Effect Of Single-Bolus Intravenous Dexmedetomidine Premedication on Perioperative Haemodynamic Response in Patients Undergoing Laparoscopic Cholecystectomy: A Randomized Double-Blind Placebo-Controlled Study

Abstract

Introduction: Laparoscopic cholecystectomy is routinely preferred for symptomatic gallbladder disease, yet carbon dioxide pneumoperitoneum, reverse Trendelenburg positioning, laryngoscopy and tracheal intubation can provoke clinically relevant tachycardia and pressor responses. Dexmedetomidine, through central alpha-2 adrenergic agonism, may blunt this sympathetic activation without meaningful respiratory depression. To evaluate whether a single intravenous bolus of dexmedetomidine given before intubation attenuates perioperative haemodynamic responses during elective laparoscopic cholecystectomy.

Materials and Methods: This prospective, randomized, double-blind, placebo-controlled comparative study included 60 ASA physical status I-II adults aged 20-55 years undergoing elective laparoscopic cholecystectomy. Group A received dexmedetomidine 1 mcg/kg diluted in 10 mL normal saline 15 minutes before intubation, while Group B received 10 mL normal saline. Pulse rate, systolic blood pressure, diastolic blood pressure, mean arterial pressure, SpO2 and EtCO2 were recorded at baseline, after intubation and during pneumoperitoneum.

Results: Group A showed consistently lower pulse rate and blood pressure readings across the critical perioperative intervals. At 15 minutes of pneumoperitoneum, pulse rate was 70.83 ± 12.02 beats/min in Group A compared with 100.74 ± 6.08 beats/min in Group B (p=0.008). At 30 minutes, systolic blood pressure was 112.34 ± 10.75 mmHg versus 138.59 ± 7.25 mmHg (p=0.003), and diastolic blood pressure was 69.27 ± 7.63 mmHg versus 82.89 ± 7.07 mmHg (p=0.007). Mean arterial pressure at 75 minutes was 83.88 ± 6.63 mmHg in Group A and 102.76 ± 5.88 mmHg in Group B (p=0.004). SpO2 and EtCO2 showed statistically significant but clinically small between-group differences, with both parameters remaining within acceptable intraoperative ranges.

Conclusion: A single pre-intubation intravenous bolus of dexmedetomidine 1 mcg/kg was associated with better attenuation of perioperative tachycardic and pressor responses during laparoscopic cholecystectomy, without clinically meaningful deterioration in oxygenation or ventilation.