title: The safety and feasibility of continuous intravenous magnesium sulfate for prevention of cerebral vasospasm in aneurysmal subarachnoid hemorrhage.
abstract: BACKGROUND
  Cerebral vasospasm in aneurysmal subarachnoid hemorrhage (SAH) is associated with poor outcome. The safety and feasibility of continuous high-dose intravenous magnesium sulfate (MgSO4) for the prevention of cerebral vasospasm and ischemic cerebral injury has not been well studied.
  
  
  METHODS
  Patients presenting to our center within 72 hours of aneurysmalSAH (confirmed by computed tomography [CT] scanning and cerebral angiography) between June 2001 and October 2002 were enrolled in a prospective pilot study in which they received MgSO4 as an adjunct to standard SAH management. Study patients received an intravenous infusion of 12 g of MgSO4 in a 500-mL solution of 0.9% NaCl administered at a rate of 4.06 mM (or 0.5 g) every hour over a 24-hour period for 10 days to achieve a target predetermined serum Mg range of more than 1.5 to less than 4.0 mM/L. The effect of MgSO4 on clinical examination, heart rate, and blood pressure was measured every 2 hours; serum glucose and phenytoin levels were monitored daily. Outcome measures included evidence of vasospasm on clinical examination, transcranial Doppler study ((TCD); velocity >or=100 cm/s), or repeat cerebral angiogram obtained within 10 days of SAH; and Glasgow Outcome Scale (GOS) score assessment and CT scan evidence of ischemic infarction at 30 days.
  
  
  RESULTS
  Nineteen patients (mean age: 55 years; range: 39-84 years; 11 males, 8 females) were enrolled in the study. Presenting Hunt Hess grade was II or higher; mean Fisher grade was 3. Vasospasm was observed in nine patients (by clinical examination in two, TCD in five, and angiogram in nine). The mean serum Mg level was 2.7 mM/L (standard deviation: +/- 0.37) and was maintained during the infusion period. No clinical adverse effects, hemodynamic changes, or fluctuations in serum glucose or phenytoin levels were observed. None of the patients died; no CT evidence of ischemic infarction was present; and most had good outcomes (GOS 5 in 10 patients; GOS 4 in 8 patients).
  
  
  CONCLUSIONS
  Our study confirmed the safety and feasibility of a continuous infusion of high-dose intravenous MgSO4 in patients with aneurysmal SAH. Randomized controlled trials are required to confirm the promising results.
authors.affiliation: Department of Neurology, Michigan State University, East Lansing, MI 48824, USA. yahia25@hotmail.com
authors.forename: Abutaher M
authors.initials: AM
authors.lastname: Yahia
authors.forename: Jawad F
authors.initials: JF
authors.lastname: Kirmani
authors.forename: Adnan I
authors.initials: AI
authors.lastname: Qureshi
authors.forename: Lee R
authors.initials: LR
authors.lastname: Guterman
authors.forename: L Nelson
authors.initials: LN
authors.lastname: Hopkins
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007262:Infusions, Intravenous; D008278:Magnesium Sulfate / Q000008:administration & dosage / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D010865:Pilot Projects; D013345:Subarachnoid Hemorrhage / Q000150:complications / Q000000981:diagnostic imaging / Q000628:therapy*; D016896:Treatment Outcome; D017585:Ultrasonography, Doppler, Transcranial; D020301:Vasospasm, Intracranial / Q000000981:diagnostic imaging / Q000517:prevention & control*
chemical_list: D008278:Magnesium Sulfate