Effect of intravenous magnesium sulphate on hemodynamic response to pneumoperitoneum in laparoscopic cholecystectomy: A prospective, double blind study

Abstract

Background and Aim: Pneumoperitoneum (PP) for laparoscopic surgery is known to induce a pressor response. It can be attenuated by drugs, like opioids, vasodilators, beta blocking agents and alpha-2 agonists, but these drugs have their side effects. This study investigated the efficacy of magnesium sulphate to attenuate hemodynamic response associated with pneumoperitoneum in patients undergoing laparoscopic cholecystectomy. Methodology: This randomized, double blind, prospective study was carried out at Department of Anesthesiology, Maharishi Markandeshwar University, Mullana, Haryana (India). A total of 60 patients of ASA grade I or II, aged 20-60 y, of either sex, undergoing laparoscopic cholecystectomy, were randomly allocated into one of the two groups of 30 each. Standardized general anesthesia was administered to all patients. Group 1 patients received magnesium sulphate (30 mg/kg) intravenously as a bolus before induction of PP and Group 2 patients received same volume of 0.9% normal saline. Hemodynamic variables, e.g. heart rate (HR), systolic (SBP), diastolic (DBP), mean arterial pressures (MAP) were recorded from the start of surgery till extubation. Statistical analysis: SPSS version 17.0 for windows was used and p value of < 0.05 was considered significant. Results: Mean HR was 81.50 ± 8.44 vs. 93.03 ± 6.93/min, SBP was 126.37 ± 13.03 vs. 150.20 ± 10.45 mmHg, DBP was 82.50 ± 11.20 vs. 94.73 ± 8.33 mmHg, and MAP 98.43 ± 10.29 vs.113.27 ± 9.16 mmHg in Group 1 and Group 2, respectively, at 10 min after PP. Statistically significant fall in HR, SBP, DBP, MAP was seen in Group 1 at 10 min after PP till extubation. (p < 0.05). Conclusion: Intravenous magnesium sulphate effectively attenuates the hemodynamic response to pneumoperitoneum in laparoscopic cholecystectomy under general anesthesia.