A Comparative Study to Assess the Efficacy of 2% Intravenous Lignocaine and 50% Magnesium Sulphate in Attenuating the Hemodynamic Response to Laryngoscopy

Abstract

Introduction: Hemodynamic response to laryngoscopy and intubation is a known phenomenon. Numerous pharmacological and non-pharmacological methods have been employed in an attempt to blunt such responses. However, the search for a perfect agent still continues. A study was conducted in order to compare and assess the efficacy of intravenous lignocaine and magnesium sulfate in blunting this hemodynamic response. Material And Methods: This prospective, double-blind, randomized, Helsinki protocol-compliant clinical study was conducted after written informed consent and approval from the Institutional Ethical Committee. Two groups of 40 subjects each were constituted. Group A received 2% lignocaine 1.5 mg/kg bolus given over 1-minute, while Group B received 50 % magnesium sulphate 30 mg/kg. Study drugs were administered over 10 minutes. Anaesthesia protocol was standardized. Hemodynamics were observed following study drug administration (5, 10 minutes), following induction and following induction and at intubation, and 1, 2, 4, 6, 8,10 minutes following laryngoscopy and intubation. Side effects were also noted. Results: Both groups were comparable demographically and at baseline, following the study drug administration. The difference between the two groups was clinically significant at 1, 2, 4, 6 minutes post-intubation (p = 0.005,0.001,0.004,0.006). The maximum observed heart rate in group B was immediately post-intubation, which was lower than the baseline. In terms of mean arterial pressure, significant intergroup difference was also observed immediately post-intubation and at 1, 2, 4, 6 and 8 minutes post-intubation (p = 0.04, 0.02, 0.02, 0.08). Conclusion: Intravenous magnesium sulphate 30 mg/kg ( group B) was more efficacious than lignocaine 1.5mg/kg ( group A ) in attenuating hemodynamic response to laryngoscopy and intubation.