“Comparative Evaluation of Effects of Single Dose Dexmedetomidine and Magnesium Sulphate On Hemodynamic Parameters during Laparoscopic Cholecystectomy under General Anesthesia”- A Randomized, Double blinded, Controlled Study

Background: Carbon dioxide pneumoperitoneum during laparoscopic surgery produces significant elevation of arterial pressure and systemic and pulmonary vascular resistance. Dexmedetomidine (DX) and magnesium sulfate (MG) both depress the sympathetic activity and control the hemodynamic responses to pneumoperitoneum. Bolus followed by continuous infusion of DX has been used during laparoscopic surgeries as per literature. In the present study, a single dose of DX was used in view of its elimination half-life (2.1–3.1 h) (duration of action up to 2 h), sufficient to cover the average period of pneumoperitoneum created for laparoscopic cholecystectomy (LC). Aim: The aim of this study was to compare the effects of a single dose of DX, MG, and normal saline (NS) on hemodynamic responses to pneumoperitoneum during LC and postoperative hemodynamic stability. Methods: Forty-five patients (the American Society of Anesthesiologists Class I, 18–60 years, male and female) undergoing elective LC were selected and randomly divided by computer-generated randomization table into three equal groups. Patients were given either 100 ml NS 0.9% intravenous (group NS, n = 15) or DX 1 μg/kg in 100 ml NS (group DX, n = 15) or MG 50 mg/kg in 100 ml NS (group MG, n = 15) over 10 min in double-blinded manner after induction of anesthesia but before the creation of pneumoperitoneum. All patients were monitored for their heart rate (HR), noninvasive blood pressure, oxygen saturation, end-tidal carbon dioxide (CO 2 ), intra-abdominal pressure, and isoflurane concentration and recorded at various intervals. Results: HR in groups DX and MG remained below the baseline value (before induction) of respective group throughout the procedure following the infusion of drug with a significant difference. There was also significant difference in HR among the groups at various time intervals ( P < 0.05). Systolic blood pressure was significantly different between groups NS and DX and groups DX and MG during the period of pneumoperitoneum at 10, 20, 30, and 40 min. A significant reduction in systolic blood pressure (SBP) of group DX as compared to its baseline value was observed throughout the period of pneumoperitoneum ( P < 0.05). Conclusion: D X 1 μg/kg and MG 50 mg/kg both were effective in their respective groups to control hemodynamic responses during CO 2 pneumoperitoneum created for LC. MG provided more stability in hemodynamic parameters, whereas DX was associated with more than desired reduction in HR and SBP, hence further evaluation with a lower dose of DX is suggested.