Comparative Study of Dexmedetomidine and Propofol on Explicit Memory when used as Anaesthetic Intra-Operatively Under General Anaesthesia

Background: Awareness under general anesthesia, characterized by the explicit recall of intraoperative events, affects approximately 1-2 per 1,000 patients.Propofol, a commonly used intravenous anesthetic, is favored for its rapid onset and titratability, effectively reducing intraoperative awareness.Dexmedetomidine, a highly selective alpha-2 adrenergic agonist with sedative, anxiolytic, and opioid-sparing properties, offers minimal respiratory depression and is emerging as a potential anesthetic adjuvant.However, its role in suppressing explicit memory remains underexplored.Methods: This prospective, randomized, double-blinded study included 60 patients (ASA I-II), and was conducted in hospitals affiliated with Bangalore Medical College and Research Institute.Patients were randomly divided into two groups: Group A(Propofol): Bolus 1 mg/kg over 10 minutes, followed by infusion at 50mcg/kg/min.Group B(Dexmedetomidine): Bolus 1 mcg/kg over 10 minutes, followed by infusion at 0.5 mcg/kg/hr.General anesthesia techniques were standardized across both groups.Explicit memory was evaluated by Bispectral index score during surgery every 15 minutes with the target of 40-65.Sedation was assessed by the RAMSAY sedation scale in the immediate post-operative period.Recall of intra-operative events assessed by BRICE Questionnaire.Results: Both agents significantly reduced intraoperative awareness; however, dexmedetomidine demonstrated superior efficacy in suppressing explicit memory compared to propofol.Conclusion: Dexmedetomidine infusion at 0.5 mcg/kg/hr is more effective than propofol at 50 mcg/kg/min in reducing explicit intraoperative memory, supporting its potential as a valuable anesthetic adjunct.