Comparison of Esmolol and Lignocaine in Attenuation of Stress Response to Laryngoscopy and Intubation – A Study in Kerala, South India

Context: Hypertension and tachycardia occurring during laryngoscopy and intubation could be deleterious to certain patients. Esmolol at doses of 100mg and 200mg have been studied extensively to attenuate the stress response to laryngoscopy and intubation. But this may produce undue bradycardia and hypotension. Using Esmolol at a lower dose of 1 mg/kg to attenuate the stress response will decrease its side effects.

Aims: To compare Esmolol at a low dose of 1 mg/kg  and Lignocaine 1.5 mg/kg in attenuation of the stress response to laryngoscopy and intubation

Settings and Design: The study was a randomized, parallel group, active controlled trial  conducted at SGMCRF.

Methods and Material: 60 healthy patients requiring  general anesthesia were randomly allocated to two groups of 30 each. Group L received  intravenous Lignocaine without preservative   1.5 mg/kg  and Group E received intravenous  Esmolol 1.0 mg/kg  3 minutes prior to laryngoscopy and intubation. Patients were premedicated with intravenous Midazolam 1 mg , induced with 2 mg/kg of intravenous Propofol and intubation facilitated by  intravenous Vecuronium 0.1 mg/kg . No surgical stimulation, analgesics or inhalational agents were allowed till 5 minutes after intubation and haemodynamic parameters were noted. There were no arrhythmias. The results were statistically analyzed.

Statistical analysis used: Statistical analysis was done by Student’s t test for quantitative data and Chi Square test and Fischer’s exact test  for qualitative  data. 

Results: Compared with the Lignocaine group, the attenuation of the stress response variables was better in the Esmolol group. The difference in the mean  Heart Rate ,Systolic Blood Pressure, Diastolic Blood Pressure and Mean Arterial Pressure between the two groups was significant statistically (P<0.05) at all time points  from the time of laryngoscopy and intubation till 5 min after laryngoscopy.

Conclusions: Esmolol at a low dose of 1 mg/kg was found to be  more effective than Lignocaine 1.5 mg/kg in controlling the stress response to laryngoscopy and intubation. Esmolol 1 mg/kg was found to be safe and effective in controlling the pressor response to laryngoscopy and intubation.