and magnesium levels in 29 patients with SAH, and correlated them to neurological outcome at discharge.

Methods: Patients with subarachnoid hemorrhage treated on our intensive care units are given nimodipine per os (360mg/day and magnesium 300mg/day) after SAH due to cerebral aneurysm rupture. Serum and cerebrospinal fluid levels of calcium and magnesium were compared in 29 patients with SAH (15 patients without delayed neurological deficits versus 14 patients with neurological deficits). The average of the first and the last values of calcium and magnesium levels in serum and CSF were compared.

Results: The CSF calcium and magnesium values in patients with neurological deficits (n=14) at admission (1.25mmol/l vs. 1.11mmol/l) and at discharge (1.37mmol/l vs. 1.10mmol/l) were higher than in the population without neurological deficits. Serum calcium and magnesium levels were likewise higher in patients with neurological deficits at admission. At discharge serum Ca²⁺ was lower and Mg²⁺ was higher in comparison with the SAH population without deficits. However, the results did not reach statistical significance.

Conclusions: We observed a trend towards a correlation between clinical outcome and serum and CSF levels of Ca²⁺ and Mg²⁺. Magnesium sulphate concentrations and dosage in patients with subarachnoid hemorrhage are still unknown. Our data encourage to investigate a larger cohort group that would reach statistical significance.