Comparison of effects of rocuronium bromide versus vecuronium bromide on hemodynamic parameters during anaesthesia for elective surgical procedures

Background: Understanding haemodynamic effects of muscle relaxants may help us in selection of most appropriate muscle relaxant in a given case after considering preoperative cardiac status, preoperative medications, anaesthetic drugs to be used, nature of surgery and desirable intraoperative hemodynamics. Hemodynamic effects of rocuronium are not as clear as vecuronium. Present study was conducted to compare haemodynamic parameters during general anaesthesia for elective surgical procedures with vecuronium vs. rocuronium as muscle relaxant.Methods: Haemodynamic effects of vecuronium 0.15 mg/kg and 0.9 mg/kg of rocuronium was evaluated in patients (25 patients in each group) undergoing elective surgical procedures not lasting more than two hours. During this study period patients were evaluated for heart rate (HR), systolic BP (SBP), diastolic BP (DBP) and mean arterial pressure (MAP).Results: When both groups were compared, degree of fall in heart rate was more in vecuronium group (V group) compared to rocuronium group at all-time intervals after administration of drug. The fall in mean heart rate in V group was significant at two minutes after administration of muscle relaxant when compared to R group i.e.77.12±9.96 vs. 85.04±12.82 (p<0.05) and was highly significant at 3 minutes after administration of drug i.e. 76.12±9.67 vs. 85.44±12.47 (p<0.001). After induction and administration of vecuronium or rocuronium there was fall in systolic blood pressure, diastolic blood pressure and mean arterial pressure in both the groups when these parameters were recorded before laryngoscopy with slightly more but comparatively non-significant fall in these parameters in vecuronium group. Intraoperatively these parameters were comparable in both groups and no significant difference from baseline was observed in these parameters in both groups thereby showing good haemodynamic stability.Conclusions: Vecuronium is associated with greater decrease in heart rate than rocuronium in clinical doses. No increase in heart rate was observed with rocuronium in doses used. In all other aspects (SBP, DBP, MAP) haemodynamic effects were similar in both groups with slightly greater but non-significant fall observed after administration of vecuronium group.