Effect of Dexmedetomidine Infusion on Hemodynamic Response During Laparoscopic Cholecystectomy

Abstract

Introduction: Laparoscopic cholecystectomy is a minimally invasive procedure associated with significant hemodynamic changes, primarily due to pneumoperitoneum. This stress response often elevates mean arterial pressure (MAP) and heart rate (HR), posing challenges for patients with cardiovascular conditions. Dexmedetomidine, an alpha-2 adrenergic agonist, has shown potential in stabilizing hemodynamics through its sedative, anxiolytic, and sympatholytic effects. This study aims to compare the efficacy of a dexmedetomidine loading dose followed by continuous infusion versus only a loading dose in maintaining hemodynamic stability during laparoscopic cholecystectomy.

Methodology: A prospective, randomized, double-blind study was conducted with 120 ASA Grade I and II patients undergoing laparoscopic cholecystectomy from October 2019 to March 2021. Participants were divided into two groups: Group D received a 1 µg/kg loading dose of dexmedetomidine followed by a continuous infusion of 0.2 µg/kg/hr, while Group NS received the same loading dose followed by a placebo. Hemodynamic parameters (HR and MAP) were monitored throughout the procedure. Postoperative pain and sedation were assessed using Visual Analogue Scale (VAS) and Ramsay Sedation Score (RSS).

Results: Group D showed significantly lower HR and MAP compared to Group NS, particularly after 40 and 60 minutes, respectively. Group D also demonstrated reduced postoperative analgesic requirements and better pain control. However, Group D had a higher incidence of bradycardia and hypotension, though no significant adverse effects like dry mouth were observed.

Conclusion: A dexmedetomidine regimen consisting of a 1 µg/kg loading dose followed by a continuous infusion of 0.2 µg/kg/hr is more effective in attenuating hemodynamic fluctuations and reducing postoperative analgesic needs compared to only a loading dose. This approach provides improved hemodynamic stability during laparoscopic cholecystectomy while maintaining acceptable sedation levels.