Magnesium sulfate versus dexmedetomidine as adjuvants for peribulbar block: a GRADE-assessed systematic review and meta-analysis

Regional anesthesia is widely used for ophthalmic surgery, but peribulbar block may have slower onset and variable akinesia. Dexmedetomidine and magnesium sulfate are used as adjuvants, yet their comparative effects remain uncertain.

This systematic review and meta-analysis followed PRISMA 2020 and Cochrane guidance (PROSPERO CRD420261435378). PubMed, Embase, Scopus, ScienceDirect, Cochrane and Google Scholar were searched from inception to May 2026 for randomized controlled trials comparing magnesium sulfate with dexmedetomidine as adjuvants to peribulbar local anesthetic. Random-effects meta-analysis used REML, conventional and Hartung-Knapp confidence intervals, prediction intervals, leave-one-out sensitivity analyses, dosage and surgery-based subgroup analyses, and GRADE assessment.