Assessing the Time-Course of Dexmedetomidine-Induced Analgesia Via EEG

Mapping the Temporal Profile of Dexmedetomidine-Induced Analgesia Via EEG Signatures in Brain

Objective: To investigate the temporal dynamics of dexmedetomidine's analgesic effects in the brain using EEG.

Methods: Eligible patients scheduled for total hip arthroplasty under intrathecal anesthesia received a continuous infusion of DEX at 1.5 μg/(kg·h) for 15 minutes before neuraxial puncture, followed by an additional 15-minute infusion. The study was divided into three phases:

Phase 1: Non-dosing phase (Baseline). Phase 2: DEX preemptive analgesia phase (DEX infusion). Phase 3: DEX cessation phase (Post-infusion).

Outcomes:

Primary safety outcome: EEG spectral analysis at different phases. Secondary outcomes: NRS scores, postoperative nausea and vomiting (PONV), dizziness, agitation, and time to intestinal exhaust within 48 hours. Intraoperative hemodynamics were also monitored.

Objective: To investigate the temporal dynamics of dexmedetomidine's analgesic effects in the brain using EEG.

Methods: Eligible patients scheduled for total hip arthroplasty under intrathecal anesthesia received a continuous infusion of DEX at 1.5 μg/(kg·h) for 15 minutes before neuraxial puncture, followed by an additional 15-minute infusion. The study was divided into three phases:

Phase 1: Non-dosing phase (Baseline). Phase 2: DEX preemptive analgesia phase (DEX infusion). Phase 3: DEX cessation phase (Post-infusion).

Outcomes:

Primary safety outcome: EEG spectral analysis at different phases. Secondary outcomes: NRS scores, postoperative nausea and vomiting (PONV), dizziness, agitation, and time to intestinal exhaust within 48 hours. Intraoperative hemodynamic monitoring was performed.

EEG/ERP monitoring: The 64-site EEG and ERP were recorded at different phases

Inclusion Criteria:

Patients with hip osteoarthritis scheduled for total hip arthroplasty under intrathecal anesthesia; Age 18-70 years; American Society of Anesthesiologists (ASA) physical status classification I-III; Body mass index (BMI) 22-30 kg/m².

Exclusion Criteria:

Pre-existing peripheral or central nervous system disorders; Mental disorders; Cognitive impairment; Emergency surgery; or Hearing impairment.