Background and aims: Laryngoscopy and endotracheal intubation is often associated with hypertension and tachycardia because of sympatho-adrenal stimulation. Various methods/drugs have been tried to reduce this response. This study was undertaken to evaluate the effectiveness of oral clonidine to attenuate the haemodynamic response associated with powerful stimulus of laryngoscopy and endotracheal intubation and its effects were compared with intravenous lignocaine.

Methods: A prospective randomized clinical study was conducted on ninety patients, scheduled for various elective surgical procedures of 1 to 2 hours duration belonging to ASA class I and II .The patients were normotensive with age varying from 20 to 50 years of either gender. The patients were assigned into either of three groups as – Lignocaine (II) group (1.5mg/kg), clonidine (III) group (0.2mg orally) and control (I) group (patients not receiving any of the above drugs). The haemodynamic parameters (heart rate, systolic blood pressure, diastolic blood pressure, mean arterial pressure) were recorded at scheduled intervals. The data was analysed by applying chi square test (P>0.05) and Z test for comparison between the groups and paired‘t’ test for comparison within the group. Results: It was observed statistically that the hemodynamic parameters like heart rate, systolic blood pressure, diastolic blood pressure at 1, 2 ,3 minutes post laryngoscopy increased significantly in control group when compared to lignocaine and clonidine group . Whereas the rise in the hemodynamic parameters at the same intervals post layngoscropy was not statistically significant in clonidine group when compared to lignocaine group .Conclusion: Clonidine is a better drug for attenuation of cardiovascular responses

Key words: pressor response, Clonidine, lignocaine