Comparison of Intravenous Lignocaine and Dexmedetomidine in Attenuating the Haemodynamic Response to Laryngoscopy and Intubation: A Randomised Double-blind Clinical Study

Abstract

Introduction: Endotracheal intubation often triggers a sympathetic response, leading to an increase in Heart Rate (HR) and blood pressure. Dexmedetomidine (DEX) and lignocaine have shown the potential to mitigate cardiovascular changes secondary to intubation. Aim: To compare the efficacy of 0.25 mcg/kg and 0.5 mcg/kg DEX with 1.5 mg/kg lignocaine in attenuating haemodynamic responses during the peri-intubation period. Materials and Methods: This randomised double-blind study included 90 patients classified as American Society of Anaesthesiologists (ASA) I and II, aged 16-65 years. Patients were divided into three groups: Group A received lignocaine (1.5 mg/kg); Group B received DEX (0.25 mcg/kg); and Group C received DEX (0.5 mcg/kg). Haemodynamic parameters were recorded at various intervals before and after laryngoscopy. Data were checked for normality before statistical analysis using the Shapiro-Wilk test. Normally distributed continuous variables were compared using Analysis of Variance (ANOVA), while categorical variables were analysed using the Chi-square test. For all statistical tests, a p-value of less than 0.05 was considered indicative of a significant difference. Results: All groups were found to be comparable in terms of age, weight, and gender distribution. The mean age in Group A was 36.10±12.60 years, in Group B was 36.10±13.47 years, and in Group C was 37.37±11.49 years. Inter-group comparisons between Group A and Group C showed statistically significant lower HR values in Group C (79.23±10.37 vs. 90.7±17.68) at T0 as well as T1 (90.07±14.65 vs. 99.93±17.02, p-value 0.019). The comparison between Groups A and C revealed significantly lower Systolic Blood Pressure (SBP) values in Group C at T0, T1, T3, and T5. Inter-group comparisons between Groups A and B showed that Diastolic Blood Pressure (DBP) values were significantly lower at T5 in Group B (69.33±10.09 vs. 62.33±9.11, p-value 0.006). Between Groups A and C, significant differences were noted at T0, T1, T3, and T5 in Mean Arterial Pressure (MAP). Conclusion: DEX at a dose of 0.5 mcg/kg appears to be a more effective option for managing haemodynamic responses compared to lignocaine. Nevertheless, the haemodynamic stability achieved with 0.25 mcg/kg of DEX is nearly equivalent to that observed with both 0.5 mcg/kg of DEX and 1.5 mg/kg of lignocaine.

Keywords

• adrenergic alpha-2 receptor agonist
• airway management
• blood pressure
• general anaesthesia
• heart rate
• sympathetic nervous system