Comparison of dexmedetomidine and midazolam in reducing agitation in the ICU patients using the Richmond Agitation Sedation Scale (RASS) and Bispectral Index (BIS)

Abstract

Background & objective: Agitation is a frequent and serious complication in ICU patients undergoing mechanical ventilation (MV). It may be due to many causes, the most important being incomplete paralysis and inadequate sedation. Intensivists have used a variety of different options to prevent agitation. This study compared dexmedetomidine and midazolam in reducing agitation using the Richmond Agitation Sedation Scale (RASS) and Bispectral Index (BIS), and assessed sedation quality and hemodynamic effects.

Methods: A double-blind randomized clinical trial was conducted on 28 ICU patients who were on MV.  The patients were divided into two groups: either to receive an infusion of dexmedetomidine (0.4 µg/kg/hr) or midazolam (0.04 mg/kg/hr) following a standardized loading dose. RASS, BIS, and hemodynamic parameters were recorded at baseline, 4, 8, and 24 hours, and compared in two groups.

Results: At 8 and 24 hours, agitation occurred in 28.6% of midazolam patients versus 14.3% and 7.1% in the dexmedetomidine group (P < 0.05). BIS and RASS were strongly correlated (r > 0.8, P < 0.001). Dexmedetomidine significantly reduced heart rate and mean arterial pressure without adverse effects.

Conclusion: Dexmedetomidine is more effective than midazolam in reducing agitation, offering better sedation quality with stable hemodynamics. BIS complements RASS in guiding sedation in ICU settings.

Abbreviations: BIS: Bispectral Index, ICU: Intensive Care Unit, MAP: mean arterial pressure, RASS: Richmond Agitation Sedation Scale,

Keyword: Agitation; Bispectral Index; Dexmedetomidine; Intensive Care Units, Midazolam; Richmond Agitation Sedation Scale; Sedation

Citation: Adnani MI, Wijaya DW, Lubis B, Wahyuni AS. Comparison of dexmedetomidine and midazolam in reducing agitation in the ICU patients using the Richmond Agitation Sedation Scale (RASS) and Bispectral Index (BIS). Anaesth. pain intensive care 2025;29(7):743-748. DOI: 10.35975/apic.v29i7.2965

Received: May 22, 2025; Revised: June 09, 2025; Accepted: July 24, 2025