Conscious Sedation with Dexmedetomidine or Midazolam during Endovascular Thrombectomy in Acute Ischemic Stroke: Protocol of the Multicenter PEACE Randomized Trial

Background: Dexmedetomidine (DEX) and midazolam (MDZ) are commonly used agents for conscious sedation in patients with acute ischemic stroke (AIS) treated with endovascular thrombectomy (EVT). While DEX offers superior sedation quality and potential neuroprotective effects, it is also associated with risk of hemodynamic instability. High-quality evidence directly comparing their impact on functional outcomes after EVT is lacking. This trial aims to determine whether conscious sedation with DEX, compared to MDZ, improves functional outcomes in patients with AIS due to anterior circulation large vessel occlusion (LVO) undergoing EVT. Methods: PEACE (Dexmedetomidine versus Midazolam for Conscious Sedation during Endovascular Stroke Thrombectomy) is a prospective, randomized, open label, blinded-endpoint, multicenter trial. Up to 810 patients with AIS due to LVO in the anterior circulation within 24 hours of last known well will be randomly assigned in a 1:1 ratio to receive either DEX or MDZ for conscious sedation during EVT across 30 centers in China. Results: The primary end point is the proportion of patients achieving a modified Rankin Scale (mRS) score 0-2 at 90 days, analyzed in the intention-to-treat population using a modified Poisson regression model, with results expressed as a risk ratio. Key secondary outcomes include the ordinal distribution of mRS scores at 90 days, and successful recanalization. Safety outcomes include symptomatic intracranial hemorrhage within 48 hours, and mortality at 90 days. Conclusion: The PEACE trial will provide definitive, high-level evidence on the comparative efficacy and safety of DEX versus MDZ for conscious sedation during EVT in patients with AIS due to LVO in the anterior circulation, with the goal of guiding clinical practice.