Intraoperative magnesium administration does not improve neurocognitive function after cardiac surgery.


Journal Article

Neurocognitive decline occurs frequently after cardiac surgery and persists in a significant number of patients. Magnesium is thought to provide neuroprotection by preservation of cellular energy metabolism, blockade of the N-methyl-D-aspartate receptor, diminution of the inflammatory response, and inhibition of platelet activation. We therefore hypothesized that intraoperative magnesium administration would decrease postoperative cognitive impairment.After approval by the Duke University Health System Institutional Review Board, 389 patients undergoing cardiac surgery were enrolled in this prospective, randomized, double-blind, placebo-controlled clinical trial. Subjects were randomized to receive magnesium as a 50 mg/kg bolus followed by another 50 mg/kg infusion for 3 hours or placebo bolus and infusion. Cognitive function was assessed preoperatively and again at 6 weeks postoperatively using a standardized test battery. Mean CD11b fluorescence and percentage of platelets expressing CD62P, which are markers of leukocyte and platelet activation, respectively, were assessed by flow cytometry as a secondary outcome. The effect of magnesium on postoperative cognition was tested using multivariable regression modeling, adjusting for age, years of education, baseline cognition, sex, race, and weight.Among the 389 allocated subjects (magnesium: n=198; placebo: n=191), the incidence of cognitive deficit in the magnesium group was 44.4% compared with 44.9% in the placebo group (P=0.93). The cognitive change score and platelet and leukocyte activation were also not different between the groups. Multivariable analysis revealed a marginal interaction between treatment group and weight such that heavier subjects receiving magnesium were less likely to have cognitive deficit (P=0.06).Magnesium administered intravenously during cardiac surgery does not reduce postoperative cognitive dysfunction. Unique identifier: NCT00041392.

Full Text

Duke Authors

Cited Authors

  • Mathew, JP; White, WD; Schinderle, DB; Podgoreanu, MV; Berger, M; Milano, CA; Laskowitz, DT; Stafford-Smith, M; Blumenthal, JA; Newman, MF; Neurologic Outcome Research Group (NORG) of The Duke Heart Center,

Published Date

  • December 2013

Published In

Volume / Issue

  • 44 / 12

Start / End Page

  • 3407 - 3413

PubMed ID

  • 24105697

Pubmed Central ID

  • 24105697

Electronic International Standard Serial Number (EISSN)

  • 1524-4628

International Standard Serial Number (ISSN)

  • 0039-2499

Digital Object Identifier (DOI)

  • 10.1161/STROKEAHA.113.002703


  • eng