Magnesium Sulfate as a Multimodal Anesthetic Adjuvant in Brain Tumor Surgery: A Systematic Review and Meta-Analysis of Hemodynamic, Analgesic, and Biomarker Outcomes

Background/Objectives: Strict hemodynamic stability is critical during supratentorial craniotomy. This systematic review and meta-analysis aimed to evaluate the efficacy of magnesium sulfate (MgSO4) as a multimodal adjuvant on intraoperative hemodynamics, opioid consumption, and biomarker outcomes in this setting. Methods: We systematically searched PubMed, Scopus, EBSCO, and the Cochrane Library for randomized controlled trials (RCTs) comparing perioperative MgSO4 administration to placebo or standard care in adult patients undergoing elective supratentorial craniotomy. Results: Meta-analysis of nine included RCTs using a random-effects model demonstrated that MgSO4 significantly reduced intraoperative mean arterial pressure (mean difference [MD]: −4.65 mmHg; 95% confidence interval [CI]: −7.76 to −1.55; p = 0.0033; I2 = 73.6%). Furthermore, MgSO4 administration significantly lowered postoperative serum S100B levels (standardized MD [SMD]: −0.81; 95% CI: −1.24 to −0.38; p = 0.0002, I2 = 0.0%), indicating mitigated cellular neural damage, and decreased perioperative fentanyl consumption (standardized MD: −1.01; 95% CI: −1.45 to −0.57; p < 0.0001; I2 = 0.0%). Intraoperative blood loss volume did not differ significantly between groups (MD: −85.03 mL; 95% CI: −331.42 to 161.37; p = 0.4952; I2 = 92.5%). Conclusions: MgSO4 is a safe and effective multimodal adjuvant for supratentorial craniotomy, providing significant hemodynamic stability, opioid-sparing effects, and preliminary biochemical evidence suggestive of neuroprotection without compromising intraoperative hemostasis.