Comparison of dexmedetomidine versus esmolol (Intravenously) in reduction of cardiovascular responses to intubation during induction of general anesthesia- A randomised clinical trial

Introduction and Aim: The cardiovascular changes to airway manipulation like tachycardia and hypertension occur secondary to catecholamine secretion. These changes make less effects on normal patients but can be hazardous in cardiac compromised patients. Various pharmacological measures are tried to lessen these ill effects. As a result we made an effort to compare the usefulness of two drugs, highly specific α2 agonist Dexmedetomidine at a dosage of 1µg/kg versus Esmolol 1mg/kg; in reducing these effects during induction of G.A. Materials and Methods: In this randomized clinical trial 102 patients, of age group 18-65 years and American Society of Anesthesiology classification I/ II, undergoing various surgeries under G.A. requiring intubation were distributed into 2 groups of 51 patients each. Group D patients were given Dexmeditomedine1µg/kg in diluted form over a time period of 10 minutes and Group E patients were given Esmolol 1mg/kg diluted to 10 ml and given over 1 min .Induction of anesthesia was done with volatile agent sevoflurane. Maintenance was done with O2 and N2O 30:60 along with vecuronium. Monitoring was done and hemodynamic parameters were recorded at particular intervals during laryngoscopy and intubation of trachea. Results: All observations were expressed as mean and standard deviation. Based on statistical analysis the Baseline heart rate, and baseline mean arterial pressure were comparable in both the groups. The decrease in mean HR observed at, 3, 5 and 10minutes after intubation in Group D was statistically highly significant compared to mean HR in group E (p<0.000).(table 2). The mean fall in SBP in group D at 1, 3, 5 and 10 minutes after intubation was statistically highly significant (p=0.000) compared to the Esmolol group E The fall in mean DBP value at 1,3, 5 and 10 minutes of intubation were statistically highly significant (p=0.000)in group D compared to the latter group. The mean basal MAP, 2min after drug administration and 1min after induction are comparable in both groups (p>0.05).The fall in mean MAP values in group D at 1, 3, 5 and 10 minutes of intubation were statistically highly significant (p<0.0000001) compared to group E. 1min after induction fall in mean RPP value in D group is statistically higher than in E Group (P=0.0243). We also noticed hypotension in 5 patients and a fall in heart rate in 3 patients of study group in group D which did not need any medication. However no patients in the latter group had these side effects, we attribute this to the lesser dosage of esmolol used. Conclusion: This study shows that dexmeditomedine 1µg/kg is better than esmolol 1mg/kg for lessening the stress response to airway manipulation.